Naratriptan

Absorption

Well absorbed (74% oral biovaility), absorption is rapid with peak plasma concentrations after 2-5 hours. The rate of absorption is slower during a migraine attack.

Toxicity

Symptoms of overdose include light-headedness, loss of coordination, tension in the neck, and tiredness.

The Uses of Naratriptan

Naratriptan is a triptan drug that is used for the treatment of migraine headaches.

Background

Naratriptan is a triptan drug that is selective for the 5-hydroxytryptamine1 receptor subtype. It is typically used for the treatment of migraine headaches.

Indications

For the acute treatment of migraine attacks with or without aura in adults.

Pharmacokinetics

Naratriptan is a selective agonist of serotonin (5-hydroxytryptamine; 5-HT) type 1B and 1D receptors. It is structurally and pharmacologically related to other selective 5-HT1B/1D receptor agonist. Naratriptan has only a weak affinity for 5-HT1A, 5-HT5A, and 5-HT7 receptors and no significant affinity or pharmacological activity at 5-HT2, 5-HT3 or 5-HT4 receptor subtypes or at alpha1-, alpha2-, or beta-adrenergic, dopamine1,; dopamine2; muscarinic, or benzodiazepine receptors. This action in humans correlates with the relief of migraine headache. In addition to causing vasoconstriction, experimental data from animal studies show that Naratriptan also activates 5-HT1 receptors on peripheral terminals of the trigeminal nerve innervating cranial blood vessels, which may also contribute to the antimigrainous effect of Naratriptan in humans.

Metabolism

Primarily hepatic. In vitro, naratriptan is metabolized by a wide range of cytochrome P450 isoenzymes into a number of inactive metabolites.