Calcium chloride is an ionic compound of calcium and chlorine. Calcium is the most abundant cation and the fifth most common inorganic element in the human body. Calcium is essential for the maintenance of the nervous, muscular, and skeletal systems, and for cell membrane and capillary permeability. Its role in bone structure and muscle contraction is well known, but calcium is also important for blood coagulation, nerve conduction, and electrical conduction in the myocardium. In general, calcium salts are used to treat or prevent calcium depletion. Calcium is used for the temporary control of cardiac arrhythmias; however, parenteral calcium is recommended for the treatment of cardiac arrest or life-threatening cardiac arrhythmias only when associated with hypocalcemia, hyperkalemia, or hypermagnesemia. Calcium chloride contains more elemental calcium than calcium gluconate (27% elemental calcium compared with 9%) and is the preferred salt form for use in acute hypocalcemia in emergent situations because it is in the ionized form and results in a greater increase in ionized calcium; however, calcium gluconate is usually preferred in the nonarrest setting for mild to moderate, asymptomatic hypocalcemia due to the lower potential for infusion site reactions compared with calcium chloride.
General Administration Information
For storage information, see the specific product information within the How Supplied section.
Route-Specific Administration
Injectable Administration
-Visually inspect parenteral products for particulate matter and discoloration prior to administration whenever solution and container permit.
-Calcium chloride 10% (100 mg/mL) contains 27.2 mg/mL of elemental calcium.
Intravenous Administration
Intermittent IV Infusion
-May dilute in compatible IV solution (i.e., 0.9% Sodium Chloride Injection, 5% Dextrose Injection, 10% Dextrose Injection) to a usual concentration of 10 to 40 mg/mL.
-Administration into a large vein or a central line is preferred; avoid extravasation. In a safety analysis of peripheral intravenous administration of calcium chloride solutions to adult patients, concentrations of approximately 3 mg/mL resulted in a low incidence of infusion site reactions.-Neonates: Concentrations of 1 mg/mL or less have been recommended for peripheral lines for neonates.
-Do not administer via scalp vein catheter.
-Generally, infuse a bolus dose over 30 to 60 minutes. Calcium chloride may be administered at a rate not exceeding 100 mg/minute.
IV Push
-Inject by slow IV injection, preferably in a deep or central vein. The product labeling recommends an absolute maximum rate of 1 mL/minute (100 mg/minute); however, for life-threatening cardiac arrhythmias during cardiopulmonary resuscitation, bolus doses are given over 2 to 5 minutes. After injection, the patient should remain recumbent for a short time.
Other Injectable Administration
Intraosseous Administration
NOTE: Calcium chloride is not FDA-approved for intraosseous administration.
-During pediatric cardiopulmonary resuscitation, the same dosage may be given via the intraosseous route if IV access is unsuccessful or not feasible.
Intracardiac Administration
-In cardiac resuscitation, calcium chloride, in the appropriate intracardiac dose, can be injected into the ventricular cavity. Take care to avoid injection into the cardiac muscle.
Intravenous administration of calcium chloride in patients with local trauma may result in calcinosis cutis due to a transient increase in local calcium concentrations. Calcinosis cutis may occur with or without extravasation of calcium chloride and is characterized by abnormal dermal calcium deposits. Symptoms may include papules, plaques, or nodules associated with erythema, swelling, or induration. Tissue necrosis, ulceration, and secondary infection are the most serious complications. To minimize the risk of tissue necrosis, ulceration, and calcinosis, administer calcium chloride intravenously through a small needle into a large vein. Avoid extravasation or accidental injection into perivascular tissues. Should perivascular infiltration occur, immediately discontinue intravenous administration at that site and treat as needed. Do not administer calcium chloride intramuscularly or subcutaneously to avoid tissue necrosis and calcinosis cutis. Calcium chloride is more irritating to the veins compared with calcium gluconate, and therefore, is not the preferred salt form for routine calcium maintenance and supplementation, particularly in pediatric patients.
Hypercalcemia may occur with excess intake of calcium. It rarely occurs if appropriate doses of calcium are administered to otherwise healthy patients; however, patients with renal failure, patients receiving vitamin D, patients with electrolyte imbalance (i.e., hyponatremia, hyperkalemia), and patients with prolonged immobility can develop hypercalcemia readily. Signs and symptoms of hypercalcemia include anorexia, constipation, nausea/vomiting, drowsiness, hypertension, polyuria, and premature ventricular contractions (PVCs). Severe hypercalcemia (calcium more than 12 mg/dL) may result in confusion, delirium, stupor, and coma. Concentrations more than 15 mg/dL may be life-threatening. Calcium chloride infusion can cause hypotension (dizziness and syncope), flushing, nausea/vomiting, tingling sensation (i.e., paresthesias), and a calcium or chalky taste (i.e., dysgeusia). Rapid IV injection can cause peripheral vasodilation, sinus bradycardia or AV block, cardiac arrhythmias (including ventricular fibrillation), and/or cardiac arrest, especially in the digitalized patient. Cardiac monitoring is recommended during IV infusion to avoid serious cardiac adverse events.
A rare, but serious, side effect of calcium administration is calcific nephrolithiasis.
Calcium chloride injection contains aluminum. Thus, aluminum toxicity may occur with prolonged administration in high-risk patients, including those with renal impairment and premature neonates. Premature neonates are at particular risk for aluminum toxicity because of immature renal function and they require large amounts of calcium and phosphate solutions, which contain aluminum. Research indicates that patients with renal impairment, who receive parenteral aluminum at rates greater than 4 to 5 mcg/kg/day, may develop aluminum toxicity (CNS and bone toxicity). Tissue loading may occur at lower administration rates.
Calcium salts are contraindicated in patients with hypercalcemia.
Calcium chloride is contraindicated in patients with ventricular fibrillation or asystole and electromechanical dissociation. Calcium chloride is not recommended for routine use during cardiopulmonary resuscitation, except when indications exist to counterbalance electrolyte disturbances or certain drug toxicities. Calcium chloride is contraindicated in patients with digitalis toxicity because of an increased risk of developing cardiac arrhythmias. Cardiac glycosides and calcium chloride both increase intracellular calcium, and calcium chloride can worsen digitalis toxicity. Rapid injection of calcium chloride (more than 100 mg/minute) may cause vasodilation, hypotension, bradycardia, arrhythmias, syncope, and cardiac arrest. Cardiac monitoring is recommended during IV administration to avoid serious cardiac adverse events.
Do not administer calcium chloride by intramuscular administration or subcutaneous administration to avoid tissue necrosis and calcinosis cutis. To minimize the risk of tissue necrosis, ulceration, and calcinosis, administer calcium chloride intravenously through a small needle into a large vein. Avoid extravasation or accidental injection into perivascular tissues. Should perivascular infiltration occur, immediately discontinue intravenous administration at that site and treat as needed.
Initiate calcium chloride at the lowest recommended dose within the recommended dose range for patients with renal impairment or renal failure. Monitor serum calcium concentrations frequently based on the severity of the renal impairment and the risk of a high calcium-phosphorus product (e.g., every 4 hours). The use of calcium chloride in patients with renal impairment may increase the risk of a higher calcium-phosphorus product. Additionally, calcium chloride formulations contain aluminum (content varies with formulation). Aluminum may reach toxic concentrations with prolonged administration in patients with renal impairment. Premature neonates are at particular risk for aluminum toxicity because of immature renal function, and they require large amounts of calcium and phosphate solutions, which contain aluminum. Research indicates that patients with renal impairment, including neonates, who receive parenteral aluminum at rates greater than 4 to 5 mcg/kg/day may accumulate aluminum at concentrations associated with central nervous system and bone toxicity. Tissue loading may occur at lower administration rates. Limit the total daily patient exposure to aluminum to no more than 5 mcg/kg/day when giving calcium chloride injection to patients receiving parenteral nutrition solutions.
Calcium chloride should be used cautiously, if at all, in patients with vitamin D toxicity or hyperparathyroidism. Hypercalcemia is likely to occur in either of these conditions.
Calcium chloride should be used with caution in patients with preexisting hypercalciuria or nephrolithiasis, especially if renal calculi are present.
Calcium chloride should be used with caution in patients with sarcoidosis as hypercalcemia is more likely to occur in these patients.
Administration of calcium chloride for the treatment of acute symptomatic hypocalcemia during pregnancy is not expected to cause major birth defects, miscarriage, or adverse maternal or fetal outcomes. There are risks to the mother and the fetus associated with development of hypocalcemia during pregnancy. Maternal hypocalcemia can result in an increased rate of spontaneous abortion, premature and dysfunctional labor, and possibly preeclampsia. Infants born to mothers with hypocalcemia can develop fetal and neonatal hyperparathyroidism, which in turn can cause fetal and neonatal skeletal demineralization, subperiosteal bone resorption, osteitis fibrosa cystica, and neonatal seizures. Animal reproduction studies have not been conducted with calcium chloride.
Calcium is present in human milk. There is no information on the effects of calcium chloride on the breast-fed infant or on milk production. Administration of the approved recommended dose of calcium chloride injection to the mother is not expected to cause harm to a breast-fed infant. Consider the developmental and health benefits of breast-feeding along with the mother's clinical need for calcium chloride and any potential adverse effects on the breast-fed infant from calcium chloride or the underlying maternal condition.
Calcium-containing IV solutions are contraindicated in neonates who require coadministration of ceftriaxone due to cases of fatal outcomes in which ceftriaxone-calcium precipitates in the lung and kidneys have been reported in both term and premature neonates. In older patients, ceftriaxone and calcium-containing IV solutions may be used concomitantly; however, ceftriaxone must NOT be mixed or administered simultaneously with calcium-containing IV solutions, even via a Y-site or different infusion line at different sites.
-Calcium chloride is 27% elemental calcium, which is equivalent to 270 mg elemental calcium (14 mEq) per gram of calcium chloride.
For the treatment of acute or symptomatic hypocalcemia (i.e., tetany due to hypocalcemia):
Intravenous dosage:
Adults: 1 g IV every 6 hours as needed as determined by serum calcium concentrations and patient response. Alternatively, 2 to 7 mg/kg/hour continuous IV infusion (0.5 to 2 mg/kg/hour elemental calcium) may be administered if symptoms recur after initial IV calcium replacement. Adjust dose based on serum calcium concentrations.
Infants, Children, and Adolescents: 10 to 20 mg/kg/dose (Max: 1 g/dose) IV every 6 hours as needed as determined by serum calcium concentrations and patient response. The FDA-approved dosage is 2.7 to 5 mg/kg/dose IV every 4 to 6 hours as needed. Alternatively, 2 to 7 mg/kg/hour continuous IV infusion (0.5 to 2 mg/kg/hour elemental calcium) may be administered if symptoms recur after initial IV calcium replacement. Adjust dose based on serum calcium concentrations.
Neonates: 10 to 20 mg/kg/dose IV every 6 hours as needed as determined by serum calcium concentrations and patient response. The FDA-approved dosage is 2.7 to 5 mg/kg/dose IV every 4 to 6 hours as needed. Alternatively, 2 to 11 mg/kg/hour continuous IV infusion (0.5 to 3 mg/kg/hour elemental calcium) may be administered if symptoms recur after initial IV calcium replacement. Adjust dose based on serum calcium concentrations. In neonates, continuous infusion of calcium is preferred to IV bolus doses. Calcium chloride is less commonly used for neonatal patients because it is very irritating to the veins.
For the treatment of cardiotoxicity or cardiac arrest associated with hyperkalemia, hypermagnesemia, or ionized hypocalcemia, including during cardiopulmonary resuscitation:
NOTE: Calcium chloride is not recommended for cardiopulmonary arrest in the absence of documented hypocalcemia, calcium-channel blocker overdose, hypermagnesemia, or hyperkalemia. No benefit has been demonstrated for routine use during cardiac arrest and hypercalcemia may occur after calcium administration. The use of calcium during pediatric cardiopulmonary resuscitation has been associated with decreased survival and poor neurologic outcomes.
Intravenous or Intraosseous* dosage:
Adults: 500 to 1,000 mg (5 to 10 mL of a 10% solution) IV or IO; may repeat dose if needed.
Infants, Children, and Adolescents: 20 mg/kg/dose (0.2 mL/kg/dose of a 10% solution) IV or IO (Max: 2 g/dose); may repeat dose if needed. Calcium chloride is preferred over calcium gluconate because it is in the ionized form and leads to a greater increase in ionized calcium.
Neonates: 20 mg/kg/dose (0.2 mL/kg/dose of a 10% solution) IV or IO; may repeat dose if needed. Calcium chloride is preferred over calcium gluconate because it is in the ionized form and leads to a greater increase in ionized calcium.
For nutritional supplementation* to prevent hypocalcemia and maintain nutritional status in patients receiving parenteral nutrition (PN):
NOTE: Calcium gluconate is the preferred salt for PN formulations. Calcium chloride is far more reactive than an equivalent amount of calcium gluconate, therefore solubility curves for calcium gluconate cannot be applied to calcium chloride. Calcium chloride may an acceptable alternative during drug shortages or other situations.
Intravenous dosage:
Adults: 10 to 15 mEq/day IV. Total calcium amounts may be limited due to calcium/phosphate incompatibility. Individualize dosing according to monitoring.
Children weighing more than 50 kg and Adolescents: 10 to 20 mEq/day IV. Total calcium amounts may be limited due to calcium/phosphate incompatibility. Individualize dosing according to monitoring.
Infants and Children weighing 50 kg or less: 0.5 to 4 mEq/kg/day IV. Total calcium amounts may be limited due to calcium/phosphate incompatibility. Individualize dosing according to monitoring.
Neonates: 2 to 4 mEq/kg/day IV. Higher calcium requirements are necessary in premature and term neonates compared with older children; however, total calcium amounts may be limited due to calcium/phosphate incompatibility. Individualize dosing according to monitoring.
For transfusion-induced hypocalcemia prophylaxis*:
-for citrated blood transfusion-induced hypocalcemia prophylaxis:
Intravenous dosage:
Adults: 100 mg (1.4 mEq elemental calcium) IV for each 100 mL of citrated blood infused.
Infants, Children, and Adolescents: 100 mg (1.4 mEq elemental calcium) IV for each 100 mL of citrated blood infused.
-for exchange transfusion-induced hypocalcemia prophylaxis:
Intravenous dosage:
Neonates: 33 mg (approximately 0.465 mEq elemental calcium) IV for each 100 mL of citrated blood infused would be the equivalent dose (based on elemental calcium) to the dose recommendation for calcium gluconate. Most studies have used calcium gluconate for exchange transfusions; however, a study suggested calcium chloride would be the preferred form for use with citrated blood because it is completely ionized. Studies have reported that although decreases in ionized calcium concentrations occurred during exchange transfusion, the decreases were transient and normalized spontaneously and hypocalcemia as a complication did not occur in groups who did not receive calcium supplementation. One study in 18 neonates found no difference in ionized calcium concentrations between patients who received calcium and those who did not. Studies have suggested that routine supplementation is not necessary in most patients and supplementation should be considered in high-risk patients (i.e., very low birth weight infants with complicated history and repeated exchange transfusions).
For the treatment of calcium-channel blocker toxicity*:
Intravenous dosage:
Adults: 1,000 to 2,000 mg (10 to 20 mL of a 10% solution) IV over 5 minutes; may repeat every 10 to 20 minutes for an additional 3 to 4 doses or consider an infusion 20 to 50 mg/kg/hour (0.2 to 0.5 mL/kg/hour). Titrate to effect and administer additional boluses as needed.
Infants, Children, and Adolescents: 20 mg/kg/dose (0.2 mL/kg/dose of a 10% solution) (Max: 2 g/dose) IV over 5 to 10 minutes; if there is a beneficial effect, start 20 to 50 mg/kg/hour (0.2 to 0.5 mL/kg/hour) continuous IV infusion.
Therapeutic Drug Monitoring:
Ionized calcium concentrations are the preferred measure to determine true hypocalcemia. If total serum calcium concentrations are obtained, calcium concentrations should be adjusted if hypoalbuminemia or hyperalbuminemia is present. The corrected calcium concentration may be estimated from the following formula :
-Corrected calcium (mg/dL) = serum calcium (mg/dL) + 0.8 [4 - serum albumin (g/dL)]
Maximum Dosage Limits:
-Adults
Generally, 2 g IV as a single bolus dose.
-Geriatric
Generally, 2 g IV as a single bolus dose.
-Adolescents
Generally, 20 mg/kg/dose (Max: 2 g/dose) IV as a single bolus dose.
-Children
Generally, 20 mg/kg/dose (Max: 2 g/dose) IV as a single bolus dose.
-Infants
Generally, 20 mg/kg/dose IV as a single bolus dose.
-Neonates
Generally, 20 mg/kg/dose IV as a single bolus dose.
Patients with Hepatic Impairment Dosing
Specific guidelines for dosage adjustments in hepatic impairment are not available; it appears that no dosage adjustments are needed.
Patients with Renal Impairment Dosing
Initiate calcium chloride at the lowest recommended dose within the recommended dose range in patients with renal impairment.
*non-FDA-approved indication
Abacavir; Dolutegravir; Lamivudine: (Moderate) Administer dolutegravir 2 hours before or 6 hours after taking supplements containing calcium if given under fasting conditions. When taken with food, dolutegravir and supplements containing calcium can be taken at the same time. Simultaneous administration under fasted conditions may result in reduced bioavailability of dolutegravir.
Aliskiren; Hydrochlorothiazide, HCTZ: (Moderate) Monitor serum calcium concentration during concomitant calcium and thiazide diuretic use due to the risk for hypercalcemia. Thiazide diuretics may decrease urinary calcium excretion and cause intermittent and slight increases in serum calcium.
Amiloride; Hydrochlorothiazide, HCTZ: (Moderate) Monitor serum calcium concentration during concomitant calcium and thiazide diuretic use due to the risk for hypercalcemia. Thiazide diuretics may decrease urinary calcium excretion and cause intermittent and slight increases in serum calcium.
Amlodipine: (Minor) Monitor blood pressure during concurrent use of calcium and calcium-channel blockers. Concomitant use may reduce the response to calcium-channel blockers.
Amlodipine; Atorvastatin: (Minor) Monitor blood pressure during concurrent use of calcium and calcium-channel blockers. Concomitant use may reduce the response to calcium-channel blockers.
Amlodipine; Benazepril: (Minor) Monitor blood pressure during concurrent use of calcium and calcium-channel blockers. Concomitant use may reduce the response to calcium-channel blockers.
Amlodipine; Celecoxib: (Minor) Monitor blood pressure during concurrent use of calcium and calcium-channel blockers. Concomitant use may reduce the response to calcium-channel blockers.
Amlodipine; Olmesartan: (Minor) Monitor blood pressure during concurrent use of calcium and calcium-channel blockers. Concomitant use may reduce the response to calcium-channel blockers.
Amlodipine; Valsartan: (Minor) Monitor blood pressure during concurrent use of calcium and calcium-channel blockers. Concomitant use may reduce the response to calcium-channel blockers.
Amlodipine; Valsartan; Hydrochlorothiazide, HCTZ: (Moderate) Monitor serum calcium concentration during concomitant calcium and thiazide diuretic use due to the risk for hypercalcemia. Thiazide diuretics may decrease urinary calcium excretion and cause intermittent and slight increases in serum calcium. (Minor) Monitor blood pressure during concurrent use of calcium and calcium-channel blockers. Concomitant use may reduce the response to calcium-channel blockers.
Atenolol: (Minor) Calcium antacids (e.g., calcium carbonate) and supplements (e.g., other oral calcium salts) have been reported to reduce the mean peak concentrations by 51% and the AUC of atenolol by 32%. In another study, antacids reduced the AUC of atenolol by 33%. Separate doses of atenolol and calcium-containing antacids or supplements by at least 2 hours to minimize this potential interaction,. However, most clinicians consider the interaction of atenolol with antacids to be of minor clinical significance, since clinical efficacy (heart rate and blood pressure parameters) appear to be unchanged under usual intermittent clinical use.
Atenolol; Chlorthalidone: (Moderate) Monitor serum calcium concentration during concomitant calcium and thiazide diuretic use due to the risk for hypercalcemia. Thiazide diuretics may decrease urinary calcium excretion and cause intermittent and slight increases in serum calcium. (Minor) Calcium antacids (e.g., calcium carbonate) and supplements (e.g., other oral calcium salts) have been reported to reduce the mean peak concentrations by 51% and the AUC of atenolol by 32%. In another study, antacids reduced the AUC of atenolol by 33%. Separate doses of atenolol and calcium-containing antacids or supplements by at least 2 hours to minimize this potential interaction,. However, most clinicians consider the interaction of atenolol with antacids to be of minor clinical significance, since clinical efficacy (heart rate and blood pressure parameters) appear to be unchanged under usual intermittent clinical use.
Atracurium: (Moderate) Concomitant use of neuromuscular blockers and calcium may result in resistance to neuromuscular blockade. Calcium antagonizes the potentiating effect of magnesium on neuromuscular blockade. Also, calcium triggers acetylcholine release, and therefore, may both reduce the sensitivity to neuromuscular blockers and decrease the duration of neuromuscular blockade.
Azilsartan; Chlorthalidone: (Moderate) Monitor serum calcium concentration during concomitant calcium and thiazide diuretic use due to the risk for hypercalcemia. Thiazide diuretics may decrease urinary calcium excretion and cause intermittent and slight increases in serum calcium.
Benazepril; Hydrochlorothiazide, HCTZ: (Moderate) Monitor serum calcium concentration during concomitant calcium and thiazide diuretic use due to the risk for hypercalcemia. Thiazide diuretics may decrease urinary calcium excretion and cause intermittent and slight increases in serum calcium.
Bismuth Subcitrate Potassium; Metronidazole; Tetracycline: (Moderate) Divalent or trivalent cations readily chelate with tetracycline antibiotics, forming insoluble compounds. The oral absorption of these antibiotics will be significantly reduced by other orally administered compounds that contain calcium salts, particularly if the time of administration is within 60 minutes of each other. Calcium salts and tetracyclines should not be administered within 1 to 2 hours of each other, although doxycycline chelates less with calcium than other tetracyclines.
Bismuth Subsalicylate; Metronidazole; Tetracycline: (Moderate) Divalent or trivalent cations readily chelate with tetracycline antibiotics, forming insoluble compounds. The oral absorption of these antibiotics will be significantly reduced by other orally administered compounds that contain calcium salts, particularly if the time of administration is within 60 minutes of each other. Calcium salts and tetracyclines should not be administered within 1 to 2 hours of each other, although doxycycline chelates less with calcium than other tetracyclines.
Bisoprolol; Hydrochlorothiazide, HCTZ: (Moderate) Monitor serum calcium concentration during concomitant calcium and thiazide diuretic use due to the risk for hypercalcemia. Thiazide diuretics may decrease urinary calcium excretion and cause intermittent and slight increases in serum calcium.
Calcifediol: (Moderate) Monitor serum calcium concentrations during concomitant use of high doses of calcium and vitamin D analogs; a dosage adjustment of the vitamin D analog may be needed. Hypercalcemia may be exacerbated by concomitant administration.
Calcipotriene: (Minor) There is evidence that calcipotriene can be absorbed in amounts that are sufficient to produce systemic effects, including elevated serum calcium; hypercalcemia has been observed in normal prescription use. Use calcipotriene cautiously with other agents that can produce hypercalcemia (e.g., calcium salts or supplements including calcium carbonate).
Calcipotriene; Betamethasone: (Minor) There is evidence that calcipotriene can be absorbed in amounts that are sufficient to produce systemic effects, including elevated serum calcium; hypercalcemia has been observed in normal prescription use. Use calcipotriene cautiously with other agents that can produce hypercalcemia (e.g., calcium salts or supplements including calcium carbonate).
Calcitonin: (Moderate) Calcitonin is given to hypercalcemic patients to reduce serum calcium concentrations. For the treatment of hypercalcemia, calcium supplements should be avoided. Calcium salts, including calcium carbonate, can elevate serum calcium concentrations and antagonize the effects of the calcitonin for this condition. For the treatment of osteoporosis adequate intake of calcium salts are necessary in conjunction with calcitonin. An increase in serum calcium concentrations helps to reduce bone resorption and loss of bone mass, and offsets the effect of calcitonin in lowering serum calcium levels.
Calcitriol: (Moderate) Monitor serum calcium concentrations during concomitant use of high doses of calcium and vitamin D analogs; a dosage adjustment of the vitamin D analog may be needed. Hypercalcemia may be exacerbated by concomitant administration.
Calcium Phosphate, Supersaturated: (Moderate) The concomitant use of oral sodium phosphate monobasic monohydrate; sodium phosphate dibasic anhydrous preparations in conjunction with antacids containing calcium (e.g., calcium carbonate, calcium salts) may bind the phosphate in the stomach and reduce its absorption. If the patient requires multiple mineral supplements or concurrent use of antacids, it is prudent to separate the administration of sodium phosphate salts from calcium containing products by at least one hour.
Calcium-channel blockers: (Minor) Monitor blood pressure during concurrent use of calcium and calcium-channel blockers. Concomitant use may reduce the response to calcium-channel blockers.
Candesartan; Hydrochlorothiazide, HCTZ: (Moderate) Monitor serum calcium concentration during concomitant calcium and thiazide diuretic use due to the risk for hypercalcemia. Thiazide diuretics may decrease urinary calcium excretion and cause intermittent and slight increases in serum calcium.
Captopril; Hydrochlorothiazide, HCTZ: (Moderate) Monitor serum calcium concentration during concomitant calcium and thiazide diuretic use due to the risk for hypercalcemia. Thiazide diuretics may decrease urinary calcium excretion and cause intermittent and slight increases in serum calcium.
Cardiac glycosides: (Moderate) Monitor for signs and symptoms of digoxin toxicity during concomitant calcium use. Hypercalcemia may predispose persons to digoxin toxicity. If IV calcium is administered rapidly in a person receiving digoxin, serious arrhythmias may occur. Monitor ECG and calcium concentrations closely during IV calcium and digoxin administration.
Ceftriaxone: (Major) Ceftriaxone is contraindicated in neonates who are receiving or are expected to receive IV calcium-containing solutions, including calcium-containing parenteral nutrition. Cases of fatal pulmonary and renal precipitate embolism in neonates have been described. There have been no reports of an interaction between ceftriaxone and oral calcium-containing products or between intramuscular ceftriaxone and calcium-containing products. Precipitation of ceftriaxone and calcium can occur when mixed. In patients other than neonates, the risk for precipitate embolism may be adequately addressed by separating administrations or administering each medication sequentially if IV infusion lines are thoroughly flushed between infusions with a compatible fluid.
Chlorothiazide: (Moderate) Monitor serum calcium concentration during concomitant calcium and thiazide diuretic use due to the risk for hypercalcemia. Thiazide diuretics may decrease urinary calcium excretion and cause intermittent and slight increases in serum calcium.
Chlorthalidone: (Moderate) Monitor serum calcium concentration during concomitant calcium and thiazide diuretic use due to the risk for hypercalcemia. Thiazide diuretics may decrease urinary calcium excretion and cause intermittent and slight increases in serum calcium.
Ciprofloxacin: (Moderate) Administer oral ciprofloxacin at least 2 hours before or 6 hours after oral products that contain calcium. Ciprofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Examples of compounds that may interfere with quinolone bioavailability include antacids and multivitamins that contain calcium.
Cisatracurium: (Moderate) Concomitant use of neuromuscular blockers and calcium may result in resistance to neuromuscular blockade. Calcium antagonizes the potentiating effect of magnesium on neuromuscular blockade. Also, calcium triggers acetylcholine release, and therefore, may both reduce the sensitivity to neuromuscular blockers and decrease the duration of neuromuscular blockade.
Clevidipine: (Minor) Monitor blood pressure during concurrent use of calcium and calcium-channel blockers. Concomitant use may reduce the response to calcium-channel blockers.
Cod Liver Oil: (Minor) Doses in excess of 1,500 to 2,000 mcg per day of Vitamin A may lead to bone loss and will counteract the effects of supplementation with calcium salts.
Conjugated Estrogens: (Minor) Estrogens can increase calcium absorption. Use caution in patients predisposed to hypercalcemia or nephrolithiasis.
Conjugated Estrogens; Bazedoxifene: (Minor) Estrogens can increase calcium absorption. Use caution in patients predisposed to hypercalcemia or nephrolithiasis.
Conjugated Estrogens; Medroxyprogesterone: (Minor) Estrogens can increase calcium absorption. Use caution in patients predisposed to hypercalcemia or nephrolithiasis.
Delafloxacin: (Major) Administer oral delafloxacin at least 2 hours before or 6 hours after oral products that contain calcium. Delafloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Examples of compounds that may interfere with fluoroquinolone bioavailability include antacids and multivitamins that contain calcium.
Demeclocycline: (Moderate) Divalent or trivalent cations readily chelate with tetracycline antibiotics, forming insoluble compounds. The oral absorption of these antibiotics will be significantly reduced by other orally administered compounds that contain calcium salts, particularly if the time of administration is within 60 minutes of each other. Calcium salts and tetracyclines should not be administered within 1 to 2 hours of each other, although doxycycline chelates less with calcium than other tetracyclines.
Desogestrel; Ethinyl Estradiol: (Minor) Estrogens can increase calcium absorption. Use caution in patients predisposed to hypercalcemia or nephrolithiasis.
Dienogest; Estradiol valerate: (Minor) Estrogens can increase calcium absorption. Use caution in patients predisposed to hypercalcemia or nephrolithiasis.
Digoxin: (Moderate) Monitor for signs and symptoms of digoxin toxicity during concomitant calcium use. Hypercalcemia may predispose persons to digoxin toxicity. If IV calcium is administered rapidly in a person receiving digoxin, serious arrhythmias may occur. Monitor ECG and calcium concentrations closely during IV calcium and digoxin administration.
Diltiazem: (Minor) Monitor blood pressure during concurrent use of calcium and calcium-channel blockers. Concomitant use may reduce the response to calcium-channel blockers.
Diphenhydramine; Naproxen: (Minor) Concomitant administration of antacids can delay the absorption of naproxen. Periodic antacid use should not be problematic as long as the antacid and enteric-coated naproxen administration are separated by at least 2 hours.
Dolutegravir: (Moderate) Administer dolutegravir 2 hours before or 6 hours after taking supplements containing calcium if given under fasting conditions. When taken with food, dolutegravir and supplements containing calcium can be taken at the same time. Simultaneous administration under fasted conditions may result in reduced bioavailability of dolutegravir.
Dolutegravir; Lamivudine: (Moderate) Administer dolutegravir 2 hours before or 6 hours after taking supplements containing calcium if given under fasting conditions. When taken with food, dolutegravir and supplements containing calcium can be taken at the same time. Simultaneous administration under fasted conditions may result in reduced bioavailability of dolutegravir.
Dolutegravir; Rilpivirine: (Moderate) Administer dolutegravir 2 hours before or 6 hours after taking supplements containing calcium if given under fasting conditions. When taken with food, dolutegravir and supplements containing calcium can be taken at the same time. Simultaneous administration under fasted conditions may result in reduced bioavailability of dolutegravir.
Doxercalciferol: (Moderate) Monitor serum calcium concentrations during concomitant use of high doses of calcium and vitamin D analogs; a dosage adjustment of the vitamin D analog may be needed. Hypercalcemia may be exacerbated by concomitant administration.
Doxycycline: (Moderate) Divalent or trivalent cations readily chelate with tetracycline antibiotics, forming insoluble compounds. The oral absorption of these antibiotics will be significantly reduced by other orally administered compounds that contain calcium salts, particularly if the time of administration is within 60 minutes of each other. Calcium salts and tetracyclines should not be administered within 1 to 2 hours of each other, although doxycycline chelates less with calcium than other tetracyclines.
Drospirenone; Estetrol: (Minor) Estrogens can increase calcium absorption. Use caution in patients predisposed to hypercalcemia or nephrolithiasis.
Drospirenone; Estradiol: (Minor) Estrogens can increase calcium absorption. Use caution in patients predisposed to hypercalcemia or nephrolithiasis.
Drospirenone; Ethinyl Estradiol: (Minor) Estrogens can increase calcium absorption. Use caution in patients predisposed to hypercalcemia or nephrolithiasis.
Drospirenone; Ethinyl Estradiol; Levomefolate: (Minor) Estrogens can increase calcium absorption. Use caution in patients predisposed to hypercalcemia or nephrolithiasis.
Edetate Calcium Disodium, Calcium EDTA: (Major) Because edetate disodium chelates and lowers serum calcium, oral or parenteral calcium salts should not be administered concomitantly.
Elagolix; Estradiol; Norethindrone acetate: (Minor) Estrogens can increase calcium absorption. Use caution in patients predisposed to hypercalcemia or nephrolithiasis.
Eltrombopag: (Major) Eltrombopag chelates polyvalent cations (e.g., calcium, aluminum, and magnesium) in food, mineral supplements, and antacids. In a clinical study, systemic exposure to eltrombopag was decreased by 70% when it was administered with a polyvalent cation-containing antacid. Administer eltrombopag at least 2 hours before or 4 hours after any oral products containing polyvalent cations, such as aluminum salts, (like aluminum hydroxide), calcium salts, (including calcium carbonate), and magnesium salts.
Enalapril; Hydrochlorothiazide, HCTZ: (Moderate) Monitor serum calcium concentration during concomitant calcium and thiazide diuretic use due to the risk for hypercalcemia. Thiazide diuretics may decrease urinary calcium excretion and cause intermittent and slight increases in serum calcium.
Eprosartan; Hydrochlorothiazide, HCTZ: (Moderate) Monitor serum calcium concentration during concomitant calcium and thiazide diuretic use due to the risk for hypercalcemia. Thiazide diuretics may decrease urinary calcium excretion and cause intermittent and slight increases in serum calcium.
Esterified Estrogens: (Minor) Estrogens can increase calcium absorption. Use caution in patients predisposed to hypercalcemia or nephrolithiasis.
Esterified Estrogens; Methyltestosterone: (Minor) Estrogens can increase calcium absorption. Use caution in patients predisposed to hypercalcemia or nephrolithiasis.
Estradiol: (Minor) Estrogens can increase calcium absorption. Use caution in patients predisposed to hypercalcemia or nephrolithiasis.
Estradiol; Levonorgestrel: (Minor) Estrogens can increase calcium absorption. Use caution in patients predisposed to hypercalcemia or nephrolithiasis.
Estradiol; Norethindrone: (Minor) Estrogens can increase calcium absorption. Use caution in patients predisposed to hypercalcemia or nephrolithiasis.
Estradiol; Norgestimate: (Minor) Estrogens can increase calcium absorption. Use caution in patients predisposed to hypercalcemia or nephrolithiasis.
Estradiol; Progesterone: (Minor) Estrogens can increase calcium absorption. Use caution in patients predisposed to hypercalcemia or nephrolithiasis.
Estramustine: (Major) Administration of estramustine with calcium impairs the oral absorption of estramustine significantly, due to formation of a calcium-phosphate complex. Calcium-containing drugs must not be taken simultaneously with estramustine. Patients should be instructed to take estramustine with water at least 1 hour before or 2 hours after calcium supplements.
Estrogens: (Minor) Estrogens can increase calcium absorption. Use caution in patients predisposed to hypercalcemia or nephrolithiasis.
Estropipate: (Minor) Estrogens can increase calcium absorption. Use caution in patients predisposed to hypercalcemia or nephrolithiasis.
Ethinyl Estradiol; Norelgestromin: (Minor) Estrogens can increase calcium absorption. Use caution in patients predisposed to hypercalcemia or nephrolithiasis.
Ethinyl Estradiol; Norethindrone Acetate: (Minor) Estrogens can increase calcium absorption. Use caution in patients predisposed to hypercalcemia or nephrolithiasis.
Ethinyl Estradiol; Norgestrel: (Minor) Estrogens can increase calcium absorption. Use caution in patients predisposed to hypercalcemia or nephrolithiasis.
Ethotoin: (Major) Oral absorption of phenytoin can be reduced by calcium salts. Calcium salts can form complexes that are nonabsorbable. Separating the administration of phenytoin and calcium salts by at least 2 hours to help avoid this interaction. A similar interaction may occur with ethotoin.
Ethynodiol Diacetate; Ethinyl Estradiol: (Minor) Estrogens can increase calcium absorption. Use caution in patients predisposed to hypercalcemia or nephrolithiasis.
Etonogestrel; Ethinyl Estradiol: (Minor) Estrogens can increase calcium absorption. Use caution in patients predisposed to hypercalcemia or nephrolithiasis.
Felodipine: (Minor) Monitor blood pressure during concurrent use of calcium and calcium-channel blockers. Concomitant use may reduce the response to calcium-channel blockers.
Fosinopril; Hydrochlorothiazide, HCTZ: (Moderate) Monitor serum calcium concentration during concomitant calcium and thiazide diuretic use due to the risk for hypercalcemia. Thiazide diuretics may decrease urinary calcium excretion and cause intermittent and slight increases in serum calcium.
Hydrochlorothiazide, HCTZ: (Moderate) Monitor serum calcium concentration during concomitant calcium and thiazide diuretic use due to the risk for hypercalcemia. Thiazide diuretics may decrease urinary calcium excretion and cause intermittent and slight increases in serum calcium.
Hydrochlorothiazide, HCTZ; Moexipril: (Moderate) Monitor serum calcium concentration during concomitant calcium and thiazide diuretic use due to the risk for hypercalcemia. Thiazide diuretics may decrease urinary calcium excretion and cause intermittent and slight increases in serum calcium.
Ibritumomab Tiuxetan: (Moderate) The oral absorption of phosphorus is reduced by ingestion of pharmacologic doses of calcium carbonate or other phosphate-lowering calcium salts (e.g., calcium acetate). There is, however, no significant interference with phosphorus absorption by oral dietary calcium at intakes within the typical adult range. If the patient requires multiple calcium supplements or a calcium-containing antacid, it may be wise to separate the administration of phosphorus salts from calcium-containing products. In some instances the administration of calcium salts or calcium carbonate is used therapeutically (e.g., uremia) to decrease serum phosphorus levels, so the administration of phosphorus supplements would dynamically counteract the intended use of calcium in these settings, assuming hypophosphatemia is not present. Appropriate calcium-phosphorus ratios in vivo are important for proper calcium homeostasis in tissues and bone; if the serum ionized calcium concentration is elevated, the concomitant use of calcium salts and phosphorus salts may increase the risk of calcium deposition in soft tissue.
Irbesartan; Hydrochlorothiazide, HCTZ: (Moderate) Monitor serum calcium concentration during concomitant calcium and thiazide diuretic use due to the risk for hypercalcemia. Thiazide diuretics may decrease urinary calcium excretion and cause intermittent and slight increases in serum calcium.
Isradipine: (Minor) Monitor blood pressure during concurrent use of calcium and calcium-channel blockers. Concomitant use may reduce the response to calcium-channel blockers.
Levamlodipine: (Minor) Monitor blood pressure during concurrent use of calcium and calcium-channel blockers. Concomitant use may reduce the response to calcium-channel blockers.
Levofloxacin: (Moderate) Administer oral products that contain calcium at least 2 hours before or 2 hours after orally administered levofloxacin. Levofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Chelation of divalent cations with levofloxacin is less than with other quinolones. Examples of compounds that may interfere with quinolone bioavailability include antacids and multivitamins that contain calcium.
Levonorgestrel; Ethinyl Estradiol: (Minor) Estrogens can increase calcium absorption. Use caution in patients predisposed to hypercalcemia or nephrolithiasis.
Levonorgestrel; Ethinyl Estradiol; Ferrous Bisglycinate: (Minor) Estrogens can increase calcium absorption. Use caution in patients predisposed to hypercalcemia or nephrolithiasis.
Levonorgestrel; Ethinyl Estradiol; Ferrous Fumarate: (Minor) Estrogens can increase calcium absorption. Use caution in patients predisposed to hypercalcemia or nephrolithiasis.
Levothyroxine: (Moderate) Thyroid hormones should be administered at least 4 hours before or after the ingestion of oral calcium supplements. Calcium salts have been reported to chelate oral thyroid hormones within the GI tract when administered simultaneously, leading to decreased thyroid hormone absorption. Some case reports have described clinical hypothyroidism resulting from coadministration of thyroid hormones with oral calcium supplements.
Levothyroxine; Liothyronine (Porcine): (Moderate) Thyroid hormones should be administered at least 4 hours before or after the ingestion of oral calcium supplements. Calcium salts have been reported to chelate oral thyroid hormones within the GI tract when administered simultaneously, leading to decreased thyroid hormone absorption. Some case reports have described clinical hypothyroidism resulting from coadministration of thyroid hormones with oral calcium supplements.
Levothyroxine; Liothyronine (Synthetic): (Moderate) Thyroid hormones should be administered at least 4 hours before or after the ingestion of oral calcium supplements. Calcium salts have been reported to chelate oral thyroid hormones within the GI tract when administered simultaneously, leading to decreased thyroid hormone absorption. Some case reports have described clinical hypothyroidism resulting from coadministration of thyroid hormones with oral calcium supplements.
Liothyronine: (Moderate) Thyroid hormones should be administered at least 4 hours before or after the ingestion of oral calcium supplements. Calcium salts have been reported to chelate oral thyroid hormones within the GI tract when administered simultaneously, leading to decreased thyroid hormone absorption. Some case reports have described clinical hypothyroidism resulting from coadministration of thyroid hormones with oral calcium supplements.
Lisinopril; Hydrochlorothiazide, HCTZ: (Moderate) Monitor serum calcium concentration during concomitant calcium and thiazide diuretic use due to the risk for hypercalcemia. Thiazide diuretics may decrease urinary calcium excretion and cause intermittent and slight increases in serum calcium.
Lithium: (Moderate) Monitor serum calcium concentrations closely if concomitant use of calcium and lithium is necessary. Concomitant use may increase the risk of hypercalcemia.
Losartan; Hydrochlorothiazide, HCTZ: (Moderate) Monitor serum calcium concentration during concomitant calcium and thiazide diuretic use due to the risk for hypercalcemia. Thiazide diuretics may decrease urinary calcium excretion and cause intermittent and slight increases in serum calcium.
Metolazone: (Moderate) Monitor serum calcium concentration during concomitant calcium and thiazide diuretic use due to the risk for hypercalcemia. Thiazide diuretics may decrease urinary calcium excretion and cause intermittent and slight increases in serum calcium.
Metoprolol; Hydrochlorothiazide, HCTZ: (Moderate) Monitor serum calcium concentration during concomitant calcium and thiazide diuretic use due to the risk for hypercalcemia. Thiazide diuretics may decrease urinary calcium excretion and cause intermittent and slight increases in serum calcium.
Minocycline: (Moderate) Divalent or trivalent cations readily chelate with tetracycline antibiotics, forming insoluble compounds. The oral absorption of these antibiotics will be significantly reduced by other orally administered compounds that contain calcium salts, particularly if the time of administration is within 60 minutes of each other. Calcium salts and tetracyclines should not be administered within 1 to 2 hours of each other, although doxycycline chelates less with calcium than other tetracyclines.
Moxifloxacin: (Major) Administer oral moxifloxacin at least 4 hours before or 8 hours after oral products that contain calcium. Moxifloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Examples of compounds that may interfere with quinolone bioavailability include antacids and multivitamins that contain calcium.
Naproxen: (Minor) Concomitant administration of antacids can delay the absorption of naproxen. Periodic antacid use should not be problematic as long as the antacid and enteric-coated naproxen administration are separated by at least 2 hours.
Naproxen; Esomeprazole: (Minor) Concomitant administration of antacids can delay the absorption of naproxen. Periodic antacid use should not be problematic as long as the antacid and enteric-coated naproxen administration are separated by at least 2 hours.
Naproxen; Pseudoephedrine: (Minor) Concomitant administration of antacids can delay the absorption of naproxen. Periodic antacid use should not be problematic as long as the antacid and enteric-coated naproxen administration are separated by at least 2 hours.
Neuromuscular blockers: (Moderate) Concomitant use of neuromuscular blockers and calcium may result in resistance to neuromuscular blockade. Calcium antagonizes the potentiating effect of magnesium on neuromuscular blockade. Also, calcium triggers acetylcholine release, and therefore, may both reduce the sensitivity to neuromuscular blockers and decrease the duration of neuromuscular blockade.
Nicardipine: (Minor) Monitor blood pressure during concurrent use of calcium and calcium-channel blockers. Concomitant use may reduce the response to calcium-channel blockers.
NIFEdipine: (Minor) Monitor blood pressure during concurrent use of calcium and calcium-channel blockers. Concomitant use may reduce the response to calcium-channel blockers.
Nimodipine: (Minor) Monitor blood pressure during concurrent use of calcium and calcium-channel blockers. Concomitant use may reduce the response to calcium-channel blockers.
Nisoldipine: (Minor) Monitor blood pressure during concurrent use of calcium and calcium-channel blockers. Concomitant use may reduce the response to calcium-channel blockers.
Norethindrone Acetate; Ethinyl Estradiol; Ferrous fumarate: (Minor) Estrogens can increase calcium absorption. Use caution in patients predisposed to hypercalcemia or nephrolithiasis.
Norethindrone; Ethinyl Estradiol: (Minor) Estrogens can increase calcium absorption. Use caution in patients predisposed to hypercalcemia or nephrolithiasis.
Norethindrone; Ethinyl Estradiol; Ferrous fumarate: (Minor) Estrogens can increase calcium absorption. Use caution in patients predisposed to hypercalcemia or nephrolithiasis.
Norgestimate; Ethinyl Estradiol: (Minor) Estrogens can increase calcium absorption. Use caution in patients predisposed to hypercalcemia or nephrolithiasis.
Ofloxacin: (Moderate) Administer oral products that contain calcium at least 2 hours before or 2 hours after ofloxacin. Ofloxacin absorption may be reduced as quinolone antibiotics can chelate with divalent or trivalent cations. Examples of compounds that may interfere with quinolone bioavailability include antacids and multivitamins that contain calcium.
Olmesartan; Amlodipine; Hydrochlorothiazide, HCTZ: (Moderate) Monitor serum calcium concentration during concomitant calcium and thiazide diuretic use due to the risk for hypercalcemia. Thiazide diuretics may decrease urinary calcium excretion and cause intermittent and slight increases in serum calcium. (Minor) Monitor blood pressure during concurrent use of calcium and calcium-channel blockers. Concomitant use may reduce the response to calcium-channel blockers.
Olmesartan; Hydrochlorothiazide, HCTZ: (Moderate) Monitor serum calcium concentration during concomitant calcium and thiazide diuretic use due to the risk for hypercalcemia. Thiazide diuretics may decrease urinary calcium excretion and cause intermittent and slight increases in serum calcium.
Omadacycline: (Moderate) Divalent or trivalent cations readily chelate with tetracycline antibiotics, forming insoluble compounds. The oral absorption of these antibiotics will be significantly reduced by other orally administered compounds that contain calcium salts, particularly if the time of administration is within 60 minutes of each other. Calcium salts and tetracyclines should not be administered within 1 to 2 hours of each other, although doxycycline chelates less with calcium than other tetracyclines.
Pancuronium: (Moderate) Concomitant use of neuromuscular blockers and calcium may result in resistance to neuromuscular blockade. Calcium antagonizes the potentiating effect of magnesium on neuromuscular blockade. Also, calcium triggers acetylcholine release, and therefore, may both reduce the sensitivity to neuromuscular blockers and decrease the duration of neuromuscular blockade.
Parathyroid Hormone: (Moderate) Monitor serum calcium concentrations closely if concomitant use of calcium and parathyroid hormone is necessary. Concomitant use may increase the risk of hypercalcemia.
Paricalcitol: (Moderate) Monitor serum calcium concentrations during concomitant use of high doses of calcium and vitamin D analogs; a dosage adjustment of the vitamin D analog may be needed. Hypercalcemia may be exacerbated by concomitant administration.
Perindopril; Amlodipine: (Minor) Monitor blood pressure during concurrent use of calcium and calcium-channel blockers. Concomitant use may reduce the response to calcium-channel blockers.
Phenytoin: (Moderate) Oral absorption of phenytoin can be reduced by calcium salts. Calcium salts can form complexes that are nonabsorbable. Separating the administration of phenytoin and calcium salts by at least 2 hours will help avoid this interaction.
Phosphorated Carbohydrate Solution: (Moderate) The oral absorption of phosphorus is reduced by ingestion of pharmacologic doses of calcium carbonate or other phosphate-lowering calcium salts (e.g., calcium acetate). There is, however, no significant interference with phosphorus absorption by oral dietary calcium at intakes within the typical adult range. If the patient requires multiple calcium supplements or a calcium-containing antacid, it may be wise to separate the administration of phosphorus salts from calcium-containing products. In some instances the administration of calcium salts or calcium carbonate is used therapeutically (e.g., uremia) to decrease serum phosphorus levels, so the administration of phosphorus supplements would dynamically counteract the intended use of calcium in these settings, assuming hypophosphatemia is not present. Appropriate calcium-phosphorus ratios in vivo are important for proper calcium homeostasis in tissues and bone; if the serum ionized calcium concentration is elevated, the concomitant use of calcium salts and phosphorus salts may increase the risk of calcium deposition in soft tissue.
Phosphorus: (Moderate) The oral absorption of phosphorus is reduced by ingestion of pharmacologic doses of calcium carbonate or other phosphate-lowering calcium salts (e.g., calcium acetate). There is, however, no significant interference with phosphorus absorption by oral dietary calcium at intakes within the typical adult range. If the patient requires multiple calcium supplements or a calcium-containing antacid, it may be wise to separate the administration of phosphorus salts from calcium-containing products. In some instances the administration of calcium salts or calcium carbonate is used therapeutically (e.g., uremia) to decrease serum phosphorus levels, so the administration of phosphorus supplements would dynamically counteract the intended use of calcium in these settings, assuming hypophosphatemia is not present. Appropriate calcium-phosphorus ratios in vivo are important for proper calcium homeostasis in tissues and bone; if the serum ionized calcium concentration is elevated, the concomitant use of calcium salts and phosphorus salts may increase the risk of calcium deposition in soft tissue.
Potassium Phosphate: (Moderate) The oral absorption of phosphorus is reduced by ingestion of pharmacologic doses of calcium carbonate or other phosphate-lowering calcium salts (e.g., calcium acetate). There is, however, no significant interference with phosphorus absorption by oral dietary calcium at intakes within the typical adult range. If the patient requires multiple calcium supplements or a calcium-containing antacid, it may be wise to separate the administration of phosphorus salts from calcium-containing products. In some instances the administration of calcium salts or calcium carbonate is used therapeutically (e.g., uremia) to decrease serum phosphorus levels, so the administration of phosphorus supplements would dynamically counteract the intended use of calcium in these settings, assuming hypophosphatemia is not present. Appropriate calcium-phosphorus ratios in vivo are important for proper calcium homeostasis in tissues and bone; if the serum ionized calcium concentration is elevated, the concomitant use of calcium salts and phosphorus salts may increase the risk of calcium deposition in soft tissue.
Potassium Phosphate; Sodium Phosphate: (Moderate) The oral absorption of phosphorus is reduced by ingestion of pharmacologic doses of calcium carbonate or other phosphate-lowering calcium salts (e.g., calcium acetate). There is, however, no significant interference with phosphorus absorption by oral dietary calcium at intakes within the typical adult range. If the patient requires multiple calcium supplements or a calcium-containing antacid, it may be wise to separate the administration of phosphorus salts from calcium-containing products. In some instances the administration of calcium salts or calcium carbonate is used therapeutically (e.g., uremia) to decrease serum phosphorus levels, so the administration of phosphorus supplements would dynamically counteract the intended use of calcium in these settings, assuming hypophosphatemia is not present. Appropriate calcium-phosphorus ratios in vivo are important for proper calcium homeostasis in tissues and bone; if the serum ionized calcium concentration is elevated, the concomitant use of calcium salts and phosphorus salts may increase the risk of calcium deposition in soft tissue.
Quinapril; Hydrochlorothiazide, HCTZ: (Moderate) Monitor serum calcium concentration during concomitant calcium and thiazide diuretic use due to the risk for hypercalcemia. Thiazide diuretics may decrease urinary calcium excretion and cause intermittent and slight increases in serum calcium.
Relugolix; Estradiol; Norethindrone acetate: (Minor) Estrogens can increase calcium absorption. Use caution in patients predisposed to hypercalcemia or nephrolithiasis.
Rocuronium: (Moderate) Concomitant use of neuromuscular blockers and calcium may result in resistance to neuromuscular blockade. Calcium antagonizes the potentiating effect of magnesium on neuromuscular blockade. Also, calcium triggers acetylcholine release, and therefore, may both reduce the sensitivity to neuromuscular blockers and decrease the duration of neuromuscular blockade.
Sarecycline: (Moderate) Divalent or trivalent cations readily chelate with tetracycline antibiotics, forming insoluble compounds. The oral absorption of these antibiotics will be significantly reduced by other orally administered compounds that contain calcium salts, particularly if the time of administration is within 60 minutes of each other. Calcium salts and tetracyclines should not be administered within 1 to 2 hours of each other, although doxycycline chelates less with calcium than other tetracyclines.
Segesterone Acetate; Ethinyl Estradiol: (Minor) Estrogens can increase calcium absorption. Use caution in patients predisposed to hypercalcemia or nephrolithiasis.
Sodium Fluoride: (Moderate) Absorption of sodium fluoride may be reduced by concomitant use of antacids that contain magnesium, aluminum, or calcium. An interval of at least 2 hours is advisable between administration of sodium fluoride and antacids.
Sodium Phosphate Monobasic Monohydrate; Sodium Phosphate Dibasic Anhydrous: (Moderate) The concomitant use of oral sodium phosphate monobasic monohydrate; sodium phosphate dibasic anhydrous preparations in conjunction with antacids containing calcium (e.g., calcium carbonate, calcium salts) may bind the phosphate in the stomach and reduce its absorption. If the patient requires multiple mineral supplements or concurrent use of antacids, it is prudent to separate the administration of sodium phosphate salts from calcium containing products by at least one hour.
Spironolactone; Hydrochlorothiazide, HCTZ: (Moderate) Monitor serum calcium concentration during concomitant calcium and thiazide diuretic use due to the risk for hypercalcemia. Thiazide diuretics may decrease urinary calcium excretion and cause intermittent and slight increases in serum calcium.
Succinylcholine: (Moderate) Concomitant use of neuromuscular blockers and calcium may result in resistance to neuromuscular blockade. Calcium antagonizes the potentiating effect of magnesium on neuromuscular blockade. Also, calcium triggers acetylcholine release, and therefore, may both reduce the sensitivity to neuromuscular blockers and decrease the duration of neuromuscular blockade.
Sucralfate: (Moderate) Calcium salts potentially interfere with gastric mucosal binding of sucralfate. This interaction can be minimized by staggering the doses of these agents as much as possible.
Sulfacetamide; Sulfur: (Major) Because edetate disodium chelates and lowers serum calcium, oral or parenteral calcium salts should not be administered concomitantly.
Sumatriptan; Naproxen: (Minor) Concomitant administration of antacids can delay the absorption of naproxen. Periodic antacid use should not be problematic as long as the antacid and enteric-coated naproxen administration are separated by at least 2 hours.
Telmisartan; Amlodipine: (Minor) Monitor blood pressure during concurrent use of calcium and calcium-channel blockers. Concomitant use may reduce the response to calcium-channel blockers.
Telmisartan; Hydrochlorothiazide, HCTZ: (Moderate) Monitor serum calcium concentration during concomitant calcium and thiazide diuretic use due to the risk for hypercalcemia. Thiazide diuretics may decrease urinary calcium excretion and cause intermittent and slight increases in serum calcium.
Teriparatide: (Moderate) Monitor serum calcium concentrations closely if concomitant use of calcium and teriparatide is necessary. Concomitant use may increase the risk of hypercalcemia.
Tetracycline: (Moderate) Divalent or trivalent cations readily chelate with tetracycline antibiotics, forming insoluble compounds. The oral absorption of these antibiotics will be significantly reduced by other orally administered compounds that contain calcium salts, particularly if the time of administration is within 60 minutes of each other. Calcium salts and tetracyclines should not be administered within 1 to 2 hours of each other, although doxycycline chelates less with calcium than other tetracyclines.
Tetracyclines: (Moderate) Divalent or trivalent cations readily chelate with tetracycline antibiotics, forming insoluble compounds. The oral absorption of these antibiotics will be significantly reduced by other orally administered compounds that contain calcium salts, particularly if the time of administration is within 60 minutes of each other. Calcium salts and tetracyclines should not be administered within 1 to 2 hours of each other, although doxycycline chelates less with calcium than other tetracyclines.
Thiazide diuretics: (Moderate) Monitor serum calcium concentration during concomitant calcium and thiazide diuretic use due to the risk for hypercalcemia. Thiazide diuretics may decrease urinary calcium excretion and cause intermittent and slight increases in serum calcium.
Thyroid hormones: (Moderate) Thyroid hormones should be administered at least 4 hours before or after the ingestion of oral calcium supplements. Calcium salts have been reported to chelate oral thyroid hormones within the GI tract when administered simultaneously, leading to decreased thyroid hormone absorption. Some case reports have described clinical hypothyroidism resulting from coadministration of thyroid hormones with oral calcium supplements.
Trandolapril; Verapamil: (Minor) Monitor blood pressure during concurrent use of calcium and calcium-channel blockers. Concomitant use may reduce the response to calcium-channel blockers.
Triamterene; Hydrochlorothiazide, HCTZ: (Moderate) Monitor serum calcium concentration during concomitant calcium and thiazide diuretic use due to the risk for hypercalcemia. Thiazide diuretics may decrease urinary calcium excretion and cause intermittent and slight increases in serum calcium.
Trientine: (Major) In general, oral mineral supplements should not be given since they may block the oral absorption of trientine. However, iron deficiency may develop, especially in children and menstruating or pregnant women, or as a result of the low copper diet recommended for Wilson's disease. If necessary, iron may be given in short courses, but since iron and trientine each inhibit oral absorption of the other, 2 hours should elapse between administration of trientine and iron doses.
Valsartan; Hydrochlorothiazide, HCTZ: (Moderate) Monitor serum calcium concentration during concomitant calcium and thiazide diuretic use due to the risk for hypercalcemia. Thiazide diuretics may decrease urinary calcium excretion and cause intermittent and slight increases in serum calcium.
Vecuronium: (Moderate) Concomitant use of neuromuscular blockers and calcium may result in resistance to neuromuscular blockade. Calcium antagonizes the potentiating effect of magnesium on neuromuscular blockade. Also, calcium triggers acetylcholine release, and therefore, may both reduce the sensitivity to neuromuscular blockers and decrease the duration of neuromuscular blockade.
Verapamil: (Minor) Monitor blood pressure during concurrent use of calcium and calcium-channel blockers. Concomitant use may reduce the response to calcium-channel blockers.
Vitamin A: (Minor) Doses in excess of 1,500 to 2,000 mcg per day of Vitamin A may lead to bone loss and will counteract the effects of supplementation with calcium salts.
Vitamin D analogs: (Moderate) Monitor serum calcium concentrations during concomitant use of high doses of calcium and vitamin D analogs; a dosage adjustment of the vitamin D analog may be needed. Hypercalcemia may be exacerbated by concomitant administration.
Calcium is the primary component of skeletal tissue, providing structural integrity and support for individual growth. Bone undergoes constant remodeling and turnover. Mineral release during the process of bone resorption buffers hydrogen ions, whereas the formation of bone generates hydrogen ions. Thus, bone serves as a calcium depot and as a reservoir for electrolytes and buffers. Inhibition of bone resorption is primarily the function of the hormone, calcitonin. The control of plasma calcium concentration is primarily maintained by parathyroid hormone, thyroxine, and 1,25 dihydroxycholecalciferol. Ionized calcium is the physiologically active form. Basic metabolic functions involve the cardiac, neuromuscular, structural, and blood coagulation systems.
Calcium chloride is administered intravenously and intraosseously*. Calcium is required by all body tissues. Approximately 98% of the body's calcium is stored in the bone, primarily as the hydroxyapatite. Constant bone remodeling and turnover of the skeleton release calcium into the systemic circulation which is then re-accumulated by the bone on a daily basis. Calcium is 40% bound to plasma proteins, primarily albumin, and 10% is in a chelated form. Approximately 50% of serum calcium is ionized, which is considered the physiologically active form. The ultrafiltratable calcium (nonprotein-bound) is distributed to the protein-poor regions of the body, such as the cerebrospinal and extracellular fluids. Calcium is primarily excreted in the feces and bile (80%). Urinary excretion accounts for the remainder (20%). However, approximately 99% of filtered calcium is reabsorbed by the kidney with less than 1% excreted. Parathyroid hormone, calcitonin, and 1,25 dihydroxycholecalciferol are primarily responsible for controlling calcium equilibrium. Insulin, thyroxine, growth hormone, androgens, estrogens, adrenal corticosteroids, and inorganic phosphate also contribute.
Affected cytochrome P450 isoenzymes: none
-Route-Specific Pharmacokinetics
Intravenous Route
Calcium chloride is more bioavailable than calcium gluconate and results in greater increases in serum ionized calcium concentrations than does calcium gluconate.