From the Guidelines
The recommended dose of Imitrex (sumatriptan) for subcutaneous (SC) or intramuscular (IM) injection is 6 mg, with a maximum recommended dose of 12 mg in a 24-hour period. This dosage is based on the study published in the American Family Physician in 2002 1, which provides guidance on the management of acute migraine headaches. According to the study, sumatriptan is available in subcutaneous or intranasal form, and the subcutaneous form reaches peak blood concentrations faster than any other migraine-specific medications, in approximately 15 minutes.
Key Points to Consider
- The dose of 6 mg is effective in 70 to 82 percent of patients, as reported in the study 1.
- The medication should be administered via subcutaneous or intramuscular injection, with the option to use a pre-filled autoinjector or syringe.
- Patients should be advised of common side effects, including injection site reactions, flushing, chest tightness, and dizziness.
- Imitrex is contraindicated in patients with coronary artery disease, uncontrolled hypertension, hemiplegic or basilar migraine, and within 24 hours of using other triptans or ergot-containing medications, as stated in the study 1.
Administration and Onset of Action
- The medication works by stimulating serotonin receptors, causing vasoconstriction of dilated cerebral blood vessels and inhibiting the release of inflammatory neuropeptides involved in migraine pathophysiology.
- The onset of action is typically within 10-15 minutes for the injectable form, making it particularly useful for rapidly progressing migraines, as noted in the study 1.
From the FDA Drug Label
The maximum single recommended adult dose of IMITREX Injection is 6 mg injected subcutaneously. If side effects are dose limiting, then lower doses may be used The maximum recommended dose that may be given in 24 hours is two 6-mg injections separated by at least 1 hour
The dose of SC or IM Imitrex is 6 mg.
- The maximum recommended dose in 24 hours is two 6-mg injections separated by at least 1 hour.
- Lower doses may be used if side effects are dose limiting 2
From the Research
Dose of SC or IM Imitrex
- The recommended dosage of sumatriptan at the onset of migraine symptoms is 100 mg orally or 6 mg subcutaneously 3.
- Subcutaneous doses of 6 to 8 mg have been shown to reduce migraine headache from 'moderate or severe' to 'mild or none' within 1 hour in 70 to 80% of patients 4.
- The dose of sumatriptan for cluster headache is 6 mg subcutaneously 3.
- There is no mention of an intramuscular (IM) dose of imitrex in the provided studies, only subcutaneous (SC) and oral doses.
- It is worth noting that sumatriptan should not be given together with vasoconstrictive substances, e.g., ergotamines, or with migraine prophylactics with similar properties, e.g., methysergide 3.
- Sumatriptan should not be given during the migraine aura and is contraindicated in patients with ischaemic heart disease, previous myocardial infarction, Prinzmetal (variant) angina and uncontrolled hypertension 3.