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What should I know about ergot alkaloids?

        Health | Headache

Ergot alkaloids are derived from a common fungus. They are only used to treat migraine and cluster headaches. Two ergot alkaloids commonly used are ergotamine and DHE.

Ergotamine is used to treat migraine attacks. It does this by narrowing blood vessels throughout the body, especially blood vessels in the head. To be effective, it must be taken at the start of a headache attack. Ergotamine can only be taken orally. Therefore, you may not be able to get relief from it if you have severe nausea or vomiting when you have an attack.

Dihydroergotamine or DHE can be used to treat both migraine and cluster headaches. It works in a similar way to ergotamine, but it does not narrow blood vessels throughout the body as much as ergotamine does. Because of this, DHE is considered somewhat safer to use.

Unlike ergotamine, DHE may still be effective if it is used well into the course of a headache. DHE may be taken either by injection under the skin or by nasal spray. The fastest pain relief comes from injection. DHE may be used at home. It also is a common treatment for migraine in emergency departments.

How do ergot alkaloids work?

Nerves and widening blood vessels in the head both play a role in bringing on migraine and cluster headaches. The ergot alkaloids ergotamine and DHE work by canceling out the widening of blood vessels linked to these headaches and actually narrowing them.

What are the possible side effects from using ergot alkoloids and what should I do about them?

Check with your doctor if you have any of the following side effects:

  • anxiety
  • diarrhea
  • flushing
  • gastric upset
  • nausea
  • restlessness
  • vomiting

Ergot derivatives can have serious side effects. So their use must be limited. Because both ergotamine and DHE cause blood vessels to narrow throughout the body, they can be dangerous for people with diseases of the heart or blood vessels. Contact your doctor immediately if you experience chest pain. Finally, you should not use DHE if you are pregnant since it can harm the fetus.

Frequent use of these medications can cause a form of rebound headache called ergot headache. Ergot headaches are particularly difficult to treat. You can get ergot headaches even if you are only taking small doses of ergotamine or DHE as few as 3 times a week. If you are taking one of these ergot medications, you need to know what the possible side effects are and review them frequently with your doctor.

What drugs may interact with ergot alkoloids and what other health conditions might create a problem?

Talk with your pharmacist and your doctor about possible interactions between ergot alkoloids and other medications or drugs you are taking. Be sure to tell your doctor and pharmacist about all the other medications you are taking as well as about any other medical conditions you have. While you take these medications, be sure to keep your regular appointments with your doctor so that he or she can monitor your progress.

If you have any of the following conditions, you should not use ergot alkaloids:

  • bradycardia
  • coronary artery disease
  • hypertension
  • hyperthyroidism
  • impaired hepatic function such as liver disease or hepatitis
  • infection and fever
  • malnutrition
  • peripheral vascular disease
  • pregnancy and nursing
  • thrombophlebitis, or blood clots

You also should not take this medication if you are older than age 60 or if you are taking beta-blockers.