What is the maximum recommended dose of sumatriptan (Imitrex) per day for a patient with a history of migraine headaches, considering potential cardiovascular disease, hypertension, and impaired renal or hepatic function?

Maximum Daily Dose of Sumatriptan

The maximum dose of sumatriptan per day is 200 mg for oral tablets, 12 mg for subcutaneous injection, or 40 mg for intranasal spray within any 24-hour period. 1, 2

Route-Specific Maximum Daily Doses

Oral Sumatriptan

• The FDA-approved maximum daily dose is 200 mg in a 24-hour period 1
• Individual doses are 25 mg, 50 mg, or 100 mg, with the 50-100 mg doses providing greater effect than 25 mg 1
• If the migraine has not resolved by 2 hours after the first dose, a second dose may be administered at least 2 hours after the first dose 1
• The 100 mg dose may not provide greater effect than the 50 mg dose, but carries higher risk of adverse reactions 1

Subcutaneous Sumatriptan

• The maximum daily dose is 12 mg per 24 hours (two 6 mg injections) 2
• The standard dose is 6 mg at migraine onset, which may be repeated once after 1 hour if needed 2
• Subcutaneous administration provides the fastest relief (within 15 minutes) with 70-82% efficacy 3, 2

Intranasal Sumatriptan

• The maximum daily dose is 40 mg per 24 hours 2
• Individual doses range from 5-20 mg, which may be repeated after 2 hours 2

Critical Dosing Intervals Between Routes

• When switching from subcutaneous to oral sumatriptan, allow at least 2 hours between doses 1
• After initial treatment with sumatriptan injection, additional oral tablets (up to 100 mg/day) may be given with an interval of at least 2 hours between tablet doses 1

Special Population Dosing Adjustments

Hepatic Impairment

• In mild to moderate hepatic impairment, the maximum single dose should not exceed 50 mg 1
• Sumatriptan is contraindicated in severe hepatic impairment 1

Cardiovascular Disease, Hypertension, or Renal Impairment

• Sumatriptan is contraindicated in patients with ischemic vascular conditions, vasospastic coronary disease, or uncontrolled hypertension 3, 2, 4
• No specific renal dose adjustment is provided in the FDA label, but cardiovascular evaluation is recommended for patients with cardiovascular risk factors 1

Frequency Limitation to Prevent Medication Overuse Headache

• Limit sumatriptan use to no more than 10 days per month (approximately 2 days per week) to prevent medication-overuse headache 2
• The safety of treating more than 4 headaches in a 30-day period has not been established 1
• Frequent use beyond this threshold can paradoxically increase headache frequency and lead to daily headaches 2

Critical Contraindications and Drug Interactions

• Never use sumatriptan within 24 hours of ergotamine, dihydroergotamine (DHE), or another triptan 2
• Sumatriptan is contraindicated with current MAOI use 2
• Do not administer to patients with hemiplegic or basilar migraine 2

Common Prescribing Pitfall

• If a patient requires more than the maximum daily dose or needs treatment more frequently than twice weekly, initiate preventive therapy immediately rather than increasing acute medication frequency, as this creates a cycle of medication-overuse headache 2