What is the dose of sumatriptan (Imitrex) for migraine treatment?

Sumatriptan Dosing for Migraine Treatment

For oral sumatriptan, start with 50 mg or 100 mg at migraine onset, as these doses provide superior efficacy compared to 25 mg, with a maximum daily dose of 200 mg in 24 hours; for subcutaneous administration, use 6 mg (repeatable after 1 hour, maximum 12 mg/24 hours); and for intranasal use, administer 5-10 mg (repeatable after 2 hours, maximum 40 mg/day). 1, 2

Oral Dosing Algorithm

Starting dose selection:

• The FDA-approved oral doses are 25 mg, 50 mg, or 100 mg, with 50 mg and 100 mg providing greater efficacy than 25 mg 1
• The 100 mg dose may not provide significantly greater effect than 50 mg but carries higher risk of adverse reactions 1
• The 50 mg dose offers the optimal efficacy-to-tolerability ratio, though many patients prefer or require 100 mg 3

Repeat dosing:

• If migraine has not resolved by 2 hours or returns after transient improvement, administer a second dose at least 2 hours after the first dose 1
• Maximum daily dose is 200 mg in a 24-hour period 1

Alternative Routes of Administration

Subcutaneous administration:

• Dose: 6 mg, repeatable after 1 hour 2, 4
• Maximum daily dose: 12 mg per 24 hours 2, 4
• Provides fastest relief (70-80% of patients experience relief within 1-2 hours) 5
• Common pitfall: Injection site reactions occur in approximately 30% of patients 2, 4

Intranasal administration:

• Dose: 5-10 mg (one to two sprays in one nostril), repeatable after 2 hours 2, 4
• Maximum daily dose: 40 mg per day 2

Special Populations

Hepatic impairment:

• Maximum single dose should not exceed 50 mg in patients with mild to moderate hepatic impairment 1

Treatment Optimization Strategy

Trial period:

• Patients should try sumatriptan for 2-3 headache episodes before determining effectiveness 2, 4
• This is critical because individual response varies and a single failed attempt does not predict overall efficacy

Combination therapy for inadequate response:

• If adequate dose of sumatriptan does not provide sufficient pain relief, combine with an NSAID or acetaminophen 4
• This approach is recommended by the American College of Physicians when monotherapy fails 4

Switching triptans:

• If inadequate response after dose optimization, consider switching to another triptan (almotriptan, eletriptan, frovatriptan, naratriptan, rizatriptan, or zolmitriptan) 4

Critical Contraindications

Absolute contraindications:

• Do not use with ergotamine, MAOIs, or within 24 hours of another triptan 2, 4
• Contraindicated in hemiplegic or basilar migraine, pregnancy, impaired hepatic function, or coronary artery disease 2, 4

Common pitfall: Approximately 40% of patients experience migraine recurrence within 24 hours after initial response, which can be effectively treated with an additional dose (respecting minimum intervals and maximum daily doses) 5, 6

Adverse Effects Profile

Common side effects:

• Oral: nausea, warmth, vomiting, vertigo, malaise, headache, chest pressure and heaviness 4
• Subcutaneous: injection site reactions (30%), chest pressure and heaviness 2, 4
• Adverse event incidence increases with dose: 19% (25 mg), 21% (50 mg), 30% (100 mg) 7

Monitoring consideration:

• The safety of treating more than 4 headaches in a 30-day period has not been established 1
• Monitor for medication overuse, which may lead to rebound headaches 8