What are the potential side effects of sumatriptan (Imitrex)?

Sumatriptan Side Effects

Sumatriptan commonly causes chest discomfort, fatigue, dizziness, paresthesia, and unpleasant taste, with rare but serious cardiovascular complications including myocardial infarction in patients with or without cardiac risk factors. 1

Common Side Effects

Sumatriptan side effects vary by route of administration, with oral administration generally having fewer side effects than subcutaneous injection:

Oral Administration Side Effects:

• Tingling or numbness in fingers or toes
• Warm or cold sensations
• Weakness, drowsiness, or fatigue
• Pain, discomfort, or stiffness in neck, throat, jaw, or chest
• Dizziness
• Nausea and vomiting
• Malaise 1, 2

Subcutaneous Administration Side Effects:

• Injection site reactions (pain and redness) in approximately 40% of patients
• Higher incidence of adverse events compared to oral route 2, 3

Serious Side Effects

Cardiovascular Effects:

• Chest tightness or pressure occurs in 3-5% of patients 2
• Potential for myocardial infarction even in patients without cardiac risk factors 4
• Changes in color or sensation in fingers and toes (Raynaud's syndrome) 1

Neurological Effects:

• Seizures (can occur even in patients with no seizure history)
• Serotonin syndrome (especially when combined with SSRIs or SNRIs) 1

Gastrointestinal Effects:

• Stomach and intestinal problems (gastrointestinal and colonic ischemic events)
• Symptoms include sudden or severe stomach pain, stomach pain after meals, weight loss, nausea/vomiting, constipation/diarrhea, bloody diarrhea, fever 1

Vascular Effects:

• Problems with blood circulation to legs and feet (peripheral vascular ischemia)
• Symptoms include cramping/pain in legs/hips, heaviness in leg muscles, burning/aching pain in feet/toes, numbness/tingling/weakness in legs, cold feeling or color changes in legs/feet 1

Contraindications

Sumatriptan should not be used in patients with:

• Heart problems or history of heart problems
• Narrowing of blood vessels (peripheral vascular disease)
• Uncontrolled high blood pressure
• Severe liver problems
• Hemiplegic or basilar migraines
• History of stroke or TIAs
• Recent use (within 24 hours) of other triptans or ergotamine derivatives 1

Risk Factors for Adverse Effects

Patients with the following conditions are at higher risk for adverse cardiovascular effects:

• High blood pressure
• High cholesterol
• Smoking history
• Overweight/obesity
• Diabetes
• Family history of heart disease 1

Medication Overuse

Excessive use of sumatriptan can lead to medication overuse headaches, potentially worsening the condition it's meant to treat 1.

Dosing Considerations

• Do not exceed 200 mg of oral sumatriptan in a 24-hour period
• If headache returns, a second dose can be taken 2 hours after the first dose
• For subcutaneous administration, 6 mg is the standard dose with similar efficacy but fewer side effects than 12 mg 1, 2, 3

Special Considerations

• Women with migraine with aura have significantly higher risk of ischemic stroke (relative risk 2.08)
• Combined hormonal contraceptives with estrogens are contraindicated in women with migraine with aura due to increased stroke risk 5
• Triptans should be avoided on the day of surgical procedures due to theoretical drug interactions with commonly used perioperative medications 6

By understanding these potential side effects, patients and healthcare providers can make informed decisions about using sumatriptan while monitoring for adverse reactions.