Ergotamine
Medicinal Chemistry
Molecular Weight
581.67
Molecular Formula
C33H35N5O5
IUPAC Name
(5'alpha)-12'-hydroxy-2'-methyl-3',6',18-trioxo-5'-benzylergotaman
Pharmacognosy
Biological Source
Claviceps purpurea
Active Constituents
Ergotamine
Pharmacology & Synthesis
Mechanism of Action
Partial agonist/antagonist at serotonin (5-HT1B/1D) and alpha-adrenergic receptors.
Pharmacokinetics (ADME)
A: Poor and erratic oral absorption.
D: Highly protein bound.
M: Hepatic via CYP3A4.
E: Biliary/Feces.
Pharmacodynamics
Constricts cranial blood vessels, reducing pulsation responsible for migraine pain.
Synthesis Pathway
Synthesized from L-tryptophan and dimethylallyl pyrophosphate.
Safety, Warnings & Interactions
Adverse Effects
Nausea, vomiting, peripheral ischemia, ergotism (gangrene).
Contraindications
Pregnancy, peripheral vascular disease, coronary artery disease.
Drug Interactions
CYP3A4 inhibitors cause severe vasospasm.
Pharmaceutics & Compendia
Dosage Forms
Tablets, Suppositories, Sublingual
Official Compendia
IP, BP, USP