Side Effects of Sumatriptan (Imitrex)
Sumatriptan can cause several significant side effects, most commonly including chest pressure/tightness, paresthesias, gastrointestinal effects, and sensory disturbances, with rare but serious cardiovascular risks in certain populations. 1, 2
Common Side Effects
- Cardiovascular effects: Chest pressure, tightness, heaviness, or warmth are frequently reported (3-5% of patients) 1, 3
- Neurological effects: Dizziness, tingling or numbness in fingers or toes, feeling weak, drowsy, or tired 2
- Gastrointestinal effects: Nausea, vomiting, and dry mouth (xerostomia) 1
- Musculoskeletal effects: Pain, discomfort, or stiffness in neck, throat, or jaw 1, 2
- General effects: Malaise, vertigo, and feeling of warmth or cold 1, 4
- Administration site reactions: Injection site reactions occur in approximately 30-40% of patients receiving subcutaneous sumatriptan 4, 5
Serious Side Effects
- Cardiovascular complications: Though rare, sumatriptan can cause serious heart problems including heart attack, which may lead to death 2
- Raynaud's syndrome: Changes in color or sensation in fingers and toes 2
- Gastrointestinal and colonic ischemic events: Symptoms include sudden or severe stomach pain, stomach pain after meals, weight loss, nausea/vomiting, constipation/diarrhea, bloody diarrhea, and fever 2
- Peripheral vascular ischemia: Cramping and pain in legs or hips, heaviness in leg muscles, burning pain in feet or toes, numbness or weakness in legs, cold feeling or color changes in extremities 2
- Serotonin syndrome: Particularly when used with antidepressants (SSRIs, SNRIs, TCAs, MAOIs), symptoms include hallucinations, agitation, coma, fast heartbeat, blood pressure changes, high body temperature, tight muscles, trouble walking, and seizures 2
- Seizures: Can occur even in patients with no history of seizures 2
- Medication overuse headache: Can occur with frequent use (more than twice weekly) 3, 2
Contraindications
Sumatriptan should not be used in patients with:
- Ischemic heart disease, history of heart attack, or coronary artery disease 1, 2
- Uncontrolled hypertension 1, 2
- Hemiplegic or basilar migraine 1, 2
- Recent use (within 24 hours) of ergotamine-containing medications or other triptans 1, 2
- Impaired hepatic function 1
- Peripheral vascular disease 2
- History of stroke or TIAs 2
Clinical Considerations
- Headache recurrence occurs in approximately 40% of patients who initially respond to oral or subcutaneous sumatriptan, usually within 24 hours 4, 5
- A second dose can be taken if headache returns, but no more than 200 mg should be taken in a 24-hour period 2
- To avoid medication-overuse headache, acute therapy should be limited to no more than twice weekly 3
- If a patient experiences unpleasant sensory disturbances with sumatriptan, trying a different triptan may be beneficial 6
- Patients should try sumatriptan for 2-3 headache episodes before abandoning this therapy 6
- If scheduled for surgery, sumatriptan should be taken preoperatively but held on the day of operation 6
Special Populations
- Pregnancy: Should only be used under strict specialist supervision 1
- Patients with cardiovascular risk factors: Should have a heart exam before using sumatriptan 2
- Breastfeeding women: Sumatriptan passes into breast milk and may harm the baby 2
The side effect profile of sumatriptan must be carefully considered against its proven efficacy in treating migraine and cluster headaches, with particular attention to cardiovascular risk factors before prescribing.