Eletriptan (20mg)

Clinical Pharmacologist's Monograph

⚠️ Prescription Only: This medicine is Schedule H/H1. Do not self-medicate.

1. Clinical Overview

Eletriptan is a selective serotonin (5-HT1B/1D) receptor agonist, commonly known as a 'triptan', used for the acute treatment of migraine headaches with or without aura in adults. It is not intended for prophylactic therapy of migraine or for the treatment of cluster headaches, hemiplegic, or basilar migraine. It is a second-generation triptan with high oral bioavailability and rapid absorption, making it effective for many patients.

OnsetDurationBioavailability
30 minutes to 2 hoursUp to 24 hours (sustained relief)Approximately 50%

2. Mechanism of Action

Eletriptan binds with high affinity to 5-hydroxytryptamine 1B/1D (5-HT1B/1D) receptors located on intracranial blood vessels and sensory nerve terminals of the trigeminal system. This binding causes vasoconstriction of dilated cerebral blood vessels, inhibits the release of pro-inflammatory neuropeptides (like CGRP and substance P), and reduces transmission in trigeminovascular pain pathways.

3. Indications & Uses

  • Acute treatment of migraine with aura in adults
  • Acute treatment of migraine without aura in adults

4. Dosage & Administration

Adult Dosage: Initial dose: 20mg or 40mg taken as a single dose at the onset of migraine headache. If headache recurs, a second dose may be taken after at least 2 hours. Maximum daily dose: 80mg.

Administration: Tablet should be swallowed whole with a glass of water. Can be taken with or without food. Take at the earliest sign of a migraine headache. Do not crush or chew. If no response to the first dose, a second dose for the same attack is not recommended. For a subsequent migraine attack, a new dose can be taken.

5. Side Effects

Common side effects may include:

  • Dizziness
  • Somnolence (drowsiness)
  • Asthenia (weakness/fatigue)
  • Nausea
  • Chest tightness/pressure/discomfort (non-cardiac)
  • Paresthesia (tingling sensation)
  • Throat tightness

6. Drug Interactions

DrugEffectSeverity
Ketoconazole, Itraconazole, VoriconazoleMarkedly increases eletriptan plasma levels (AUC increased up to 6-fold). Increases risk of adverse effects.Major - Contraindicated within 72 hours
Clarithromycin, ErythromycinSignificantly increases eletriptan plasma levels. Increases risk of adverse effects.Major - Contraindicated within 72 hours
Ritonavir, Nelfinavir, other strong CYP3A4 inhibitorsMarkedly increases eletriptan plasma levels. Increases risk of adverse effects.Major - Contraindicated within 72 hours
Other Triptans (Sumatriptan, Rizatriptan, etc.) or Ergot derivativesIncreased risk of vasospastic reactions. Additive vasoconstrictive effects.Major - Contraindicated within 24 hours
SSRIs/SNRIs (e.g., Sertraline, Fluoxetine, Venlafaxine)Potential increased risk of serotonin syndrome (weakness, hyperreflexia, incoordination).Moderate - Monitor closely
MAO Inhibitors (e.g., Phenelzine, Selegiline)Theoretical increased risk of serotonin syndrome.Moderate - Use with caution

7. Patient Counselling

  • DO take at the first sign of a migraine headache.
  • DO take with water; it can be taken with or without food.
  • DO wait at least 2 hours before considering a second dose for the same headache, if needed.
  • DONT take a second dose for the same headache if the first dose provided no relief.
  • DONT take more than 80mg in a 24-hour period.
  • DONT take within 24 hours of any other migraine medication like another triptan or ergotamine.
  • DONT use to treat more than 4 migraine headaches in a 30-day period without consulting your doctor (risk of medication-overuse headache).

8. Toxicology & Storage

Overdose: Hypertension, cardiovascular events (chest pain, arrhythmia), drowsiness, seizures, loss of coordination. In extreme cases, coronary vasospasm and myocardial infarction.

Storage: Store below 30°C. Protect from light and moisture. Keep out of reach of children. Do not use after the expiry date printed on the pack.