What is the dosing regimen for Imitrex (sumatriptan) for migraine treatment?

Imitrex (Sumatriptan) Dosing for Migraine Treatment

For oral sumatriptan, start with 50-100 mg at migraine onset, which can be repeated after 2 hours if needed, with a maximum of 200 mg per 24 hours. 1

Route-Specific Dosing Regimens

Oral Administration

• Initial dose: 25 mg, 50 mg, or 100 mg at onset of migraine 1
• The 50 mg and 100 mg doses provide greater efficacy than 25 mg, though 100 mg may not offer significant advantage over 50 mg 1
• If headache persists or returns after 2 hours, repeat the dose with at least 2 hours between doses 1
• Maximum daily dose: 200 mg in 24 hours 2, 1
• The 50 mg dose offers the best balance of efficacy and tolerability, though many patients prefer or require 100 mg 3

Subcutaneous Administration

• Initial dose: 6 mg at migraine onset 2, 4, 5
• Can repeat once after 1 hour if needed 2, 4
• Maximum: 12 mg per 24 hours 2, 4, 5
• Provides fastest relief (within 15 minutes) with highest efficacy (70-82% response rate) 4

Intranasal Administration

• Initial dose: 5-20 mg (one to two sprays) in one nostril 2, 4, 5
• Can repeat after 2 hours if needed 2, 4, 5
• Maximum: 40 mg per 24 hours 2, 4, 5

Critical Timing Considerations

• Administer early in the headache phase when pain is still mild for optimal effectiveness 4
• Do not use during migraine aura 6
• Patients should trial sumatriptan for 2-3 headache episodes before determining effectiveness 4, 5, 7

Managing Inadequate Response

• If monotherapy fails, combine sumatriptan with an NSAID or acetaminophen 7
• Approximately 40% of patients experience headache recurrence within 8-12 hours, which can be treated with a second dose following minimum interval requirements 4, 6
• If inadequate response after dose optimization, switch to another triptan (almotriptan, eletriptan, frovatriptan, naratriptan, rizatriptan, or zolmitriptan) 7

Absolute Contraindications

• Coronary artery disease, previous myocardial infarction, or Prinzmetal angina 4, 6
• Hemiplegic or basilar migraine 2, 4, 5
• Uncontrolled hypertension 4, 6
• Use within 24 hours of ergotamine or another triptan 2, 4, 5
• Current MAOI use 2, 4, 5
• Pregnancy 2, 5
• Impaired hepatic function (if used, maximum single dose 50 mg) 2, 5, 1

Common Adverse Effects

• Oral: nausea, warmth, vomiting, vertigo, malaise, fatigue, dizziness 2, 7, 6
• Subcutaneous: injection site reactions (approximately 30% of patients), chest pressure and heaviness 5, 7, 6
• Chest symptoms occur in 3-5% of patients but rarely associated with myocardial ischemia 4, 6

Critical Safety Warning

Frequent, repeated use of sumatriptan risks development of medication overuse headache 4. The safety of treating more than 4 headaches in a 30-day period has not been established 1.