Drug Groups

approved

Description

A vasoconstrictor found in ergot of Central Europe. It is an alpha-1 selective adrenergic agonist and is commonly used in the treatment of migraine disorders. [PubChem]

Indication

For use as therapy to abort or prevent vascular headache, e.g., migraine, migraine variants, or so called "histaminic cephalalgia".

Pharmacology

Ergotamine is a vasoconstrictor and alpha adrenoreceptor antagonist. The pharmacological properties of ergotamine are extremely complex; some of its actions are unrelated to each other, and even mutually antagonistic. The drug has partial agonist and/or antagonist activity against tryptaminergic, dopaminergic and alpha adrenergic receptors depending upon their site, and it is a highly active uterine stimulant. It causes constriction of peripheral and cranial blood vessels and produces depression of central vasomotor centers. The pain of a migraine attack is believed to be due to greatly increased amplitude of pulsations in the cranial arteries, especially the meningeal branches of the external carotid artery. Ergotamine reduces extracranial blood flow, causes a decline in the amplitude of pulsation in the cranial arteries, and decreases hyperperfusion of the territory of the basilar artery. It does not reduce cerebral hemispheric blood flow.

Toxicity

Signs of overexposure include irritation, nausea, vomiting, headache, diarrhea, thirst, coldness of skin, pruritus, weak pulse, numbness, tingling of extremities, and confusion.

Affected Organisms

Biotransformation

Hepatic. Ergotamine is metabolized by the liver by largely undefined pathways, and 90% of the metabolites are excreted in the bile.

Absorption

The bioavailability of sublingually administered ergotamine has not been determined.

Half Life

2 hours

References

External Links