IMITREX
Pronunciation: soo-ma-TRIP-tan (IM-i-trex)


What it is5-HT1B/1D agonist causing cranial vasoconstriction; acute migraine and cluster headache.
Why this oneIts subcutaneous form has the fastest onset among triptans, useful when vomiting precludes oral treatment.
What limits itCoronary vasospasm makes it unsuitable in ischemic heart disease or uncontrolled hypertension; overuse causes rebound headache.
Animated chart of estimated U.S. prescriptions per year, Migraine-specific meds (1936–2026). Sumatriptan enters in 1993 (estimated).
Principal riskCoronary vasospasm; contraindicated in ischemic heart disease
Sulfonamide-derived drug — label silent
A sulfonamide by structure, without the N4 aromatic amine or N1 heterocycle; the label carries no sulfonamide warning, and Khan lists it among drugs with no or weak evidence of cross-reactivity. Almotriptan, same class, carries a label warning.
Open the sulfonamide hypersensitivity presentation → · sources [n] are on its References slide.
Legacy pregnancy categoryC
Defining liabilityAgent-specific vascular, serotonergic or hepatic risks; acute overdose is usually limited outside ergot or cardiovascular agents.
Read the full label on DailyMed ↗
NO BOXED WARNINGS
| FDA dosing | Population | Start | Target | Max |
|---|---|---|---|---|
| Acute migraine (with or without aura) | Adults | 25-100 mg PRN single dose | 50-100 mg PRN single dose | 200 mg/24h |
| Acute migraine, mild-moderate hepatic impairment | Adults | ≤50 mg PRN single dose | ≤50 mg PRN single dose | 50 mg single dose |
Renal Undefined
Hepatic Mild-moderate: max single dose 50 mg; severe: contraindicated
Max 200 mg per 24 hours; safety of treating >4 headaches/30 days not established
Available strengths
Pregnancy Registry/epidemiologic data have not detected increased birth defects; animal data show embryolethality/fetal abnormalities
Lactation Present in human milk; minimize infant exposure; transient breast pain reported
| Strength | #/mo | generic $/unit | CostPlus | |
|---|---|---|---|---|
| 25 mg | tab | per unit | $0.24/ea | offered |
| 50 mg | tab | per unit | $0.30/ea | offered |
| 100 mg | tab | per unit | $0.44/ea | offered |
Other forms: Sumatriptan SC injection (IMITREX)
Generic entry2016
This drug is routinely called serotonergic. By Gillman’s human-effect criteria it does not raise serotonin in the synapse.
Triptan receptor agonism is not a mechanistic serotonin-toxicity interaction with SRIs.
Label contraindicationMAOIs (concurrently or within 14 days). The label governs prescribing; Gillman’s point concerns serotonin toxicity only.
Gillman’s four human testsA measurable SERT affinity that fails all four is not clinical serotonicity.
Non-elevating action5-HT1B/1D agonist
Evidence confidenceHigh
Background: what serotonicity is · what is and is not an SRI · what counts as a relevant MAOI.
Open Sumatriptan in the interactive console ↗

Open Sumatriptan in the interactive console ↗