What is sumatriptan?

What is Sumatriptan

Sumatriptan is a selective serotonin 5-HT1B/1D receptor agonist used as a first-line medication for the acute treatment of moderate to severe migraine headaches with or without aura in adults. 1

Mechanism of Action

Sumatriptan works through several mechanisms to abort migraine attacks:

• Acts as a potent and selective agonist at vascular 5-HT1B/1D receptors, causing constriction of dilated cranial blood vessels that contribute to migraine pain 2, 3
• Inhibits the release of vasoactive neuropeptides from perivascular trigeminal nerve endings in the dura mater, reducing neurogenic inflammation 2
• Provides both peripheral and central neural inhibition of pain pathways involved in migraine 4

Available Formulations and Dosing

Sumatriptan is available in multiple formulations to accommodate different clinical scenarios 5:

• Oral tablets: 25 mg, 50 mg, and 100 mg doses 1

  • Standard dose is 100 mg at onset of migraine symptoms 5
  • May repeat after 2 hours if needed, maximum 200 mg per 24 hours 1

• Subcutaneous injection: 6 mg dose 5

  • Reaches peak blood concentration in approximately 15 minutes (fastest of all migraine-specific medications) 5
  • Effective in 70-82% of patients 5
  • Recommended dose for cluster headache treatment 5

• Intranasal spray: Available for patients with significant nausea/vomiting 5

• Orally disintegrating wafers: Useful when nausea impairs ability to swallow 5

Clinical Efficacy

Oral sumatriptan 100 mg provides pain-free response at 2 hours in approximately 1 in 5 patients (NNT = 5.1), with headache relief achieved in about 1 in 3 patients (NNT = 3.4) 4:

• 50-67% of patients achieve headache relief at 2 hours with oral sumatriptan 100 mg versus 10-31% with placebo 6
• Subcutaneous sumatriptan 6 mg achieves relief in 70-80% of patients within 1-2 hours 6, 4
• Effective for cluster headache: 74-75% of patients achieve relief within 15 minutes with subcutaneous administration 6
• Superior to ergotamine combinations: Consistently achieves significantly greater response rates than ergotamine 2 mg plus caffeine 200 mg 6

Headache Recurrence

A common pitfall with sumatriptan is headache recurrence 5, 6:

• Approximately 40% of initial responders experience headache recurrence, usually within 8-24 hours 5, 6
• Recurrent headaches respond well to a second dose of sumatriptan 5, 6
• This recurrence rate is higher than with some other treatments like dihydroergotamine 7

Common Side Effects

Sumatriptan is generally well tolerated, with most adverse events being transient 8, 2:

• Gastrointestinal effects: Nausea, vomiting, dry mouth (xerostomia) 8
• Cardiovascular sensations: Feelings of warmth, chest pressure, chest tightness, or heaviness (occurs in 3-5% of patients) 8, 2
• General effects: Malaise, vertigo, fatigue, dizziness, pain/discomfort/stiffness in neck, throat, or jaw 8, 2
• Injection site reactions: Occur in approximately 30-40% with subcutaneous administration, though markedly reduced with auto-injector use 2, 6
• Bitter taste: Common with intranasal formulation 7

Critical Contraindications

Sumatriptan is absolutely contraindicated in patients with ischemic vascular disease or uncontrolled hypertension 1, 2:

• Ischemic heart disease, previous myocardial infarction, or coronary artery disease 9, 1, 2
• Prinzmetal (variant) angina 1, 2
• Uncontrolled hypertension 8, 1
• Peripheral vascular disease (narrowing of blood vessels to legs, arms, stomach, or kidneys) 1
• History of stroke or transient ischemic attacks (TIAs) 1
• Hemiplegic or basilar migraines 8, 1
• Severe liver problems 1

Important Drug Interactions and Timing Restrictions

Do not use sumatriptan within 24 hours of other triptans or ergotamine-containing medications 8, 9, 1:

• Cannot be combined with: Almotriptan, eletriptan, frovatriptan, naratriptan, rizatriptan, zolmitriptan, ergotamine, or dihydroergotamine 1
• Use caution with antidepressants: SSRIs, SNRIs, tricyclic antidepressants, and MAOIs due to risk of serotonin syndrome 1
• Contraindicated with propranolol, cimetidine (for rizatriptan specifically) 9

Special Populations

• Pregnancy: Should only be used under strict specialist supervision 8
• Breastfeeding: Sumatriptan passes into breast milk; discuss feeding options with healthcare provider 1
• Children under 18: Safety and effectiveness not established 1
• First-time users with cardiac risk factors: Should take first dose in a medical setting with cardiac monitoring 1

Important Clinical Principles

Sumatriptan should be taken at the onset of migraine pain, not during the aura phase 5, 2:

• Reserved for moderate to severe migraines or mild to moderate migraines unresponsive to NSAIDs 5
• Not for migraine prevention: Only treats acute attacks, does not decrease frequency of migraines 1
• Limit use to avoid medication-overuse headache: Should not be used more than twice weekly 8
• Not effective for tension-type headaches or other non-migraine headaches 1

Serious Cardiovascular Warning

Heart attack and other serious heart problems can occur with sumatriptan, potentially leading to death 1:

Stop taking sumatriptan and seek emergency medical help immediately if experiencing 1:

• Chest discomfort lasting more than a few minutes
• Severe tightness, pain, pressure, or heaviness in chest, throat, neck, or jaw
• Pain in arms, back, neck, jaw, or stomach
• Shortness of breath
• Cold sweats, nausea, vomiting, or lightheadedness