Last reviewed 2026-04-20 · How we verify

Imitrex (SUMATRIPTAN)

Imitrex works by binding to serotonin receptors in the brain, specifically the 5-HT1D subtype, to constrict blood vessels and block pain pathways.

Imitrex (Sumatriptan) is a serotonin-1b and serotonin-1d receptor agonist, a small molecule developed by GlaxoSmithKline and approved by the FDA in 1992 for the treatment of cluster headache syndrome and migraine. It targets the 5-hydroxytryptamine receptor 1D, providing relief from migraine symptoms. As an off-patent medication, Imitrex is available from multiple generic manufacturers. Key safety considerations include its short half-life of 1.7 hours and limited bioavailability of 14%. Commercially, Imitrex remains a branded option alongside generic alternatives.

At a glance

Mechanism of action

Mechanism of Action. Sumatriptan is an agonist for vascular 5-hydroxytryptamine1 receptor subtype (probably member of the 5-HT1D family) having only weak affinity for 5-HT1A, 5-HT5A, and 5-HT7 receptors and no significant affinity (as measured using standard radioligand binding assays) or pharmacological activity at 5-HT2, 5-HT3, or 5-HT4 receptor subtypes or at alpha1-, alpha2-, or beta-adrenergic; dopamine1; dopamine2; muscarinic; or benzodiazepine receptors.The vascular 5-HT1 receptor subtype that sumatriptan activates is present on cranial arteries in both dog and primate, on the human basilar artery, and in the vasculature of human dura mater and mediates vasoconstriction. This action in humans correlates with the relief of migraine headache. In addition to causing vasoconstriction, experimental data from animal studies show that sumatriptan also activates 5-HT1 receptors on peripheral terminals of the trigeminal nerve innervating cranial blood vessels. Such an action may also con

Approved indications

• Cluster headache syndrome
• Migraine

Common side effects

• Paresthesia (all types)
• Pain and other pressure sensations
• Sensation warm/cold
• Chest pain/tightness/pressure and/or heaviness
• Neck/throat/jaw -pain/ tightness/pressure
• Pain location specified
• Other pressure/tightness/ heaviness
• Malaise/fatigue
• Vertigo
• Hypotension
• Palpitations
• Dystonia

Drug interactions

• citalopram
• fluoxetine
• fluvoxamine
• nefazodone
• paroxetine
• sertraline
• tapentadol
• tranylcypromine
• venlafaxine

Key clinical trials

• Pharmacokinetics and Safety of Commonly Used Drugs in Lactating Women and Breastfed Infants
• Drug-Drug Interaction Study of Evobrutinib and Transporter Substrates (PHASE1)
• Quality Improvement and Practice Based Research in Neurology Using the EMR (PHASE4)
• Prochlorperazine vs Imitrex for Acute Migraine in the Emergency Department (NA)
• i-NEED: NEw migrainE Drugs Database
• Assessment of Oral Caffeine Intake in Changing the Severity of Acute Migraine Attack Using VAS Score Among Patients Attending Headache and Neurology Outpatients Clinic of Ainshams University Hospitals (PHASE4)
• Nebulized Dexmedetomidine Versus Oral Sumatriptan in Treatment of Post Dural Puncture Headache in Cesarean Section (NA)
• Use of the Combination of Sumatriptan and Naproxen in the Acute Treatment of Migraine: Real World Evidence Study

Patents

Primary sources

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