Ergot for migraine headache

Migraine headache treatment.

Ergot is a potent neurotoxin and vasoconstrictor found in a fungus that grows on rye, was one of the first effective migraine medications and has been a springboard for further migraine drug development.
Ergot is extracted from the dried C. purpurea, ergot contains numerous neurotoxic and vasoconstrictive alkaloids. The vasoconstrictive properties account for both the gangrenous form of ergot poisoning and ergot's medical applications in preventing postpartum hemorrhage and treating migraine headache. Since the potency and effects of naturally occurring ergot are unpredictable, turn-of-the-century chemists set about identifying and synthesizing the medically useful alkaloids found in ergot. Ergot proved to be a treasure chest--and a Pandora's box--of useful and fascinating chemical entities.
Ergotamine is not an analgesic and is ineffective for common tension head aches. Its vasoconstrictive effects have long been presumed to explain its efficacy for migraine, but the proposed mechanism of action of the ergot alkaloids has changed as understanding of migraine pathophysiology has evolved. Its main limitation is the relatively high incidence of side effects, which, according to different studies, range from 17 to 41%, compared with nonsteroidal anti-inflammatory drugs, for which the incidence of side effects is 5 to 28%. Nausea and vomiting predominate among the side effects observed following ergotamine ingestion, potentially exacerbating the nausea and vomiting commonly associated with migraine. Drowsiness, tiredness, or fatigue are also common, rendering it less useful for treating migraine attacks in the workplace. Overuse is associated with development of a chronic drug rebound headache (a headache pattern similar to tension headache superimposed on the migraine, which continues to occur) and risk of ergotism
DHE improved on ergotamine by reducing some of its more troublesome side effects. DHE avoids much of the hypertensive and emetic effects of ergotamine and also appears to be free from risk of drug rebound headaches. Because DHE is much less vasoconstrictive than ergotamine, it has been argued that its antimigraine action may have some other basis, such as an anti-inflammatory effect on blood vessels.