Methyl salicylate is a topical analgesic indicated for the temporary relief of minor aches and pains of muscles and joints, such as simple backache, lumbago, arthritis, neuralgia, strains, bruises, and sprains. It is also known as wintergreen oil or sweet birch oil. Historically, methyl salicylate was extracted from the wintergreen plant (Gaultheria procumbens) and birch trees (Betula lenta). Although prolonged use of methyl salicylate may cause dermatitis, methyl salicylate is generally safe in topical formulations.
General Administration Information
For storage information, see the specific product information within the How Supplied section.
Route-Specific Administration
Topical Administration
Cream/Ointment/Lotion Formulations
-Avoid contact with the eyes.
-Do not apply to wounds or damaged skin.
-Do not use in large quantities, particularly over raw surfaces or blistered areas.
-May be applied under occlusive dressing. Do not bandage.
Transdermal Patch Formulations
-Do not apply to wounds, cuts, damaged or infected skin.
-Do not apply on any mucous membranes, including eyes, mouth, or genitals.
-Do not apply heat to the treated area immediately before or after use.
-Clean and dry the affected area. Apply directly to affected area immediately after removal from the protective envelope. Do not leave the patch on for more than 8 hours.
-Wash hands after handling the patch. Fold the sticky side of used patches together, and dispose of in such a way as to prevent accidental exposure to children or pets.
-May be applied under occlusive dressing. Do not bandage.
-Discontinue use at least 1 hour prior to bath, shower, or swimming; do not use immediately after bath, shower, or swimming.
Local skin necrosis has been reported after the use of methyl salicylate and menthol along with periodic heating of the application area with a heating pad. Tinnitus, diplopia, dyspnea, mixed metabolic acidosis and respiratory alkalosis were also noted. A burning sensation may occur in the treatment area during use of the topical patch. The intensity of this reaction varies among individuals and may be severe. With regular use, this sensation generally disappears after several days.
Prolonged use of methyl salicylate may cause contact dermatitis.
NSAIDs, including methyl salicylate, may cause GI bleeding. Discontinue methyl salicylate use and evaluate any patients with worsening or persistent stomach pain or upset or feeling faint with bloody or black tarry stools or vomit.
Do not use methyl salicylate in patients with salicylate hypersensitivity or NSAID hypersensitivity.
Methyl salicylate is for external use only. It is not for ophthalmic administration; avoid ocular exposure. Do not apply the topical patch to mucous membranes, including the mouth and genitals. Do not use large quantities of the topical cream, particularly over raw surfaces or blistered areas. Do not bandage skin after methyl salicylate cream application; the methyl salicylate patch may be applied under an occlusive dressing. Do not apply methyl salicylate to a skin abrasion, wounds, cuts, or skin that is infected or damaged. Advise patients using the topical patch to avoid the application of heat, including the use of a heating pad, over the area of product application immediately before or after use.
NSAIDs, including methyl salicylate, cause serious gastrointestinal (GI) adverse events including inflammation, bleeding, ulceration, and GI perforation of the esophagus, stomach, small intestine, or large intestine, which can be fatal. These serious adverse events can occur at any time, with or without warning symptoms, in patients treated with NSAIDs. Patients with a prior history of peptic ulcer disease and/or GI bleeding who use NSAIDs have a more than 10-fold increased risk for developing a GI bleed compared to patients without risk factors. Other factors that increase the risk of GI bleeding in patients treated with NSAIDs include longer duration of NSAID therapy, concomitant oral corticosteroid therapy, anticoagulant therapy, aspirin, or selective serotonin reuptake inhibitors (SSRIs), tobacco smoking, ethanol ingestion, geriatric age, and poor general health status. Most postmarketing reports of fatal GI events occurred in elderly or debilitated patients. Additionally, patients with advanced liver disease or coagulopathy are at increased risk for GI bleeding. To minimize GI risks in NSAID-treated patients, use the lowest effective dosage for the shortest possible duration, and avoid administration of more than 1 NSAID at a time. In the setting of concomitant low-dose aspirin use for cardiac prophylaxis, monitor patients more closely for evidence of GI bleeding. Avoid NSAID use in higher risk populations unless the benefits are expected to outweigh the risks of bleeding; consider alternate therapy other than NSAIDs in higher risk patients as well as those with active GI bleeding. Remain alert for signs and symptoms of GI ulceration and bleeding during NSAID therapy.
Do not use methyl salicylate right before or after heart surgery, including coronary artery bypass graft surgery (CABG). Use methyl salicylate with caution in patients with hypertension or cardiac disease. The risk of heart attack or stroke may increase if methyl salicylate is used at higher doses or for longer durations.
Use methyl salicylate with caution in patients with renal disease.
Because some transdermal systems (i.e., patches) contain aluminum or other metal components, advise patients to remove the methyl salicylate topical patch before undergoing magnetic resonance imaging (MRI). Metal components contained in the backing of some transdermal systems can overheat during an MRI scan and cause skin burns in the area where the patch is adhered.
Do not use methyl salicylate during the last 3 months of pregnancy because it may cause problems in the unborn child or complications during delivery. There is no conclusive evidence that methyl salicylate is teratogenic in humans during pregnancy. In animal studies, central nervous system teratogenicity, alteration in renal pelvis and urine formation, and increased litter size have been reported. Topical application of methyl salicylate did not cause congenital defects when used at doses up to 6,000 mg/kg/day. The methyl salicylate doses in these studies were significantly higher than the adult lethal human dose on mg/kg basis.
Previous American Academy of Pediatrics recommendations suggest salicylates be used with caution during breast-feeding.
For the treatment of minor musculoskeletal pain, such as backache, lumbago, arthritis, neuralgia, strains, bruises, and sprains:
Topical dosage (methyl salicylate 25% cream):
Adults: Apply topically to affected area 1 to 4 times daily as needed. Discontinue use if condition worsens or does not improve within 7 days.
Children and Adolescents 2 to 17 years: Apply topically to affected area 1 to 4 times daily as needed. Discontinue use if condition worsens or does not improve within 7 days.
Topical dosage (methyl salicylate 10% patch):
Adults: Apply 1 patch topically to the affected area 1 to 3 times daily as needed. Do not leave the patch on for more than 8 hours. Discontinue use if condition worsens or does not improve within 7 days.
Maximum Dosage Limits:
-Adults
4 applications/day of the topical cream; 3 applications/day of the topical patch.
-Geriatric
4 applications/day of the topical cream; 3 applications/day of the topical patch.
-Adolescents
4 applications/day of the topical cream; safety and efficacy of the topical patch have not been established.
-Children
Children 2 to 12 years: 4 applications/day of the topical cream; safety and efficacy of the topical patch have not been established.
Children 1 year: Safety and efficacy have not been established.
-Infants
Safety and efficacy have not been established.
-Neonates
Safety and efficacy have not been established.
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
Specific guidelines for dosage adjustments in renal impairment are not available; it appears that no dosage adjustments are needed.
*non-FDA-approved indication
There are no drug interactions associated with Methyl Salicylate products.
Methyl salicylate is a topical salicylate analgesic, with anti-inflammatory and rubefacient/counterirritant properties. It is lipophilic, and when applied topically, it readily penetrates the skin and is hydrolyzed to salicylic acid in the tissues. Once absorbed, the salicylate distributes throughout the tissue and transcellular fluids, primarily through passive pH-dependent processes. It also has a vasodilatory action upon absorption resulting in an increased localised blood flow and a rise in tissue temperature, its rubefacient action.
Methyl salicylate is applied topically to the skin. It is lipophilic, and when applied topically, it readily penetrates the skin and is hydrolyzed to salicylic acid in the tissues. Once absorbed, the salicylate distributes throughout the tissue and transcellular fluids, primarily through passive pH-dependent processes. Conjugation with glycine to from salicyluric acid and with glucuronic acid to form salicyl acyl and phenolic glucuronide are the major metabolic pathways. The metabolites are excreted in the urine with free salicylate accounting for 10% to 30%. The estimated plasma half-life for salicylate is 2 to 3 hours in low doses and 12 hours at anti-inflammatory doses.
Affected cytochrome P450 isoenzymes and drug transporters: none