Sumatriptan injection

Generic name:

Sumatriptan succinate

Drug class:

Serotonin 5-HT1B/1D receptor agonist (triptan class)

Dosage form:

• Prefilled syringe (0.5 mL solution)
• Autoinjector (0.5 mL solution)

Root of administration:

Subcutaneous injection

Dose:

• Typical: 6 mg SC as a single dose
• Alternative: 4 mg SC in patients ≥18 years with lower body weight
• May repeat once after ≥1 hour if inadequate response
• Maximum: 12 mg in 24 hours
• Special populations (hepatic impairment): reduce dose per label

Mechanism of action:

Selective agonist at 5-HT1B/1D receptors leading to cranial vasoconstriction, inhibition of pro-inflammatory neuropeptide release, and interruption of trigeminal pain pathways.

Drug usage cases:

• Acute treatment of migraine with or without aura
• Acute treatment of cluster headache
• Off-label: pediatric migraine (ages ≥12 years)
• Off-label: treatment of refractory or chronic migraine adjunctively

Drug contra indications:

• History of ischemic heart disease or angina pectoris
• Coronary artery vasospasm (Prinzmetal’s angina)
• Cerebrovascular syndromes (e.g., stroke, TIA)
• Peripheral vascular disease
• Uncontrolled hypertension
• Basilar or hemiplegic migraine
• Severe hepatic impairment
• Hypersensitivity to sumatriptan or any component
• Use within 24 hours of ergotamine derivatives or other triptans

Side effects:

• Injection site pain, erythema, burning or swelling
• Sensation of pressure, tightness or heaviness in chest, neck, throat
• Paresthesia (tingling, numbness)
• Dizziness or vertigo
• Flushing or warm sensation
• Fatigue or asthenia
• Myalgia, muscle weakness
• Nausea or vomiting
• Abdominal discomfort
• Diaphoresis
• Taste perversion

Warnings:

• Serious cardiovascular events: myocardial ischemia, infarction, arrhythmias
• Cerebrovascular events: stroke, transient ischemic attacks
• Elevated blood pressure, hypertensive crises
• Risk of serotonin syndrome when combined with SSRIs, SNRIs, MAO inhibitors
• Avoid in patients with seizure disorders
• Caution in hepatic or renal impairment—dose adjustment required
• Monitor for signs of intestinal ischemia in patients with gastrointestinal risk factors
• Potential for medication overuse headache with frequent use

Use during pregnancy or breastfeeding:

Use in pregnancy only if potential benefit justifies potential risk. Animal studies have shown fetal harm at high doses; human data are limited. Excreted in breast milk; breastfeeding is not recommended for 8–24 hours post-dose. Consider alternative therapies for nursing mothers.