Sumatriptan

# Sumatriptan ## Overview - **Classification**: Serotonin (5-HT1B/1D) receptor agonist; Triptan - **Mechanism**: Selectively activates 5-HT1B/1D receptors on intracranial blood vessels and trigeminal nerve endings. - Causes vasoconstriction of dilated intracranial blood vessels. - Inhibits pro-inflammatory neuropeptide release from trigeminal nerve. ## Primary Indications 1. **Acute Migraine** - Treatment of acute migraine attacks with or without aura. 2. **Acute Cluster Headache** - Treatment of acute cluster headache episodes (SC and nasal spray only). ## Adult Dosing ### Standard Dosing **Acute Migraine** (Oral) - **Dose**: **25 mg**, **50 mg**, or **100 mg** - **Frequency**: May repeat once after **2 hours** if headache recurs or only partial response. - **Route**: Oral - **Maximum**: **200 mg** in 24 hours. **Acute Migraine** (Subcutaneous) - **Dose**: **6 mg** - **Frequency**: May repeat once after **1 hour** if headache recurs. - **Route**: Subcutaneous (SC) - **Maximum**: **12 mg** in 24 hours. **Acute Migraine / Cluster Headache** (Nasal Spray) - **Dose**: **5 mg**, **10 mg**, or **20 mg** in one nostril. - For cluster: **20 mg** in one nostril. - **Frequency**: May repeat once after **2 hours** (migraine); **2 hours** (cluster). - **Route**: Nasal - **Maximum**: **40 mg** in 24 hours. ### Dose Adjustments - **Renal Impairment**: No specific dose adjustment recommended. - Use with caution in severe renal impairment. - **Hepatic Impairment**: Contraindicated in **severe** hepatic impairment. - In mild-moderate impairment, consider **50 mg** oral as initial single dose. - **Elderly Patients**: Not recommended in patients **>65 years** due to increased cardiovascular risk. - If used, careful cardiovascular assessment is essential. ## Pediatric Dosing *Sumatriptan is generally not recommended for routine use in children <18 years due to limited safety/efficacy data and potential for increased adverse effects.* ### Neonates (0-28 days) - **Dose**: Not recommended. - **Special Notes**: Safety and efficacy not established. ### Infants (1-12 months) - **Dose**: Not recommended. - **Special Notes**: Safety and efficacy not established. ### Children (1-12 years) - **Dose**: Not generally recommended for routine use. - **Special Notes**: Safety and efficacy not established for this age group. - Alternative acute migraine treatments should be considered. ### Adolescents (13-18 years) - **Dose**: Oral tablets **25 mg** or **50 mg**. - **Frequency**: May repeat once after **2 hours**. - **Maximum**: **100 mg** in 24 hours. - **Special Notes**: Limited evidence for efficacy; use with caution. - SC and nasal formulations generally not recommended. ## Safety Information ### Contraindications - **Absolute**: Ischemic heart disease (angina, MI history, silent ischemia). - **Absolute**: Cerebrovascular syndromes (stroke, TIA history). - **Absolute**: Peripheral vascular disease. - **Absolute**: Uncontrolled hypertension. - **Absolute**: Hemiplegic or basilar migraine. - **Absolute**: Concurrent use with MAOIs (within **2 weeks**). - **Absolute**: Concurrent use with ergotamine-containing or other triptans (within **24 hours**). - **Absolute**: Severe hepatic impairment. ### Common Adverse Effects - **Very Common (>10%)**: Injection site reactions (SC), dizziness, tingling/numbness. - **Common (1-10%)**: Chest pain/tightness, flushing, neck pain/stiffness, nausea/vomiting, weakness, malaise. - **Serious but Rare**: Myocardial ischemia/infarction, arrhythmias, stroke, seizure, serotonin syndrome. ### Key Drug Interactions - **MAOIs**: Increased sumatriptan levels and toxicity. **Contraindicated** (within **2 weeks**). - **Ergotamine/Other Triptans**: Additive vasoconstriction, prolonged vasospastic reaction. **Contraindicated** (within **24 hours**). - **SSRIs/SNRIs**: Increased risk of serotonin syndrome. Monitor for symptoms (agitation, confusion, tachycardia). - **Propranolol**: May increase sumatriptan Cmax and AUC. Use with caution. ## Monitoring & Follow-up - **Before Treatment**: Assess cardiovascular risk factors (e.g., hypertension, hyperlipidemia, diabetes, smoking). - **Before Treatment**: Rule out underlying cardiovascular disease, especially in patients with risk factors. - **During Treatment**: Monitor for chest discomfort, jaw/neck pain, or other symptoms suggestive of cardiac ischemia. - **Clinical Signs**: Watch for signs of serotonin syndrome (agitation, confusion, hyperreflexia). - **Clinical Signs**: Monitor for allergic reactions (rash, angioedema). ## Clinical Pearls - 💡 **Tip 1**: Administer sumatriptan as early as possible after migraine onset, but it's effective at any stage. - 💡 **Tip 2**: Do not use sumatriptan for migraine prophylaxis or to prevent cluster headaches. - 💡 **Tip 3**: If the first dose is ineffective, do not take a second dose without medical advice (for migraine). - 💡 **Tip 4**: Subcutaneous injection has the fastest onset of action (**~10-15 minutes**) for rapid relief. > **⚠️ Important**: This information is for educational purposes only. Always consult current prescribing information, local guidelines, and clinical judgment before prescribing.