Imigran (Sumatriptan)

• Sumatriptan is used for the acute treatment of migraine, a neurovascular headache disorder.
• Migraine attack: provides rapid relief of headache pain and associated symptoms such as nausea, photophobia, and phonophobia.
• Cluster headache: can abort acute cluster headache episodes when administered early.

• Sumatriptan acts as an agonist at serotonin 5‑HT1B and 5‑HT1D receptors located on intracranial blood vessels and sensory trigeminal nerve endings. Activation of 5‑HT1B receptors induces cranial vasoconstriction, while 5‑HT1D stimulation inhibits release of pro‑inflammatory neuropeptides. Together these actions reduce vascular dilation and neurogenic inflammation, alleviating migraine headache.

The most frequently reported reactions to subcutaneous sumatriptan include both mild and more serious events.

Common Side Effects

• Injection site pain: mild discomfort at the injection site.
• Tingling or numbness: transient paresthesia in extremities.
• Warmth or flushing: sensation of heat or reddening.
• Nausea: mild upset stomach.

Serious or Rare Side Effects

• Chest discomfort or tightness: possible cardiac ischemia.
• Serotonin syndrome: agitation, hyperthermia, muscle rigidity.
• Allergic reactions: rash, swelling, anaphylaxis.

When prescribing Imigran, clinicians should consider several safety precautions to minimize risks.

• Assess cardiovascular risk: evaluate patients with coronary artery disease, uncontrolled hypertension, or cerebrovascular disease before use.
• Contraindicated in ischemic heart disease: avoid in patients with a history of myocardial infarction or angina.
• Avoid concomitant ergotamine: combined vasoconstriction may lead to severe vascular events.
• Caution with serotonergic agents: monitor for signs of serotonin syndrome when used with SSRIs, SNRIs, or MAO inhibitors.
• Pregnancy and lactation: safety not established; use only if potential benefit justifies potential risk.
• Store at ambient temperature: keep in original container, protect from moisture and light.

Sumatriptan may interact with other medicines, affecting its safety or effectiveness.

Major Interactions (Avoid)

• Ergotamine derivatives: additive vasoconstriction can cause severe hypertension.
• Monoamine oxidase inhibitors (MAOIs) within 14 days: risk of hypertensive crisis.
• Other triptans: concurrent use increases risk of vasospasm.
• Serotonergic antidepressants (SSRIs, SNRIs, TCAs): may precipitate serotonin syndrome.

Moderate Interactions (Monitor Closely)

• Beta‑blockers: may reduce the therapeutic response to sumatriptan.
• CYP3A4 inhibitors (e.g., ketoconazole, erythromycin): can increase plasma concentrations of sumatriptan.