What is the maximum dosage of Immetrex?

Maximum Dosage of Imitrex (Sumatriptan)

The maximum dosage of Imitrex depends on the route of administration: 12 mg per 24 hours for subcutaneous injection, 200 mg per day for oral tablets, and 40 mg per day for intranasal spray. 1

Subcutaneous Administration

• Initial dose: 6 mg subcutaneously, which may be repeated once after one hour if needed 1
• Maximum daily dose: 12 mg per 24 hours (two 6 mg injections) 1
• This route provides the most rapid onset of action, with headache relief typically occurring within 60-90 minutes in 73-79% of patients 2
• Subcutaneous administration is preferred when rapid relief is needed or when nausea/vomiting prevents oral medication 1

Oral Administration

• Initial dose: 25 to 100 mg, which may be repeated every two hours as needed 1
• Maximum daily dose: 200 mg per day 1
• Oral formulation is appropriate for patients who can tolerate oral medications and do not require immediate relief 1

Intranasal Administration

• Initial dose: 5 to 10 mg (one to two sprays) in one nostril 1
• May be repeated after 2 hours if needed 1
• Maximum daily dose: 40 mg per day 1
• Intranasal administration is particularly useful for patients who experience vomiting with migraines, wake with full-blown migraines, or want rapid relief without injections 3

Critical Safety Considerations

• Contraindications include concurrent use with ergotamine derivatives, MAOIs, use within 24 hours of another triptan, hemiplegic or basilar migraine, pregnancy, impaired hepatic function, and coronary artery disease 1
• Common adverse effects include nausea, warmth sensation, vomiting, vertigo, malaise, injection site reactions, and chest pressure/heaviness 1
• Some patients may experience transient reduction in peripheral skeletal muscle mitochondrial function 5-20 minutes after injection, manifesting as heaviness of limbs or muscle aches 4

Important Clinical Pearls

• Patients should trial a medication for two to three headache episodes before abandoning that therapy 1
• If one triptan is ineffective, a different triptan should be tried, as response varies among individuals 1
• Headache recurrence within 24 hours occurs in approximately 45% of sumatriptan-treated patients, which is higher than with dihydroergotamine (17.7%) 5
• Only approximately 15% of a maternal dose crosses the placenta over 4 hours, with passive transport mechanism 6