Donitriptan

Chemical structure of Donitriptan

Donitriptan is a pharmaceutical drug belonging to the class of triptans, which are used primarily in the treatment of migraine headaches. It acts as a selective serotonin receptor agonist, specifically targeting the 5-HT_1B and 5-HT_1D receptors.

Mechanism of Action

Donitriptan works by stimulating the 5-HT_1B and 5-HT_1D receptors, which are subtypes of the serotonin receptor. These receptors are located on the smooth muscle cells of cranial blood vessels and on the trigeminal nerve endings. Activation of these receptors leads to vasoconstriction of dilated intracranial blood vessels and inhibition of pro-inflammatory neuropeptide release, which are believed to be key mechanisms in the pathophysiology of migraines.

Pharmacokinetics

Donitriptan is administered orally and is absorbed into the bloodstream where it reaches peak plasma concentrations within a few hours. It is metabolized primarily in the liver and excreted via the kidneys. The half-life of donitriptan is relatively short, which is typical for drugs in the triptan class.

Clinical Use

Donitriptan is indicated for the acute treatment of migraine attacks with or without aura in adults. It is not intended for prophylactic therapy or for the management of cluster headaches. Patients are advised to take donitriptan as soon as migraine symptoms appear for optimal efficacy.

Side Effects

Common side effects of donitriptan include dizziness, fatigue, dry mouth, and nausea. As with other triptans, there is a risk of serotonin syndrome if donitriptan is taken in conjunction with other serotonergic drugs. Patients with cardiovascular conditions should use donitriptan with caution due to its vasoconstrictive properties.

Contraindications

Donitriptan is contraindicated in patients with a history of ischemic heart disease, cerebrovascular disease, or uncontrolled hypertension. It should not be used in patients with a known hypersensitivity to donitriptan or any of its components.

Related Pages

• Migraine
• Triptans
• Serotonin receptor
• Serotonin syndrome