Dicyclomine is an antimuscarinic, anticholinergic medication. It is used as an antispasmodic agent in the treatment of functional gastrointestinal (GI) bowel conditions and irritable bowel syndrome (IBS) not associated with constipation. Dicyclomine has been used medically for many decades, and it remains one of the more frequently prescribed GI agents among many marketed antimuscarinic agents. Safety and efficacy have not been established in pediatric patients, though the drug has been used in children and adolescents for functional GI disorders. Dicyclomine should not be used in infants less than 6 months of age; severe adverse effects have occurred in very young infants when dicyclomine was used to treat symptoms of infant colic. Despite decades of use, there continues to be a relative lack of high-quality data to support the use of antimuscarinic agents for IBS and functional GI bowel conditions in adults. Thus, guidelines generally do not recommend use of antispasmodics to treat global IBS symptoms. Safety and efficacy data for pediatric patients are not available. Side effects are common, particularly in older adults, even though some patients report symptomatic relief with use of these agents. Dicyclomine was initially FDA approved in 1951.
General Administration Information
For storage information, see the specific product information within the How Supplied section.
Route-Specific Administration
Oral Administration
-May be administered without regard to meals.
Oral Liquid Formulations
Oral solutions or syrups:
-Measure dosage with a calibrated oral measuring device to ensure accurate dosing.
-For administration to infants and children 6 months to less than 2 years of age, it has been suggested to dilute the syrup with an equal volume of water, and then administer doses 15 minutes before feeding.
Injectable Administration
-For intramuscular administration only. Do not administer by any other route.
-Visually inspect parenteral products for particulate matter and discoloration prior to administration whenever solution and container permit.
Intramuscular Administration
-Inject into a large muscle mass. Aspirate the syringe before injecting to avoid intravascular injection, since thrombosis may occur if the drug is inadvertently injected intravascularly.
-Intended to be used only for 1 or 2 days when the patient cannot take oral medication. Replace with oral therapy as soon as possible.
Adverse reactions seen with use of dicyclomine are related to its inhibitory action at muscarinic receptors. They are dose-dependent, and are usually reversible with discontinuation of therapy. In clinical trials 61% of patients reported experiencing adverse reactions to dicyclomine, and 9% of patients discontinued use due to at least 1 of these adverse reactions. At initial doses of 160 mg/day 33% of these patients reported xerostomia (dry mouth), 40% reported dizziness, 27% reported blurred vision, 14% reported nausea, 9% reported drowsiness, 7% reported asthenia, and 6% reported nervousness.
Gastrointestinal adverse effects reported with postmarketing use of dicyclomine include abdominal distention (bloating), abdominal pain, constipation, dyspepsia, xerostomia, ageusia (taste loss), anorexia, nausea, and vomiting.
Dermatologic and allergic-type adverse effects reported with the use of dicyclomine include drug hypersensitivity, facial edema, angioedema, rash, and anaphylactic shock. Urticaria and itching (pruritus) have been reported with drugs that have similar anticholinergic and antispasmodic actions.
Nervous system adverse effects reported with dicyclomine use include dizziness, light-headedness, headache, drowsiness, weakness, paresthesias, confusion and/or excitement (especially in geriatric adults), dyskinesia, lethargy, insomnia, speech disturbance, hallucinations, syncope, fatigue, malaise, delirium, amnesia, agitation, delusion, disorientation, mania, altered mood, and pseudodementia.
Cardiovascular adverse effects reported with the use of dicyclomine include palpitations and tachyarrhythmias. Hypertension has been reported with drugs that have similar anticholinergic and antispasmodic actions.
Respiratory system adverse effects reported with the use of dicyclomine include dyspnea, asphyxia, and nasal congestion. Sneezing and apnea have been reported with drugs that have similar anticholinergic and antispasmodic actions. Use of dicyclomine in young infants has resulted in serious respiratory symptoms (dyspnea, shortness of breath, breathlessness, respiratory collapse, apnea and asphyxia), along with seizures, syncope, pulse rate fluctuations, muscular hypotonia, and coma, and death in some published case reports; however, no causal relationship has been established. Do not use dicyclomine in infants less than 6 months of age due to these potential safety concerns.
Reproductive system adverse effects reported with the use of dicyclomine include lactation suppression. Impotence (erectile dysfunction) has been reported with drugs that have similar anticholinergic and antispasmodic actions.
Ocular adverse events reported postmarketing with the use of dicyclomine include blurred vision, mydriasis, and cycloplegia. Ocular side effects reported with drugs with similar anticholinergic or antispasmodic action include diplopia and increased ocular tension (ocular hypertension).
Adverse effects reported with anticholinergic or antispasmodic drugs that may potentially occur with dicyclomine use include urinary hesitancy and urinary retention in patients with prostatic hypertrophy or risk factors for urinary retention.
Dicyclomine solution for injection is intended for intramuscular administration, and an injection site reaction consisting of local skin irritation and focal coagulation may be seen. With inadvertent intravenous administration, thrombosis, thrombophlebitis, local pain, edema, changes in skin color, and reflex sympathetic dystrophy syndrome may occur.
Dicyclomine injection is for intramuscular administration only; do not give via intravenous administration. Inadvertent intravenous administration may result in thrombosis, thrombophlebitis, pain, and serious injection site reactions.
Dicyclomine is contraindicated in patients with unstable cardiovascular status in acute hemorrhagic shock. Use dicyclomine with caution in conditions characterized by tachyarrhythmia such as thyrotoxicosis, congestive heart failure and in cardiac surgery; dicyclomine may further accelerate the heart rate. Investigate any tachycardia before administration of dicyclomine. Care is required in patients with coronary artery disease, as ischemia and risk for infarction may be worsened, and in patients with hypertension. The peripheral effects of dicyclomine are a consequence of their inhibitory effect on muscarinic receptors of the autonomic nervous system and include potential for transient bradycardia followed by tachycardia, with palpitations and arrhythmias.
Dicyclomine is contraindicated in persons with GI obstruction or severe ulcerative colitis. Caution should be taken in patients with ulcerative colitis that is less severe. Large doses may suppress intestinal motility to the point of producing a paralytic ileus and the use of this drug may precipitate or aggravate the serious complication of toxic megacolon. The peripheral effects of dicyclomine are due to an inhibitory effect on muscarinic receptors of the autonomic nervous system and include a reduction in the tone and motility of the GI tract. Diarrhea may be an early symptom of incomplete intestinal obstruction, especially in patients with ileostomy or colostomy, and use in these patients would be inappropriate and could be harmful. A rare issue is the development of Ogilvie's syndrome (colonic pseudo-obstruction) which presents with signs, symptoms, and radiographic appearance of an acute large bowel obstruction but with no evidence of distal colonic obstruction. Toxic dilatation of the intestine and GI perforation is possible when anticholinergic agents are administered in patients with Salmonella dysentery.
Dicyclomine is contraindicated for use in persons with reflux esophagitis and should be used with caution in patients gastroesophageal reflux disease (GERD). Antimuscarinic agents decrease gastric motility and relax the lower esophageal sphincter. These effects promote gastric retention and aggravate reflux in these patients.
Dicyclomine is contraindicated in patients with urinary tract obstruction (obstructive uropathy). It should be used with caution in persons with known prostatic hypertrophy or other risks for urinary retention because the peripheral antimuscarinic effects of dicyclomine can cause difficulty with micturition and aggravate urinary retention.
Dicyclomine is contraindicated in patients with glaucoma. The peripheral effects of dicyclomine are a consequence of their inhibitory effect on muscarinic receptors of the autonomic nervous system and include dilatation of the pupils (mydriasis) with loss of accommodation (cycloplegia) and photophobia. Mydriasis may increase intraocular pressure.
Dicyclomine is contraindicated in patients with myasthenia gravis. With overdosage of dicyclomine, a curare-like action may occur (i.e., neuromuscular blockade leading to muscular weakness and possible paralysis). It should not be given to patients with myasthenia gravis except to reduce adverse muscarinic effects of an anticholinesterase. Because of the inhibitory effect of dicyclomine on muscarinic receptors within the autonomic nervous system, caution should be taken in patients with autonomic neuropathy.
Dicyclomine should be used with caution in hepatic disease or renal impairment as the effects of these conditions on the pharmacokinetics, safety or efficacy of dicyclomine have not been studied. Dicyclomine is known to be substantially excreted by the kidney, and the risk of toxic reactions to this drug may be greater in those with impaired renal function.
Dicyclomine can produce drowsiness, dizziness, or blurred vision. Individuals receiving this medication should be warned not to engage in activities requiring mental alertness, such as driving or operating machinery or performing hazardous work until they are aware of how the medication affects them. CNS effects may rarely include behavioral changes. Psychosis and delirium have been reported in sensitive individuals (such as the elderly and/or individuals with known mental illness) given anticholinergic drugs. These CNS signs and symptoms usually resolve within 12 to 24 hours after discontinuation of the drug.
The anticholinergic effects of dicyclomine may be significant and are additive with other anticholinergic medications. This is especially true for the older adult, but may also occur with any patient. Consider the anticholinergic burden of all applicable medication therapies and consider the potential for additive side effects. Caution persons treated with dicyclomine about ambient temperature increase. High environmental temperatures or fever may increase the risk of heat prostration (heat stroke) while taking anticholinergic medications. If symptoms occur, discontinue dicyclomine and institute supportive measures.
Clinical experience has not identified differences in responses between geriatric and younger adults receiving dicyclomine, but the dosage should be initiated at the lower end of the usual adult dosage range. Older patients are more susceptible to anticholinergic effects of dicyclomine, which can be significant and are additive with other anticholinergic medications. According to the Beers Criteria, antispasmodics such as dicyclomine are considered potentially inappropriate medications (PIMs) in geriatric adults; avoid due to uncertain effectiveness and the high anticholinergic activity. Avoid drugs with strong anticholinergic properties in those with the following conditions due to the potential for symptom exacerbation or adverse effects: dementia/cognitive impairment (adverse CNS effects), delirium/high risk of delirium (new-onset or worsening delirium), or lower urinary tract symptoms/benign prostatic hyperplasia in men (urinary retention or hesitancy).
No adequate and well controlled studies of dicyclomine have been conducted during pregnancy at recommended doses of 80 to 160 mg/day. Although there are no clinical trials, epidemiologic studies did not show an increased risk of structural malformations in babies born to pregnant individuals who took dicyclomine at doses up to 40 mg/day during the first trimester. Reproduction studies have been performed in rats and rabbits at doses up to 33 times the maximum recommended human dose based on 160 mg/day (3 mg/kg) and have revealed no evidence of harm to the fetus due to dicyclomine. Dicyclomine was used historically as part of a 3-medication combination product (dicyclomine; doxylamine; pyridoxine) to treat nausea and vomiting during pregnancy, but the products (e.g., Bendectin, Debendox) were withdrawn from the market due to litigation. However, expert analyses concluded that there was no difference in the risk of birth defects between those infants whose mothers had taken the combination products during the first trimester of pregnancy and those infants whose mothers had not.
Dicyclomine is contraindicated during breast-feeding. Dicyclomine is excreted into human milk. The use of dicyclomine in breast-feeding individuals is not recommended, due to potential serious adverse events that may occur from infant ingestion of the drug. Respiratory distress has been reported in infants aged less than 6 months who ingested dicyclomine directly (not via breast milk). In addition, anticholinergics such as dicyclomine may inhibit lactation.
While off-label use of dicyclomine is reported in pediatric patients, safety and efficacy in infants, children and adolescents have not been established. Dicyclomine is contraindicated in neonates and infants less than 6 months of age. Dicyclomine use in infants has been followed by serious respiratory symptoms (dyspnea, shortness of breath, breathlessness, respiratory collapse, apnea and asphyxia), seizures, syncope, pulse rate fluctuations, muscular hypotonia, and coma, and death, however; no causal relationship has been established.
For the treatment of irritable bowel syndrome and other functional disturbances of GI motility:
Oral dosage:
Adults: 20 mg PO 4 times daily, initially. If needed, may increase after the first week to 40 mg PO 4 times daily unless side effects limit dose escalation. Max: 160 mg/day; however, documented safety data are not available for doses above 80 mg/day for periods longer than 2 weeks. If efficacy is not achieved within 2 weeks of therapy, or if side effects develop which require doses less than 80 mg/day, consider drug discontinuation.
Adolescents*: Dosage not been established. 10 to 20 mg PO 3 to 4 times daily has been used. Suggested Max: 80 mg/day PO.
Children 2 to 12 years*: Dosage not established. 10 mg PO 3 to 4 times daily has been used. Do not exceed 40 mg/day.
Infants and Children 6 months to 1 year*: Dosage not been established. 5 to 10 mg PO 3 to 4 times daily, given 15 minutes before feeding, has been used. Do not exceed 40 mg/day.
Intramuscular dosage:
Adults: 10 to 20 mg IM 4 times daily. Only used for 1 or 2 days when the patient cannot take oral medication. Max: 80 mg/day.
Maximum Dosage Limits:
-Adults
160 mg/day PO or 80 mg/day IM; documented safety data are not available for total daily doses more than 80 mg/day PO for periods longer than 2 weeks.
-Geriatric
160 mg/day PO or 80 mg/day IM; documented safety data are not available for total daily doses more than 80 mg/day PO for periods longer than 2 weeks.
-Adolescents
80 mg/day PO has been suggested from off-label use.
-Children
2 to 12 years: 40 mg/day PO has been suggested from off-label use.
1 year: 40 mg/day PO has been suggested from off-label use.
-Infants
6 months and older: 40 mg/day PO has been suggested from off-label use.
Less than 6 months: Contraindicated.
-Neonates
Contraindicated.
Patients with Hepatic Impairment Dosing
Specific guidelines are not available. Use with caution in patients with hepatic disease.
Patients with Renal Impairment Dosing
Specific guidelines are not available. Use with caution in patients with renal disease.
*non-FDA-approved indication
AbobotulinumtoxinA: (Moderate) The use of systemic antimuscarinic/anticholinergic agents following the administration of botulinum toxins may result in a potentiation of systemic anticholinergic effects (e.g., blurred vision, dry mouth, constipation, or urinary retention).
Acetaminophen; Aspirin; Diphenhydramine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Acetaminophen; Caffeine; Dihydrocodeine: (Moderate) Monitor patients for signs of urinary retention or reduced gastric motility when dihydrocodeine is used concomitantly with an anticholinergic drug. The concomitant use of dihydrocodeine and anticholinergic drugs may increase risk of urinary retention and/or severe constipation, which may lead to paralytic ileus. Opiates increase the tone and decrease the propulsive contractions of the smooth muscle of the gastrointestinal tract. Prolongation of the gastrointestinal transit time may be the mechanism of the constipating effect.
Acetaminophen; Caffeine; Pyrilamine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Acetaminophen; Chlorpheniramine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Acetaminophen; Chlorpheniramine; Dextromethorphan: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Acetaminophen; Chlorpheniramine; Dextromethorphan; Phenylephrine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Acetaminophen; Chlorpheniramine; Dextromethorphan; Pseudoephedrine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Acetaminophen; Chlorpheniramine; Phenylephrine : (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Acetaminophen; Codeine: (Moderate) Monitor for signs of urinary retention or reduced gastric motility during concomitant codeine and dicyclomine use. Concomitant use may increase the risk of urinary retention and/or severe constipation, which may lead to paralytic ileus.
Acetaminophen; Dextromethorphan; Doxylamine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Acetaminophen; Diphenhydramine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Acetaminophen; Hydrocodone: (Moderate) Monitor for signs of urinary retention or reduced gastric motility during concomitant hydrocodone and dicyclomine use. Concomitant use may increase the risk of urinary retention and/or severe constipation, which may lead to paralytic ileus.
Acetaminophen; Oxycodone: (Moderate) Monitor for signs of urinary retention or reduced gastric motility during concomitant oxycodone and dicyclomine use. Concomitant use may increase the risk of urinary retention and/or severe constipation, which may lead to paralytic ileus.
Acetaminophen; Pamabrom; Pyrilamine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Acetylcholine Chloride: (Major) The muscarinic actions of drugs known as parasympathomimetics, including both direct cholinergic receptor agonists and cholinesterase inhibitors, can antagonize the antimuscarinic actions of anticholinergic drugs, and vice versa.
Aclidinium: (Moderate) Although aclidinium is minimally absorbed into the systemic circulation after inhalation, there is the potential for aclidinium to have additive anticholinergic effects when administered with other anticholinergics or antimuscarinics. Per the manufacturer, avoid concomitant administration of aclidinium with other anticholinergic medications, when possible.
Aclidinium; Formoterol: (Moderate) Although aclidinium is minimally absorbed into the systemic circulation after inhalation, there is the potential for aclidinium to have additive anticholinergic effects when administered with other anticholinergics or antimuscarinics. Per the manufacturer, avoid concomitant administration of aclidinium with other anticholinergic medications, when possible.
Acrivastine; Pseudoephedrine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Alfentanil: (Moderate) Monitor patients for signs of urinary retention or reduced gastric motility when alfentanil is used concomitantly with an anticholinergic drug. The concomitant use of alfentanil and anticholinergic drugs may increase risk of urinary retention and/or severe constipation, which may lead to paralytic ileus. Opiates increase the tone and decrease the propulsive contractions of the smooth muscle of the gastrointestinal tract. Prolongation of the gastrointestinal transit time may be the mechanism of the constipating effect.
Aliskiren; Hydrochlorothiazide, HCTZ: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Alosetron: (Major) Concomitant use of alosetron and anticholinergics, which can decrease GI motility, may seriously worsen constipation, leading to events such as GI obstuction, impaction, or paralytic ileus. Although specific recommendations are not available from the manufacturer, it would be prudent to avoid anticholinergics in patients taking alosetron.
Alprazolam: (Moderate) Dicyclomine can cause drowsiness, so it should be used cautiously in patients receiving CNS depressants like benzodiazepines.
Aluminum Hydroxide: (Moderate) Antacids may inhibit the oral absorption of anticholinergics. Simultaneous oral administration should be avoided when feasible; separate dosing by at least 2 hours to limit an interaction.
Aluminum Hydroxide; Magnesium Carbonate: (Moderate) Antacids may inhibit the oral absorption of anticholinergics. Simultaneous oral administration should be avoided when feasible; separate dosing by at least 2 hours to limit an interaction.
Aluminum Hydroxide; Magnesium Hydroxide: (Moderate) Antacids may inhibit the oral absorption of anticholinergics. Simultaneous oral administration should be avoided when feasible; separate dosing by at least 2 hours to limit an interaction.
Aluminum Hydroxide; Magnesium Hydroxide; Simethicone: (Moderate) Antacids may inhibit the oral absorption of anticholinergics. Simultaneous oral administration should be avoided when feasible; separate dosing by at least 2 hours to limit an interaction.
Aluminum Hydroxide; Magnesium Trisilicate: (Moderate) Antacids may inhibit the oral absorption of anticholinergics. Simultaneous oral administration should be avoided when feasible; separate dosing by at least 2 hours to limit an interaction.
Amantadine: (Moderate) Additive anticholinergic effects may be seen when dicyclomine is used concomitantly with other drugs that possess anticholinergic properties, such as amantadine. Clinicians should note that anticholinergic effects might be seen not only on GI smooth muscle, but also on bladder function, the eye, and temperature regulation. Additive drowsiness may also occur.
Amiloride; Hydrochlorothiazide, HCTZ: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Amitriptyline: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant tricyclic antidepressant and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Amlodipine; Valsartan; Hydrochlorothiazide, HCTZ: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Amobarbital: (Moderate) Dicyclomine can cause drowsiness, so it should be used cautiously in patients receiving CNS depressants like barbiturates.
Amoxapine: (Moderate) Depending on the specific agent, additive anticholinergic effects may be seen when amoxapine is used concomitantly with other anticholinergic agents. Clinicians should note that anticholinergic effects might be seen not only on GI smooth muscle, but also on bladder function, the eye, and temperature regulation. Additive CNS effects are also possible when these drugs are combined with amoxapine.
Antacids: (Moderate) Antacids may inhibit the oral absorption of anticholinergics. Simultaneous oral administration should be avoided when feasible; separate dosing by at least 2 hours to limit an interaction.
Antidiarrheals: (Moderate) Both antidiarrheals and anticholinergics, such as dicyclomine, decrease GI motility. Use of these drugs together may produce additive effects on the GI track; thereby increasing the risk for toxic megacolon.
Anxiolytics; Sedatives; and Hypnotics: (Moderate) Dicyclomine can cause drowsiness, so it should be used cautiously in patients receiving CNS depressants like anxiolytics, sedatives, and hypnotics.
Aspirin, ASA; Caffeine; Orphenadrine: (Moderate) Additive anticholinergic effects may be seen when dicyclomine is used concomitantly with other drugs that possess anticholinergic properties, such as orphenadrine. Clinicians should note that anticholinergic effects might be seen not only on GI smooth muscle, but also on bladder function, the eye, and temperature regulation. Additive drowsiness may also occur.
Aspirin, ASA; Carisoprodol; Codeine: (Moderate) Monitor for signs of urinary retention or reduced gastric motility during concomitant codeine and dicyclomine use. Concomitant use may increase the risk of urinary retention and/or severe constipation, which may lead to paralytic ileus.
Aspirin, ASA; Citric Acid; Sodium Bicarbonate: (Moderate) Separate the time of administration of oral dicyclomine and oral sodium bicarbonate by at least 2 hours. Simultaneous coadministration may decrease oral dicyclomine absorption and reduce efficacy.
Aspirin, ASA; Oxycodone: (Moderate) Monitor for signs of urinary retention or reduced gastric motility during concomitant oxycodone and dicyclomine use. Concomitant use may increase the risk of urinary retention and/or severe constipation, which may lead to paralytic ileus.
Atenolol; Chlorthalidone: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Azilsartan; Chlorthalidone: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Belladonna; Opium: (Moderate) Monitor patients for signs of urinary retention or reduced gastric motility when opium is used concomitantly with an anticholinergic drug. The concomitant use of opium and anticholinergic drugs may increase risk of urinary retention and/or severe constipation, which may lead to paralytic ileus. Opiates increase the tone and decrease the propulsive contractions of the smooth muscle of the gastrointestinal tract. Prolongation of the gastrointestinal transit time may be the mechanism of the constipating effect.
Benazepril; Hydrochlorothiazide, HCTZ: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Benzhydrocodone; Acetaminophen: (Moderate) Monitor patients for signs of urinary retention or reduced gastric motility when benzhydrocodone is used concomitantly with an anticholinergic drug. The concomitant use of benzhydrocodone and anticholinergic drugs may increase risk of urinary retention and/or severe constipation, which may lead to paralytic ileus. Opiates increase the tone and decrease the propulsive contractions of the smooth muscle of the gastrointestinal tract. Prolongation of the gastrointestinal transit time may be the mechanism of the constipating effect.
Benzodiazepines: (Moderate) Dicyclomine can cause drowsiness, so it should be used cautiously in patients receiving CNS depressants like benzodiazepines.
Bethanechol: (Major) The muscarinic actions of drugs known as parasympathomimetics, including both direct cholinergic receptor agonists and cholinesterase inhibitors, can antagonize the antimuscarinic actions of anticholinergic drugs, and vice versa.
Bismuth Subsalicylate: (Moderate) Both antidiarrheals and anticholinergics, such as dicyclomine, decrease GI motility. Use of these drugs together may produce additive effects on the GI track; thereby increasing the risk for toxic megacolon.
Bismuth Subsalicylate; Metronidazole; Tetracycline: (Moderate) Both antidiarrheals and anticholinergics, such as dicyclomine, decrease GI motility. Use of these drugs together may produce additive effects on the GI track; thereby increasing the risk for toxic megacolon.
Bisoprolol; Hydrochlorothiazide, HCTZ: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Botulinum Toxins: (Moderate) The use of systemic antimuscarinic/anticholinergic agents following the administration of botulinum toxins may result in a potentiation of systemic anticholinergic effects (e.g., blurred vision, dry mouth, constipation, or urinary retention).
Brompheniramine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Brompheniramine; Dextromethorphan; Phenylephrine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Brompheniramine; Phenylephrine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Brompheniramine; Pseudoephedrine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Brompheniramine; Pseudoephedrine; Dextromethorphan: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Buprenorphine: (Moderate) Monitor for signs of urinary retention or reduced gastric motility during concomitant buprenorphine and dicyclomine use. Concomitant use may increase the risk of urinary retention and/or severe constipation, which may lead to paralytic ileus.
Buprenorphine; Naloxone: (Moderate) Monitor for signs of urinary retention or reduced gastric motility during concomitant buprenorphine and dicyclomine use. Concomitant use may increase the risk of urinary retention and/or severe constipation, which may lead to paralytic ileus.
Bupropion: (Moderate) Additive anticholinergic effects may be seen when dicyclomine is used concomitantly with other drugs that possess anticholinergic properties, such as bupropion. Clinicians should note that anticholinergic effects might be seen not only on GI smooth muscle, but also on bladder function, the eye, and temperature regulation. Additive drowsiness may also occur.
Bupropion; Naltrexone: (Moderate) Additive anticholinergic effects may be seen when dicyclomine is used concomitantly with other drugs that possess anticholinergic properties, such as bupropion. Clinicians should note that anticholinergic effects might be seen not only on GI smooth muscle, but also on bladder function, the eye, and temperature regulation. Additive drowsiness may also occur.
Buspirone: (Moderate) Dicyclomine can cause drowsiness, so it should be used cautiously in patients receiving CNS depressants like buspirone.
Butalbital; Acetaminophen; Caffeine; Codeine: (Moderate) Monitor for signs of urinary retention or reduced gastric motility during concomitant codeine and dicyclomine use. Concomitant use may increase the risk of urinary retention and/or severe constipation, which may lead to paralytic ileus.
Butalbital; Aspirin; Caffeine; Codeine: (Moderate) Monitor for signs of urinary retention or reduced gastric motility during concomitant codeine and dicyclomine use. Concomitant use may increase the risk of urinary retention and/or severe constipation, which may lead to paralytic ileus.
Butorphanol: (Moderate) Monitor patients for signs of urinary retention or reduced gastric motility when butorphanol is used concomitantly with an anticholinergic drug. The concomitant use of butorphanol and anticholinergic drugs may increase risk of urinary retention and/or severe constipation, which may lead to paralytic ileus. Opiates increase the tone and decrease the propulsive contractions of the smooth muscle of the gastrointestinal tract. Prolongation of the gastrointestinal transit time may be the mechanism of the constipating effect.
Calcium Carbonate: (Major) Avoid concomitant use of calcium carbonate and anticholinergics. Antacids may interfere with the absorption of anticholinergics.
Calcium Carbonate; Famotidine; Magnesium Hydroxide: (Major) Avoid concomitant use of calcium carbonate and anticholinergics. Antacids may interfere with the absorption of anticholinergics.
Calcium Carbonate; Magnesium Hydroxide: (Major) Avoid concomitant use of calcium carbonate and anticholinergics. Antacids may interfere with the absorption of anticholinergics.
Calcium Carbonate; Magnesium Hydroxide; Simethicone: (Major) Avoid concomitant use of calcium carbonate and anticholinergics. Antacids may interfere with the absorption of anticholinergics.
Calcium Carbonate; Simethicone: (Major) Avoid concomitant use of calcium carbonate and anticholinergics. Antacids may interfere with the absorption of anticholinergics.
Calcium; Vitamin D: (Major) Avoid concomitant use of calcium carbonate and anticholinergics. Antacids may interfere with the absorption of anticholinergics.
Candesartan; Hydrochlorothiazide, HCTZ: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Captopril; Hydrochlorothiazide, HCTZ: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Carbidopa; Levodopa: (Minor) Anticholinergics can potentiate the dopaminergic effects of levodopa. While some patients may benefit from this interaction, clinicians should be ready to decrease doses of levodopa if an antimuscarinic is added.
Carbidopa; Levodopa; Entacapone: (Minor) Anticholinergics can potentiate the dopaminergic effects of levodopa. While some patients may benefit from this interaction, clinicians should be ready to decrease doses of levodopa if an antimuscarinic is added.
Carbinoxamine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Celecoxib; Tramadol: (Moderate) Monitor for signs of urinary retention or reduced gastric motility during concomitant tramadol and dicyclomine use. Concomitant use may increase the risk of urinary retention and/or severe constipation, which may lead to paralytic ileus.
Cetirizine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant cetirizine and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Cetirizine; Pseudoephedrine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant cetirizine and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Cevimeline: (Major) The muscarinic actions of drugs known as parasympathomimetics, including both direct cholinergic receptor agonists and cholinesterase inhibitors, can antagonize the antimuscarinic actions of anticholinergic drugs, and vice versa.
Chlophedianol; Dexbrompheniramine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Chlophedianol; Dexchlorpheniramine; Pseudoephedrine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Chlorcyclizine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Chlordiazepoxide: (Moderate) Dicyclomine can cause drowsiness, so it should be used cautiously in patients receiving CNS depressants like benzodiazepines.
Chlordiazepoxide; Amitriptyline: (Moderate) Dicyclomine can cause drowsiness, so it should be used cautiously in patients receiving CNS depressants like benzodiazepines. (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant tricyclic antidepressant and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Chlordiazepoxide; Clidinium: (Moderate) Dicyclomine can cause drowsiness, so it should be used cautiously in patients receiving CNS depressants like benzodiazepines.
Chlorothiazide: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Chlorpheniramine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Chlorpheniramine; Codeine: (Moderate) Monitor for signs of urinary retention or reduced gastric motility during concomitant codeine and dicyclomine use. Concomitant use may increase the risk of urinary retention and/or severe constipation, which may lead to paralytic ileus. (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Chlorpheniramine; Dextromethorphan: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Chlorpheniramine; Dextromethorphan; Phenylephrine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Chlorpheniramine; Dextromethorphan; Pseudoephedrine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Chlorpheniramine; Hydrocodone: (Moderate) Monitor for signs of urinary retention or reduced gastric motility during concomitant hydrocodone and dicyclomine use. Concomitant use may increase the risk of urinary retention and/or severe constipation, which may lead to paralytic ileus. (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Chlorpheniramine; Ibuprofen; Pseudoephedrine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Chlorpheniramine; Phenylephrine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Chlorpheniramine; Pseudoephedrine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Chlorpromazine: (Moderate) Additive anticholinergic effects may be seen when anticholinergics are used concomitantly with phenothiazines, including chlorpromazine. Clinicians should note that antimuscarinic effects may be seen not only on GI smooth muscle, but also on bladder function, the eye, and temperature regulation. Additive drowsiness or other additive CNS effects may also occur.
Chlorthalidone: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Cholinergic agonists: (Major) The muscarinic actions of drugs known as parasympathomimetics, including both direct cholinergic receptor agonists and cholinesterase inhibitors, can antagonize the antimuscarinic actions of anticholinergic drugs, and vice versa.
Cisapride: (Moderate) Avoid chronic administration of dicyclomine with prokinetic agents, such as cisapride, under most circumstances. Dicyclomine has antimuscarinic properties that may slow GI motility. The clinical significance of this interaction is uncertain.
Clemastine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Clomipramine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant tricyclic antidepressant and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Clonazepam: (Moderate) Dicyclomine can cause drowsiness, so it should be used cautiously in patients receiving CNS depressants like benzodiazepines.
Clorazepate: (Moderate) Dicyclomine can cause drowsiness, so it should be used cautiously in patients receiving CNS depressants like benzodiazepines.
Clozapine: (Major) Avoid co-prescribing clozapine with other anticholinergic medicines that can cause gastrointestinal hypomotility, due to a potential to increase serious constipation, ileus, and other potentially serious bowel conditions that may result in hospitalization. Clozapine exhibits potent anticholinergic effects. Additive anticholinergic effects may be seen when clozapine is used concomitantly with anticholinergic agents. Adverse effects may be seen not only on GI smooth muscle, but also on bladder function, the CNS, the eye, and temperature regulation. Additive drowsiness may also occur, depending on the anticholinergic agent used.
Codeine: (Moderate) Monitor for signs of urinary retention or reduced gastric motility during concomitant codeine and dicyclomine use. Concomitant use may increase the risk of urinary retention and/or severe constipation, which may lead to paralytic ileus.
Codeine; Guaifenesin: (Moderate) Monitor for signs of urinary retention or reduced gastric motility during concomitant codeine and dicyclomine use. Concomitant use may increase the risk of urinary retention and/or severe constipation, which may lead to paralytic ileus.
Codeine; Guaifenesin; Pseudoephedrine: (Moderate) Monitor for signs of urinary retention or reduced gastric motility during concomitant codeine and dicyclomine use. Concomitant use may increase the risk of urinary retention and/or severe constipation, which may lead to paralytic ileus.
Codeine; Phenylephrine; Promethazine: (Moderate) Monitor for signs of urinary retention or reduced gastric motility during concomitant codeine and dicyclomine use. Concomitant use may increase the risk of urinary retention and/or severe constipation, which may lead to paralytic ileus. (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant promethazine and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Codeine; Promethazine: (Moderate) Monitor for signs of urinary retention or reduced gastric motility during concomitant codeine and dicyclomine use. Concomitant use may increase the risk of urinary retention and/or severe constipation, which may lead to paralytic ileus. (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant promethazine and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Crofelemer: (Moderate) Pharmacodynamic interactions between crofelemer and antimuscarinics are theoretically possible. Crofelemer does not affect GI motility mechanisms, but does have antidiarrheal effects. Patients taking medications that decrease GI motility, such as antimuscarinics, may be at greater risk for serious complications from crofelemer, such as constipation with chronic use. Use caution and monitor GI symptoms during coadministration.
Cyclobenzaprine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant cyclobenzaprine and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Cyproheptadine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Dasiglucagon: (Major) The concomitant use of intravenous glucagon and anticholinergics increases the risk of gastrointestinal adverse reactions due to additive effects on inhibition of gastrointestinal motility. Concomitant use is not recommended.
DaxibotulinumtoxinA: (Moderate) The use of systemic antimuscarinic/anticholinergic agents following the administration of botulinum toxins may result in a potentiation of systemic anticholinergic effects (e.g., blurred vision, dry mouth, constipation, or urinary retention).
Desipramine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant tricyclic antidepressant and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Dexbrompheniramine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Dexbrompheniramine; Pseudoephedrine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Dexchlorpheniramine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Dexchlorpheniramine; Dextromethorphan; Pseudoephedrine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Dextromethorphan; Bupropion: (Moderate) Additive anticholinergic effects may be seen when dicyclomine is used concomitantly with other drugs that possess anticholinergic properties, such as bupropion. Clinicians should note that anticholinergic effects might be seen not only on GI smooth muscle, but also on bladder function, the eye, and temperature regulation. Additive drowsiness may also occur.
Dextromethorphan; Diphenhydramine; Phenylephrine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Dextromethorphan; Quinidine: (Moderate) Additive anticholinergic effects may be seen when dicyclomine is used concomitantly with other drugs that possess anticholinergic properties, such as quinidine. Clinicians should note that anticholinergic effects might be seen not only on GI smooth muscle, but also on bladder function, the eye, and temperature regulation. Additive drowsiness may also occur.
Diazepam: (Moderate) Dicyclomine can cause drowsiness, so it should be used cautiously in patients receiving CNS depressants like benzodiazepines.
Digoxin: (Moderate) Anticholinergics, because of their ability to cause tachycardia, can antagonize the beneficial actions of digoxin in atrial fibrillation/flutter. Routine therapeutic monitoring should be continued when an antimuscarinic agent is prescribed with digoxin until the effects of combined use are known.
Dimenhydrinate: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Diphenhydramine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Diphenhydramine; Ibuprofen: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Diphenhydramine; Naproxen: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Diphenhydramine; Phenylephrine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Disopyramide: (Moderate) In addition to its electrophysiologic effects, disopyramide exhibits clinically significant anticholinergic properties. These can be additive with other anticholinergics. Clinicians should be aware that urinary retention, particularly in males, and aggravation of glaucoma are realistic possibilities of using disopyramide with other anticholinergic agents.
Donepezil: (Moderate) The therapeutic benefits of donepezil, a cholinesterase inhibitor, may be diminished during chronic co-administration with antimuscarinics or medications with potent anticholinergic activity. When concurrent use is not avoidable, the patient should be monitored for cognitive decline and anticholinergic side effects. Clinicians should generally avoid multiple medications with anticholinergic activity in the patient with dementia. Some of the common selective antimuscarinic drugs for bladder problems, (such as oxybutynin, darifenacin, trospium, fesoterodine, tolerodine, or solifenacin), do not routinely cause problems with medications used for dementia, but may cause anticholinergic side effects in some patients. Atropine may be used to offset bradycardia in cholinesterase inhibitor overdose.
Donepezil; Memantine: (Moderate) The adverse effects of anticholinergics, such as dry mouth, urinary hesitancy or blurred vision may be enhanced with use of memantine; dosage adjustments of the anticholinergic drug may be required when memantine is coadministered. In addition, preliminary evidence indicates that chronic anticholinergic use in patients with Alzheimer's Disease may possibly have an adverse effect on cognitive function. Therefore, the effectiveness of drugs used in the treatment of Alzheimer's such as memantine, may be adversely affected by chronic antimuscarinic therapy. (Moderate) The therapeutic benefits of donepezil, a cholinesterase inhibitor, may be diminished during chronic co-administration with antimuscarinics or medications with potent anticholinergic activity. When concurrent use is not avoidable, the patient should be monitored for cognitive decline and anticholinergic side effects. Clinicians should generally avoid multiple medications with anticholinergic activity in the patient with dementia. Some of the common selective antimuscarinic drugs for bladder problems, (such as oxybutynin, darifenacin, trospium, fesoterodine, tolerodine, or solifenacin), do not routinely cause problems with medications used for dementia, but may cause anticholinergic side effects in some patients. Atropine may be used to offset bradycardia in cholinesterase inhibitor overdose.
Doxepin: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant tricyclic antidepressant and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Doxylamine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Doxylamine; Pyridoxine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Dronabinol: (Moderate) Use caution if coadministration of dronabinol with anticholinergics is necessary. Concurrent use of dronabinol, THC with anticholinergics may result in additive drowsiness, hypertension, tachycardia, and possibly cardiotoxicity.
Eluxadoline: (Major) Avoid use of eluxadoline with medications that may cause constipation, such as anticholinergics. Discontinue use of eluxadoline in patients who develop severe constipation lasting more than 4 days.
Enalapril; Hydrochlorothiazide, HCTZ: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Eprosartan; Hydrochlorothiazide, HCTZ: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Estazolam: (Moderate) Dicyclomine can cause drowsiness, so it should be used cautiously in patients receiving CNS depressants like benzodiazepines.
Eszopiclone: (Moderate) Dicyclomine can cause drowsiness, so it should be used cautiously in patients receiving CNS depressants like anxiolytics, sedatives, and hypnotics.
Fentanyl: (Moderate) Monitor for signs of urinary retention or reduced gastric motility during concomitant fentanyl and dicyclomine use. Concomitant use may increase the risk of urinary retention and/or severe constipation, which may lead to paralytic ileus.
Fluphenazine: (Moderate) Additive anticholinergic effects may be seen when anticholinergics are used concomitantly with phenothiazines, including fluphenazine. Clinicians should note that antimuscarinic effects may be seen not only on GI smooth muscle, but also on bladder function, the eye, and temperature regulation. Additive drowsiness or other additive CNS effects may also occur.
Flurazepam: (Moderate) Dicyclomine can cause drowsiness, so it should be used cautiously in patients receiving CNS depressants like benzodiazepines.
Fluticasone; Umeclidinium; Vilanterol: (Moderate) There is the potential for umeclidinium to have additive anticholinergic effects when administered with other anticholinergics or antimuscarinics. Per the manufaturer, avoid concomitant administration of umeclidinium with other anticholinergic medications when possible.
Fosinopril; Hydrochlorothiazide, HCTZ: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Galantamine: (Moderate) The therapeutic benefits of galantamine, a cholinesterase inhibitor, may be diminished during chronic co-administration with antimuscarinics or medications with potent anticholinergic activity. When concurrent use is not avoidable, the patient should be monitored for cognitive decline and anticholinergic side effects. Clinicians should generally avoid multiple medications with anticholinergic activity in the patient with dementia. Some of the common selective antimuscarinic drugs for bladder problems, (such as oxybutynin, darifenacin, trospium, fesoterodine, tolerodine, or solifenacin), do not routinely cause problems with medications used for dementia, but may cause anticholinergic side effects in some patients. Atropine may be used to offset bradycardia in cholinesterase inhibitor overdose.
Glucagon: (Major) The concomitant use of intravenous glucagon and anticholinergics increases the risk of gastrointestinal adverse reactions due to additive effects on inhibition of gastrointestinal motility. Concomitant use is not recommended.
Glycopyrronium: (Moderate) Although glycopyrronium is minimally absorbed into the systemic circulation after topical application, there is the potential for glycopyrronium to have additive anticholinergic effects when administered with other antimuscarinics. Per the manufaturer, avoid concomitant administration of glycopyrronium with other anticholinergic medications.
Guanidine: (Major) The muscarinic actions of drugs known as parasympathomimetics, including both direct cholinergic receptor agonists and cholinesterase inhibitors, can antagonize the antimuscarinic actions of anticholinergic drugs, and vice versa.
Homatropine; Hydrocodone: (Moderate) Monitor for signs of urinary retention or reduced gastric motility during concomitant hydrocodone and dicyclomine use. Concomitant use may increase the risk of urinary retention and/or severe constipation, which may lead to paralytic ileus.
Hydrochlorothiazide, HCTZ: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Hydrochlorothiazide, HCTZ; Moexipril: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Hydrocodone: (Moderate) Monitor for signs of urinary retention or reduced gastric motility during concomitant hydrocodone and dicyclomine use. Concomitant use may increase the risk of urinary retention and/or severe constipation, which may lead to paralytic ileus.
Hydrocodone; Ibuprofen: (Moderate) Monitor for signs of urinary retention or reduced gastric motility during concomitant hydrocodone and dicyclomine use. Concomitant use may increase the risk of urinary retention and/or severe constipation, which may lead to paralytic ileus.
Hydromorphone: (Moderate) Monitor patients for signs of urinary retention or reduced gastric motility when hydromorphone is used concomitantly with an anticholinergic drug. The concomitant use of hydromorphone and anticholinergic drugs may increase risk of urinary retention and/or severe constipation, which may lead to paralytic ileus. Opiates increase the tone and decrease the propulsive contractions of the smooth muscle of the gastrointestinal tract. Prolongation of the gastrointestinal transit time may be the mechanism of the constipating effect.
Hydroxyzine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Ibritumomab Tiuxetan: (Moderate) Use anticholinergics, such as dicyclomine, and concomitant solid oral dosage forms of potassium chloride with caution due to risk for gastrointestinal mucosal injury. Anticholinergics may decrease gastric motility and increase the transit time of solid oral dosage forms of potassium chloride leading to prolonged contact with the gastrointestinal mucosa.
Ibuprofen; Oxycodone: (Moderate) Monitor for signs of urinary retention or reduced gastric motility during concomitant oxycodone and dicyclomine use. Concomitant use may increase the risk of urinary retention and/or severe constipation, which may lead to paralytic ileus.
Imipramine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant tricyclic antidepressant and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
IncobotulinumtoxinA: (Moderate) The use of systemic antimuscarinic/anticholinergic agents following the administration of botulinum toxins may result in a potentiation of systemic anticholinergic effects (e.g., blurred vision, dry mouth, constipation, or urinary retention).
Ipratropium: (Moderate) Although ipratropium is minimally absorbed into the systemic circulation after inhalation, there is the potential for additive anticholinergic effects when administered with other antimuscarinic or anticholinergic medications. Per the manufacturer, avoid coadministration.
Ipratropium; Albuterol: (Moderate) Although ipratropium is minimally absorbed into the systemic circulation after inhalation, there is the potential for additive anticholinergic effects when administered with other antimuscarinic or anticholinergic medications. Per the manufacturer, avoid coadministration.
Irbesartan; Hydrochlorothiazide, HCTZ: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Itraconazole: (Moderate) Antimuscarinics can raise intragastric pH. This effect may decrease the oral bioavailability of itraconazole; antimuscarinics should be used cautiously in patients receiving itraconazole.
Levocetirizine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant cetirizine and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Levodopa: (Minor) Anticholinergics can potentiate the dopaminergic effects of levodopa. While some patients may benefit from this interaction, clinicians should be ready to decrease doses of levodopa if an antimuscarinic is added.
Levorphanol: (Moderate) Monitor patients for signs of urinary retention or reduced gastric motility when levorphanol is used concomitantly with an anticholinergic drug. The concomitant use of levorphanol and anticholinergic drugs may increase risk of urinary retention and/or severe constipation, which may lead to paralytic ileus. Opiates increase the tone and decrease the propulsive contractions of the smooth muscle of the gastrointestinal tract. Prolongation of the gastrointestinal transit time may be the mechanism of the constipating effect.
Linaclotide: (Moderate) Anticholinergics can promote constipation and pharmacodynamically oppose the action of drugs used for the treatment of constipation or constipation-associated irritable bowel syndrome, such as linaclotide.
Lisinopril; Hydrochlorothiazide, HCTZ: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Loperamide: (Moderate) Both antidiarrheals and anticholinergics, such as dicyclomine, decrease GI motility. Use of these drugs together may produce additive effects on the GI track; thereby increasing the risk for toxic megacolon.
Loperamide; Simethicone: (Moderate) Both antidiarrheals and anticholinergics, such as dicyclomine, decrease GI motility. Use of these drugs together may produce additive effects on the GI track; thereby increasing the risk for toxic megacolon.
Lorazepam: (Moderate) Dicyclomine can cause drowsiness, so it should be used cautiously in patients receiving CNS depressants like benzodiazepines.
Losartan; Hydrochlorothiazide, HCTZ: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Loxapine: (Moderate) Loxapine has anticholinergic activity. The concomitant use of loxapine and other anticholinergic drugs can increase the risk of anticholinergic adverse reactions including exacerbation of glaucoma, constipation, and urinary retention. Depending on the agent used, additive drowsiness/dizziness may also occur.
Lubiprostone: (Moderate) Antimuscarinic drugs can promote constipation and pharmacodynamically oppose the action of drugs used for the treatment of constipation, such as lubiprostone. The clinical significance of these potential interactions is uncertain.
Lurasidone: (Moderate) Antipsychotic agents may disrupt core temperature regulation; therefore, caution is recommended during concurrent use of lurasidone and medications with anticholinergic activity such as antimuscarinics. Concurrent use of lurasidone and medications with anticholinergic activity may contribute to heat-related disorders. Monitor patients for heat intolerance, decreased sweating, or increased body temperature if lurasidone is used with antimuscarinics.
Macimorelin: (Major) Avoid use of macimorelin with drugs that may blunt the growth hormone response to macimorelin, such as antimuscarinic anticholinergic agents. Healthcare providers are advised to discontinue anticholinergics at least 1 week before administering macimorelin. Use of these medications together may impact the accuracy of the macimorelin growth hormone test.
Magnesium Hydroxide: (Moderate) Antacids may inhibit the oral absorption of anticholinergics. Simultaneous oral administration should be avoided when feasible; separate dosing by at least 2 hours to limit an interaction.
Magnesium Salts: (Moderate) Antacids may inhibit the oral absorption of anticholinergics. Simultaneous oral administration should be avoided when feasible; separate dosing by at least 2 hours to limit an interaction.
Maprotiline: (Moderate) Additive anticholinergic effects may be seen when dicyclomine is used concomitantly with other drugs that possess anticholinergic properties, such as maprotiline. Clinicians should note that anticholinergic effects might be seen not only on GI smooth muscle, but also on bladder function, the eye, and temperature regulation. Additive drowsiness may also occur.
Meclizine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Memantine: (Moderate) The adverse effects of anticholinergics, such as dry mouth, urinary hesitancy or blurred vision may be enhanced with use of memantine; dosage adjustments of the anticholinergic drug may be required when memantine is coadministered. In addition, preliminary evidence indicates that chronic anticholinergic use in patients with Alzheimer's Disease may possibly have an adverse effect on cognitive function. Therefore, the effectiveness of drugs used in the treatment of Alzheimer's such as memantine, may be adversely affected by chronic antimuscarinic therapy.
Meperidine: (Moderate) Monitor patients for signs of urinary retention or reduced gastric motility when meperidine is used concomitantly with an anticholinergic drug. The concomitant use of meperidine and anticholinergic drugs may increase risk of urinary retention and/or severe constipation, which may lead to paralytic ileus. Opiates increase the tone and decrease the propulsive contractions of the smooth muscle of the gastrointestinal tract. Prolongation of the gastrointestinal transit time may be the mechanism of the constipating effect.
Meprobamate: (Moderate) Dicyclomine can cause drowsiness, so it should be used cautiously in patients receiving CNS depressants like anxiolytics, sedatives, and hypnotics.
Methadone: (Moderate) Monitor patients for signs of urinary retention or reduced gastric motility when methadone is used concomitantly with an anticholinergic drug. The concomitant use of methadone and anticholinergic drugs may increase risk of urinary retention and/or severe constipation, which may lead to paralytic ileus. Opiates increase the tone and decrease the propulsive contractions of the smooth muscle of the gastrointestinal tract. Prolongation of the gastrointestinal transit time may be the mechanism of the constipating effect.
Metoclopramide: (Moderate) Drugs with significant antimuscarinic activity, such as anticholinergics and antimuscarinics, may slow GI motility and thus may reduce the prokinetic actions of metoclopramide. Monitor patients for an increase in gastrointestinal complaints, such as reflux or constipation. Additive drowsiness may occur as well. The clinical significance is uncertain.
Metolazone: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Metoprolol; Hydrochlorothiazide, HCTZ: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Midazolam: (Moderate) Dicyclomine can cause drowsiness, so it should be used cautiously in patients receiving CNS depressants like benzodiazepines.
Molindone: (Moderate) Antipsychotics are associated with anticholinergic effects; therefore, additive effects may be seen during concurrent use of molindone and other drugs having anticholinergic activity such as antimuscarinics. Clinicians should note that antimuscarinic effects may be seen not only on GI smooth muscle, but also on bladder function, the eye, and temperature regulation. Additive drowsiness or other CNS effects may also occur.
Morphine: (Moderate) Monitor for signs of urinary retention or reduced gastric motility during concomitant morphine and dicyclomine use. Concomitant use may increase the risk of urinary retention and/or severe constipation, which may lead to paralytic ileus.
Morphine; Naltrexone: (Moderate) Monitor for signs of urinary retention or reduced gastric motility during concomitant morphine and dicyclomine use. Concomitant use may increase the risk of urinary retention and/or severe constipation, which may lead to paralytic ileus.
Nabilone: (Moderate) Concurrent use of nabilone with anticholinergics may result in pronounced tachycardia and drowsiness.
Nalbuphine: (Moderate) Monitor patients for signs of urinary retention or reduced gastric motility when nalbuphine is used concomitantly with an anticholinergic drug. The concomitant use of nalbuphine and anticholinergic drugs may increase risk of urinary retention and/or severe constipation, which may lead to paralytic ileus. Opiates increase the tone and decrease the propulsive contractions of the smooth muscle of the gastrointestinal tract. Prolongation of the gastrointestinal transit time may be the mechanism of the constipating effect.
Neostigmine: (Major) The muscarinic actions of neostigmine can antagonize the antimuscarinic actions of dicyclomine and vice-versa.
Neostigmine; Glycopyrrolate: (Major) The muscarinic actions of neostigmine can antagonize the antimuscarinic actions of dicyclomine and vice-versa.
Nortriptyline: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant tricyclic antidepressant and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Olanzapine: (Moderate) Additive anticholinergic effects may be seen when olanzapine and anticholinergics are used concomitantly; use with caution. Use of olanzapine and other drugs with anticholinergic activity can increase the risk for severe gastrointestinal adverse reactions related to hypomotility. Olanzapine exhibits anticholinergic activity. Adverse effects may be seen not only on GI smooth muscle, but also on bladder function, the CNS, the eye, and temperature regulation. Additive drowsiness may also occur, depending on the anticholinergic agent used.
Olanzapine; Fluoxetine: (Moderate) Additive anticholinergic effects may be seen when olanzapine and anticholinergics are used concomitantly; use with caution. Use of olanzapine and other drugs with anticholinergic activity can increase the risk for severe gastrointestinal adverse reactions related to hypomotility. Olanzapine exhibits anticholinergic activity. Adverse effects may be seen not only on GI smooth muscle, but also on bladder function, the CNS, the eye, and temperature regulation. Additive drowsiness may also occur, depending on the anticholinergic agent used.
Olanzapine; Samidorphan: (Moderate) Additive anticholinergic effects may be seen when olanzapine and anticholinergics are used concomitantly; use with caution. Use of olanzapine and other drugs with anticholinergic activity can increase the risk for severe gastrointestinal adverse reactions related to hypomotility. Olanzapine exhibits anticholinergic activity. Adverse effects may be seen not only on GI smooth muscle, but also on bladder function, the CNS, the eye, and temperature regulation. Additive drowsiness may also occur, depending on the anticholinergic agent used.
Oliceridine: (Moderate) Monitor patients for signs of urinary retention or reduced gastric motility when oliceridine is used with dicyclomine. Use of anticholinergics may increase the risk of urinary retention and/or severe constipation, which may lead to paralytic ileus.
Olmesartan; Amlodipine; Hydrochlorothiazide, HCTZ: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Olmesartan; Hydrochlorothiazide, HCTZ: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Omeprazole; Sodium Bicarbonate: (Moderate) Separate the time of administration of oral dicyclomine and oral sodium bicarbonate by at least 2 hours. Simultaneous coadministration may decrease oral dicyclomine absorption and reduce efficacy.
OnabotulinumtoxinA: (Moderate) The use of systemic antimuscarinic/anticholinergic agents following the administration of botulinum toxins may result in a potentiation of systemic anticholinergic effects (e.g., blurred vision, dry mouth, constipation, or urinary retention).
Orphenadrine: (Moderate) Additive anticholinergic effects may be seen when dicyclomine is used concomitantly with other drugs that possess anticholinergic properties, such as orphenadrine. Clinicians should note that anticholinergic effects might be seen not only on GI smooth muscle, but also on bladder function, the eye, and temperature regulation. Additive drowsiness may also occur.
Oxazepam: (Moderate) Dicyclomine can cause drowsiness, so it should be used cautiously in patients receiving CNS depressants like benzodiazepines.
Oxycodone: (Moderate) Monitor for signs of urinary retention or reduced gastric motility during concomitant oxycodone and dicyclomine use. Concomitant use may increase the risk of urinary retention and/or severe constipation, which may lead to paralytic ileus.
Oxymorphone: (Moderate) Monitor patients for signs of urinary retention or reduced gastric motility when oxymorphone is used concomitantly with an anticholinergic drug. The concomitant use of oxymorphone and anticholinergic drugs may increase risk of urinary retention and/or severe constipation, which may lead to paralytic ileus. Opiates increase the tone and decrease the propulsive contractions of the smooth muscle of the gastrointestinal tract. Prolongation of the gastrointestinal transit time may be the mechanism of the constipating effect.
Paroxetine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant anticholinergic medication and paroxetine use. Concomitant use may result in additive anticholinergic adverse effects.
Pentazocine; Naloxone: (Moderate) Monitor patients for signs of urinary retention or reduced gastric motility when pentazocine is used concomitantly with an anticholinergic drug. The concomitant use of pentazocine and anticholinergic medications may increase risk of urinary retention and/or severe constipation, which may lead to paralytic ileus. Opiates increase the tone and decrease the propulsive contractions of the smooth muscle of the gastrointestinal tract. Prolongation of the gastrointestinal transit time may be the mechanism of the constipating effect.
Pentobarbital: (Moderate) Dicyclomine can cause drowsiness, so it should be used cautiously in patients receiving CNS depressants like barbiturates.
Perphenazine: (Moderate) Additive anticholinergic effects may be seen when anticholinergics are used concomitantly with phenothiazines, including perphenazine. Clinicians should note that antimuscarinic effects may be seen not only on GI smooth muscle, but also on bladder function, the eye, and temperature regulation. Additive drowsiness or other additive CNS effects may also occur.
Perphenazine; Amitriptyline: (Moderate) Additive anticholinergic effects may be seen when anticholinergics are used concomitantly with phenothiazines, including perphenazine. Clinicians should note that antimuscarinic effects may be seen not only on GI smooth muscle, but also on bladder function, the eye, and temperature regulation. Additive drowsiness or other additive CNS effects may also occur. (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant tricyclic antidepressant and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Phenobarbital: (Moderate) Dicyclomine can cause drowsiness, so it should be used cautiously in patients receiving CNS depressants like phenobarbital.
Phenobarbital; Hyoscyamine; Atropine; Scopolamine: (Moderate) Dicyclomine can cause drowsiness, so it should be used cautiously in patients receiving CNS depressants like phenobarbital.
Phentermine; Topiramate: (Moderate) Monitor for decreased sweating and increased body temperature, especially in hot weather, during concomitant use of topiramate and other drugs that predispose persons to heat-related disorders, such as anticholinergic medications. Concomitant use increases the risk for oligohidrosis and hyperthermia.
Physostigmine: (Major) The muscarinic actions of physostigmine can antagonize the antimuscarinic actions of dicyclomine and vice-versa.
Pilocarpine: (Major) The muscarinic actions of drugs known as parasympathomimetics, including both direct cholinergic receptor agonists and cholinesterase inhibitors, can antagonize the antimuscarinic actions of anticholinergic drugs, and vice versa.
Potassium Bicarbonate: (Moderate) Use anticholinergics, such as dicyclomine, and concomitant solid oral dosage forms of potassium chloride with caution due to risk for gastrointestinal mucosal injury. Anticholinergics may decrease gastric motility and increase the transit time of solid oral dosage forms of potassium chloride leading to prolonged contact with the gastrointestinal mucosa.
Potassium Chloride: (Moderate) Use anticholinergics, such as dicyclomine, and concomitant solid oral dosage forms of potassium chloride with caution due to risk for gastrointestinal mucosal injury. Anticholinergics may decrease gastric motility and increase the transit time of solid oral dosage forms of potassium chloride leading to prolonged contact with the gastrointestinal mucosa.
Pralidoxime: (Major) The muscarinic actions of drugs known as parasympathomimetics, including both direct cholinergic receptor agonists and cholinesterase inhibitors, can antagonize the antimuscarinic actions of anticholinergic drugs, and vice versa.
Pramlintide: (Major) Pramlintide therapy should not be considered in patients taking medications that alter gastric motility, such as anticholinergics. Pramlintide slows gastric emptying and the rate of nutrient delivery to the small intestine. Medications that have depressive effects on GI could potentiate the actions of pramlintide.
Procainamide: (Moderate) The anticholinergic effects of procainamide may be significant and may be enhanced when combined with anticholinergics. Anticholinergic agents administered concurrently with procainamide may produce additive antivagal effects on AV nodal conduction, although this is not as well documented for procainamide as for quinidine.
Prochlorperazine: (Moderate) Additive anticholinergic effects may be seen when anticholinergics are used concomitantly with phenothiazines, including prochlorperazine. Clinicians should note that antimuscarinic effects may be seen not only on GI smooth muscle, but also on bladder function, the eye, and temperature regulation. Additive drowsiness or other additive CNS effects may also occur.
Promethazine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant promethazine and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Promethazine; Dextromethorphan: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant promethazine and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Promethazine; Phenylephrine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant promethazine and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Protriptyline: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant tricyclic antidepressant and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Pseudoephedrine; Triprolidine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Pyridostigmine: (Major) The muscarinic actions of pyridoostigmine can antagonize the antimuscarinic actions of dicyclomine and vice-versa.
Quazepam: (Moderate) Dicyclomine can cause drowsiness, so it should be used cautiously in patients receiving CNS depressants like benzodiazepines.
Quetiapine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant quetiapine and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Quinapril; Hydrochlorothiazide, HCTZ: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Quinidine: (Moderate) Additive anticholinergic effects may be seen when dicyclomine is used concomitantly with other drugs that possess anticholinergic properties, such as quinidine. Clinicians should note that anticholinergic effects might be seen not only on GI smooth muscle, but also on bladder function, the eye, and temperature regulation. Additive drowsiness may also occur.
Rasagiline: (Moderate) MAOIs exhibit secondary anticholinergic actions. Additive anticholinergic effects may be seen when MAOIs are used concomitantly with antimuscarinics. Clinicians should note that antimuscarinic effects might be seen not only on GI smooth muscle, but also on bladder function, the eye, and temperature regulation. Additive CNS effects are also possible when many of these drugs are combined with MAOIs.
Remifentanil: (Moderate) Monitor patients for signs of urinary retention or reduced gastric motility when remifentanil is used concomitantly with an anticholinergic drug. The concomitant use of remifentanil and anticholinergic drugs may increase risk of urinary retention and/or severe constipation, which may lead to paralytic ileus. Opiates increase the tone and decrease the propulsive contractions of the smooth muscle of the gastrointestinal tract. Prolongation of the gastrointestinal transit time may be the mechanism of the constipating effect.
Remimazolam: (Moderate) Dicyclomine can cause drowsiness, so it should be used cautiously in patients receiving CNS depressants like benzodiazepines.
Revefenacin: (Moderate) Although revefenacin is minimally absorbed into the systemic circulation after inhalation, there is the potential for additive anticholinergic effects when administered with other antimuscarinics. Avoid concomitant administration with other anticholinergic and antimucarinic medications.
RimabotulinumtoxinB: (Moderate) The use of systemic antimuscarinic/anticholinergic agents following the administration of botulinum toxins may result in a potentiation of systemic anticholinergic effects (e.g., blurred vision, dry mouth, constipation, or urinary retention).
Rivastigmine: (Moderate) The therapeutic benefits of rivastigmine, a cholinesterase inhibitor, may be diminished during chronic co-administration with antimuscarinics or medications with potent anticholinergic activity. When concurrent use is not avoidable, the patient should be monitored for cognitive decline and anticholinergic side effects. Clinicians should generally avoid multiple medications with anticholinergic activity in the patient with dementia. Some of the common selective antimuscarinic drugs for bladder problems, (such as oxybutynin, darifenacin, trospium, fesoterodine, tolerodine, or solifenacin), do not routinely cause problems with medications used for dementia, but may cause anticholinergic side effects in some patients. Atropine may be used to offset bradycardia in cholinesterase inhibitor overdose.
Secobarbital: (Moderate) Dicyclomine can cause drowsiness, so it should be used cautiously in patients receiving CNS depressants like barbiturates.
Secretin: (Major) Discontinue anticholinergic medications at least 5 half-lives before administering secretin. Patients who are receiving anticholinergics at the time of stimulation testing may be hyporesponsive to secretin stimulation and produce a false result. Consider additional testing and clinical assessments for aid in diagnosis.
Sedating H1-blockers: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Sincalide: (Moderate) Sincalide-induced gallbladder ejection fraction may be affected by anticholinergics. False study results are possible in patients with drug-induced hyper- or hypo-responsiveness; thorough patient history is important in the interpretation of procedure results.
Sodium Bicarbonate: (Moderate) Separate the time of administration of oral dicyclomine and oral sodium bicarbonate by at least 2 hours. Simultaneous coadministration may decrease oral dicyclomine absorption and reduce efficacy.
Sodium Sulfate; Magnesium Sulfate; Potassium Chloride: (Moderate) Use anticholinergics, such as dicyclomine, and concomitant solid oral dosage forms of potassium chloride with caution due to risk for gastrointestinal mucosal injury. Anticholinergics may decrease gastric motility and increase the transit time of solid oral dosage forms of potassium chloride leading to prolonged contact with the gastrointestinal mucosa.
Solifenacin: (Moderate) Additive anticholinergic effects may be seen when drugs with antimuscarinic properties like solifenacin are used concomitantly with other antimuscarinics. Blurred vision and dry mouth would be common effects. Clinicians should note that additive antimuscarinic effects may be seen not only on GI smooth muscle, but also on bladder function, the CNS, the eye, and temperature regulation. Additive drowsiness may also occur.
Spironolactone; Hydrochlorothiazide, HCTZ: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Sufentanil: (Moderate) Monitor patients for signs of urinary retention or reduced gastric motility when sufentanil is used concomitantly with an anticholinergic drug. The concomitant use of sufentanil and anticholinergic drugs may increase risk of urinary retention and/or severe constipation, which may lead to paralytic ileus. Opiates increase the tone and decrease the propulsive contractions of the smooth muscle of the gastrointestinal tract. Prolongation of the gastrointestinal transit time may be the mechanism of the constipating effect.
Tapentadol: (Moderate) Tapentadol should be used cautiously with anticholinergic medications since additive depressive effects on GI motility or bladder function may occur. Monitor patients for signs of urinary retention or reduced gastric motility. Opiates increase the tone and decrease the propulsive contractions of the smooth muscle of the gastrointestinal tract. Prolongation of the gastrointestinal transit time may be the mechanism of the constipating effect. Opiate analgesics combined with antimuscarinics can cause severe constipation or paralytic ileus, especially with chronic use. Additive CNS effects like drowsiness or dizziness may also occur.
Tegaserod: (Major) Drugs that exert significant anticholinergic properties such as antimuscarinics may pharmacodynamically oppose the effects of prokinetic agents such as tegaserod. Avoid administering antimuscarinics along with tegaserod under most circumstances. Inhaled respiratory antimuscarinics, such as ipratropium, are unlikely to interact with tegaserod. Ophthalmic anticholinergics may interact if sufficient systemic absorption of the eye medication occurs.
Telmisartan; Hydrochlorothiazide, HCTZ: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Temazepam: (Moderate) Dicyclomine can cause drowsiness, so it should be used cautiously in patients receiving CNS depressants like benzodiazepines.
Tenapanor: (Moderate) Anticholinergics can promote constipation and pharmacodynamically oppose the action of drugs used for the treatment of constipation or constipation-associated irritable bowel syndrome, such as tenapanor.
Thiazide diuretics: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Thioridazine: (Moderate) Additive anticholinergic effects may be seen when drugs with anticholinergic properties like thioridazine are used concomitantly with anticholinergic agents. Adverse effects may be seen not only on GI smooth muscle, but also on bladder function, the CNS, the eye, and temperature regulation. Additive drowsiness may also occur, depending on the interacting agent.
Thiothixene: (Moderate) Anticholinergics may have additive effects with thiothixene, an antipsychotic with the potential for anticholinergic activity. Monitor for anticholinergic-related adverse effects such as xerostomia, blurred vision, constipation, and urinary retention during concurrent use.
Tiotropium: (Major) Avoid concomitant use of anticholinergic medications and tiotropium due to increased risk for anticholinergic adverse effects.
Tiotropium; Olodaterol: (Major) Avoid concomitant use of anticholinergic medications and tiotropium due to increased risk for anticholinergic adverse effects.
Tolterodine: (Moderate) Additive anticholinergic effects may be seen when tolterodine is used concomitantly with other antimuscarinics. When possible, avoid concurrent use, especially in the elderly, who are more susceptible to the anticholinergic effects. Consider alternatives to these other medications, if available. Clinicians should note that antimuscarinic effects might be seen not only on bladder smooth muscle, but also on GI function, the eye, and temperature regulation. Blurred vision, constipation, and dry mouth may be more prominent additive effects. With many of the listed agents, additive drowsiness may also occur when combined.
Topiramate: (Moderate) Monitor for decreased sweating and increased body temperature, especially in hot weather, during concomitant use of topiramate and other drugs that predispose persons to heat-related disorders, such as anticholinergic medications. Concomitant use increases the risk for oligohidrosis and hyperthermia.
Tramadol: (Moderate) Monitor for signs of urinary retention or reduced gastric motility during concomitant tramadol and dicyclomine use. Concomitant use may increase the risk of urinary retention and/or severe constipation, which may lead to paralytic ileus.
Tramadol; Acetaminophen: (Moderate) Monitor for signs of urinary retention or reduced gastric motility during concomitant tramadol and dicyclomine use. Concomitant use may increase the risk of urinary retention and/or severe constipation, which may lead to paralytic ileus.
Triamterene; Hydrochlorothiazide, HCTZ: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Triazolam: (Moderate) Dicyclomine can cause drowsiness, so it should be used cautiously in patients receiving CNS depressants like benzodiazepines.
Tricyclic antidepressants: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant tricyclic antidepressant and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Trifluoperazine: (Moderate) Additive anticholinergic effects may be seen when anticholinergics are used concomitantly with phenothiazines, including trifluoperazine. Clinicians should note that antimuscarinic effects may be seen not only on GI smooth muscle, but also on bladder function, the eye, and temperature regulation. Additive drowsiness or other additive CNS effects may also occur.
Trimethobenzamide: (Moderate) Trimethobenzamide has CNS depressant effects and may cause drowsiness. The concurrent use of trimethobenzamide with other medications that cause CNS depression, like the anticholinergics, may potentiate the effects of either trimethobenzamide or the anticholinergic.
Trimipramine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant tricyclic antidepressant and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Triprolidine: (Moderate) Monitor for signs or symptoms of anticholinergic toxicity during concomitant sedating H1-blocker and dicyclomine use. Concomitant use may result in additive anticholinergic adverse effects.
Trospium: (Moderate) Additive anticholinergic effects may be seen when trospium is used concomitantly with other antimuscarinics. When possible, avoid concurrent use, especially in the elderly, who are more susceptible to the anticholinergic effects. Consider alternatives to these other medications, if available. Clinicians should note that antimuscarinic effects might be seen not only on bladder smooth muscle, but also on GI function, the eye, and temperature regulation. Blurred vision, constipation, and dry mouth may be more prominent additive effects. With many of the listed agents, additive drowsiness may also occur when combined with trospium.
Umeclidinium: (Moderate) There is the potential for umeclidinium to have additive anticholinergic effects when administered with other anticholinergics or antimuscarinics. Per the manufaturer, avoid concomitant administration of umeclidinium with other anticholinergic medications when possible.
Umeclidinium; Vilanterol: (Moderate) There is the potential for umeclidinium to have additive anticholinergic effects when administered with other anticholinergics or antimuscarinics. Per the manufaturer, avoid concomitant administration of umeclidinium with other anticholinergic medications when possible.
Valsartan; Hydrochlorothiazide, HCTZ: (Minor) Coadministration of thiazides and antimuscarinics (e.g., atropine and biperiden) may result in increased bioavailability of the thiazide. This is apparently a result of a decrease in gastrointestinal motility and rate of stomach emptying by the antimuscarinic agent. In addition, diuretics can increase urinary frequency, which may aggravate bladder symptoms.
Vibegron: (Moderate) Vibegron should be administered with caution in patients taking anticholinergics because of potential for an increased risk of urinary retention. Monitor for symptoms of urinary difficulties or urinary retention. Patients may note constipation or dry mouth with use of these drugs together.
Zaleplon: (Moderate) Dicyclomine can cause drowsiness, so it should be used cautiously in patients receiving CNS depressants like anxiolytics, sedatives, and hypnotics.
Zolpidem: (Moderate) Dicyclomine can cause drowsiness, so it should be used cautiously in patients receiving CNS depressants like anxiolytics, sedatives, and hypnotics.
Zonisamide: (Moderate) Zonisamide use is associated with case reports of decreased sweating, hyperthermia, heat intolerance, or heat stroke and should be used with caution in combination with other drugs that may also predispose patients to heat-related disorders like anticholinergics.
Dicyclomine is an antimuscarinic, anticholinergic agent. Based on animal studies, there are 2 main mechanisms of action. There is a nonspecific, local, direct spasmolytic (musculotropic) action on the smooth muscle of the gastrointestinal (GI) tract via antagonism of bradykinin- and histamine-induced spasms, thereby decreasing muscular tone and motility. Dicyclomine also can relieve GI smooth muscle spasm via a specific anticholinergic effect (antimuscarinic) at the acetylcholine-receptor sites with approximately 1/8 the milligram potency of atropine. Dicyclomine, like many antimuscarinic agents, may inhibit the secretion of saliva and sweat, decrease GI secretions and motility, cause drowsiness, dilate the pupils, increase heart rate, and depress motor function.
Dicyclomine is administered orally and intramuscularly. The volume of distribution is 3.65 L/kg. The specific mechanisms of elimination have not been determined. Approximately 80% of an oral dose is excreted in the urine and about 9% in the feces. The mean half-life of plasma elimination in a study was determined to be approximately 1.8 hours when plasma concentrations were measured for 9 hours after a single dose. In subsequent studies, plasma concentrations were followed for up to 25 hours after a single dose, showing a secondary phase of elimination with a somewhat longer half-life.
Affected cytochrome P450 isoenzymes and drug transporters: None
-Route-Specific Pharmacokinetics
Oral Route
Dicyclomine is absorbed rapidly from the GI tract and reaches peak plasma concentrations within 1 to 1.5 hours following oral administration.
Intramuscular Route
Intramuscular dicyclomine is nearly twice as bioavailable as oral dicyclomine.
-Special Populations
Hepatic Impairment
The effects of hepatic impairment on the pharmacokinetics of dicyclomine have not been studied.
Renal Impairment
The effects of renal impairment on the pharmacokinetics of dicyclomine have not been studied. Dicyclomine is known to be substantially excreted by the kidney.