5-HT1 AGONIST (TRIPTANS)...
EXAMPLES: Sumatriptan, zolmitriptan.
MECHANISM OF ACTION: Selective activation of 5-HT1 receptors that are predominantly
located in cranial blood vessel walls. 5-HT1 receptors mediate vasoconstriction thereby
relieving symptoms that are believed to result from the dilatation of intra- and extracranial
vessels.
- Treatment of acute migraine.
- Cluster headache.
- Ischaemic heart disease or coronary vasospasm.
- Peripheral vascular disease.
- Previous stroke or TIA.
- Severe hypertension.
- Dizziness.
- Paraesthesia.
- Tinnitus.
- Transient rise in blood pressure.
- Tachycardia and palpitations.
- Eliminated via metabolism by MAO-A. t½ is 2–6 h.
- No specific drug monitoring required.
- Increased risk of CNS toxicity with SSRIs and MAOIs.
- Plasma concentration of 5-HT1 agonists may be increased by macrolides and b blockers.
- 5-HT1 agonists are the preferred treatment for patients with migraines that do not respond to simple analgesia.
- 5-HT1 agonists should be used in the established headache phase of an attack; they are not suitable for migraine prophylaxis.
- Newer formulations include SC preparations, IN preparations and wafers for faster administration.
Tags:
Pharmacology