Section 02 · Monograph
Sumatriptan
Reviewed Nov 2026FDA label
ImitrexTriptan
- Forms
- Tab: 25, 50, 100mg | SC: 4, 6mg | NS: 5, 20mg
- Dose
- 50-100mg PRN (max 200mg/day)
- MOA
- 5-HT1B/1D agonist; cranial vasoconstriction
Indications
- Acute treatment of migraine with or without aura in adultsFDA-labeled
Off-Label Uses
- Cluster headache (SC formulation commonly used)Off-label
Mechanism of Action
- Selective serotonin 5-HT1B/1D receptor agonist
- Causes cranial (and coronary) vasoconstriction via 5-HT1B receptors
- Inhibits release of vasoactive neuropeptides (e.g., CGRP) from trigeminal sensory nerves via 5-HT1D receptors, reducing neurogenic inflammation
Full Dosing
Adult / usual
- Oral: 25-100mg as a single dose PRN; may repeat after 2 hours if migraine returns, max 200mg/day
- Subcutaneous: 4-6mg PRN, max 12mg/day given as 2 doses at least 1 hour apart
- Nasal spray: 5-20mg PRN per labeled schedule
Pediatric
- Not established for pediatric use for most formulations — check current label for age-specific approvals
Contraindications
- History of hypersensitivity to sumatriptan
- Ischemic or vasospastic coronary artery disease (angina, prior MI, documented silent ischemia, Prinzmetal's angina)
- Uncontrolled hypertension
- Hemiplegic or basilar migraine
- Use of another 5-HT1 agonist (triptan or ergot-type medication) within 24 hours
- Use of an MAOI within the past 2 weeks
- Severe hepatic impairment
Drug Interactions
- Contraindicated with other 5-HT1 agonists within 24 hours (additive vasospasm risk)
- Serotonin syndrome risk with SSRIs, SNRIs, TCAs, and MAOIs — discontinue sumatriptan immediately if serotonin syndrome develops
- Contraindicated with MAOIs within 2 weeks (increased sumatriptan exposure)
Adverse Effects
- Common: paresthesia, warm/cold sensation, chest pain/tightness/pressure, neck/throat/jaw tightness, vertigo, malaise/fatigue
- Serious but rare: myocardial ischemia/infarction, coronary vasospasm, arrhythmias
- Seizures reported, including in patients without a prior seizure history — use caution with epilepsy or lowered seizure threshold
Monitoring Parameters
- Cardiovascular risk assessment before first dose in patients with risk factors (diabetes, smoking, hypertension, obesity, strong family history of CAD, postmenopausal women, men over 40)
- Consider ECG monitoring with the first dose in higher cardiovascular-risk patients
Pregnancy & Lactation
- Pregnancy exposure registry data have not shown an increased frequency of birth defects compared to the general population
- Animal studies showed embryolethality and fetal abnormalities at high exposures