SUMATRIPTAN
Clinical safety rating: avoid
Contraindicated (not allowed)
Selective 5-HT1B/1D receptor agonist; causes vasoconstriction of cranial arteries and inhibits trigeminal nerve transmission.
| Metabolism | Primarily via monoamine oxidase A (MAO-A); minor via cytochrome P450 (CYP) enzymes. |
| Excretion | 60% renal (as indole acetic acid metabolite), 40% fecal; <3% unchanged in urine. |
| Half-life | 2.5 hours (range 1–4 h); clinically relevant for redosing interval of ≥2 h. |
| Protein binding | 14–21%, primarily to albumin and alpha-1-acid glycoprotein. |
| Volume of Distribution | 2.0–3.3 L/kg; indicates extensive tissue distribution. |
| Bioavailability | Oral: 15% (due to first-pass metabolism); subcutaneous: 97%; intranasal: 17% (with variability). |
| Onset of Action | Oral: 30–60 min; subcutaneous: 10–15 min; intranasal: 15–30 min. |
| Duration of Action | Oral: up to 24 h; subcutaneous: up to 24 h; intranasal: up to 24 h (pain-free response may be shorter). |
Sumatriptan is available as oral tablets (25 mg, 50 mg, 100 mg), subcutaneous injection (6 mg/0.5 mL), and nasal spray (5 mg, 20 mg). For acute migraine: oral: 50-100 mg at onset, may repeat after 2 hours (max 200 mg/day). Subcutaneous: 6 mg at onset, may repeat after 1 hour (max 12 mg/24h). Nasal spray: 20 mg in one nostril at onset, may repeat after 2 hours (max 40 mg/day).
| Dosage form | SPRAY |
| Renal impairment | No specific dose adjustment is recommended for renal impairment. However, sumatriptan and its metabolites are excreted renally, and caution is advised in severe renal impairment (CrCl <15 mL/min). No specific GFR-based guidelines are established. |
| Liver impairment | Contraindicated in severe hepatic impairment (Child-Pugh C). For mild to moderate hepatic impairment (Child-Pugh A or B): oral maximum dose is 50 mg; nasal spray: 5 mg single dose; subcutaneous: no specific adjustment, but caution advised due to reduced clearance. |
| Pediatric use | Not approved for pediatric use <18 years. However, off-label: adolescent (12-17 years): oral 25-100 mg at onset, may repeat after 2 hours (max 200 mg/day). Subcutaneous: 3-6 mg at onset (based on weight, e.g., 0.06 mg/kg). Nasal spray: 5-20 mg at onset. |
| Geriatric use |
| 1st trimester | Consult provider |
| 2nd trimester | Consult provider |
| 3rd trimester | Consult provider |
Clinical note
Other 5-HT1 agonists and MAOIs can have additive effects Contraindicated in ischemic heart disease and uncontrolled hypertension.
| Breastfeeding | Sumatriptan is excreted into human breast milk with a relative infant dose of 3.5% of maternal weight-adjusted dose (M/P ratio approximately 0.6-4.3). Clinical studies show no adverse effects in breastfed infants; however, wait at least 12 hours after injection or 24 hours after oral dose to breastfeed to minimize exposure. |
| Teratogenic Risk | FDA Pregnancy Category C. In first trimester, no increased risk of major congenital malformations from available data; however, animal studies show embryo lethality and increased malformations at high doses. Second and third trimester risks include potential for uterine hypertonus and fetal hypoxia during maternal use for migraine attacks; avoid during third trimester due to risk of premature uterine contractions. |
■ FDA Black Box Warning
Not recommended for use in patients with risk factors for coronary artery disease (e.g., hypertension, diabetes, smoking) unless a cardiovascular evaluation confirms absence of coronary artery disease.
| Common Effects | Chest pain |
| Serious Effects |
["Ischemic heart disease","History of myocardial infarction","Uncontrolled hypertension","Hemiplegic or basilar migraine","Concomitant use of MAO-A inhibitors or within 2 weeks of discontinuation","Severe hepatic impairment","Hypersensitivity to sumatriptan"]
| Precautions | ["Risk of myocardial ischemia, infarction, and Prinzmetal's angina","Life-threatening serotonin syndrome with concomitant serotonergic drugs","Elevations in blood pressure","Increased risk of cerebrovascular events","Overuse headache with frequent use"] |
Loading safety data…
| Limited data in elderly. Start with the lowest effective dose (e.g., oral 25 mg, subcutaneous 3 mg, nasal spray 5 mg). Caution due to potential for cardiovascular risk, hypertension, and reduced hepatic/renal function. Avoid in patients with uncontrolled hypertension or ischemic heart disease. |
| Fetal Monitoring | Monitor for signs of serotonin syndrome, hypertension, coronary vasospasm, and uterine hypertonus during administration. Fetal heart rate monitoring recommended during third trimester use due to risk of fetal distress from uterine contractions. |
| Fertility Effects | No human studies on fertility. Animal studies show no impairment of fertility at subtoxic doses. |