-
Sumatriptan
- indication:For the treatment of migraine attacks with or without aura.
- pharmacologypharmacology:
- mechanism: The 5-HT<sub>1B</sub> and 5-HT<sub>1D</sub> receptors function as autoreceptors, which inhibit the firing of serotonin neurons and a reduction in the synthesis and release of serotonin upon activation. After sumatriptan binds to these receptors, adenylate cyclase activity is inhibited via regulatory G proteins, incrases intracellular calcium, and affects other intracellular events. This results in vasoconstriction and inhibtion of sensory nociceptive (trigeminal) nerve firing and vasoactive neuropeptide release.
- toxicity: Symptoms of overdose include convulsions, tremor, paralysis, inactivity, ptosis, erythema of the extremities, abnormal respiration, cyanosis, ataxia, mydriasis, salivation, and lacrimation.
- absorprion: Approximately 15%
- halflife: 2.5 hours
- roouteelimination: Only 3% of the dose is excreted in the urine as unchanged sumatriptan; 42% of the dose is excreted as the major metabolite, the indole acetic acid analogue of sumatriptan.
- volumedistribution: * 2.7 L/kg [subcutaneous dosing]
- clearance: * 1200 mL/min [Following a 6-mg SC injection]