Ergot is dried sclerotium of a fungus called Claviceps.purpurea developing commonly in the ovary of Rye plant-Secale.cereale or less commonly on other cereals like wheat, oats etc. Ergot has been known in olden days as an extremely toxic pathogen infecting the grains, thereby decreasing their quality. In the middle ages in various European countries, the contamination of Rye plants with Ergot was responsible for the outbreak of a disease having symptoms like severe itching, redness and pain in the extremities followed by severe convulsions, unconsciousness and death. Owing to these symptoms, in a layman’s language the disease was called as “St.Antony’s Fire”. Later it was recognized as “Ergotism”.The medicinal uses of ergot were discovered in the 16th century; however its use in Obstetrics became widespread in the 19th century when it was included in official book of London (London Pharmacopoeia).The most important producers of ergot are Czechoslovakia, Switzerland and Hungary.
The beneficial and toxic properties of ergot are due to the presence of an important class of compounds called indole alkaloids. These compounds represent the largest group of nitrogenous metabolites having complex chemical structures synthesized in fungus and are related to amino acids present in the living organisms. Ergot alkaloids are of two types (1) water soluble like ergometrine (ergonovine) and (2) water insoluble like ergotamine, ergocristine, ergocryptine etc. These alkaloids have structural similarity to some endogenous chemicals present in the body namely noradrenalin, serotonin, dopamine which have varied effect on smooth muscles like uterus, some parts of brain, blood vessels etc. The alkaloids thus produce their effect by either promoting or blocking the effects of these chemicals. These alkaloids have unique stimulatory action specifically on uterine wall due to which they are mainly used in obstetrics. Their analgesic property is explored in migraine.
Health Benefits of Ergot
Important uses of ergot alkaloids include – Obstetrics such as abortificient, oxytocic, in post partum hemorrhage and in Migraine.
Ergot for obstetric purpose
Oxytocin is a natural hormone in females which causes contraction of uterus and induces labor at the time of delivery. Ergot alkaloids find their use as oxytocic by mimicking this effect of Oxytocin. They directly stimulate the contractions of uterine wall muscles. So they are used in labor to aid in delivery and reducing the post partum hemorrhage PPH (loss of more than 500ml of blood post delivery due to failure of uterine muscles to contract) . Bleeding is primarily reduced because of vasoconstrictor (narrowing of vessel lumen) effects. They have been preferred over other oxytocic drugs like misoprostol for PPH. Ergonovine marketed as its maleate salt and methylergonovine have been approved by FDA for routine management of postpartum uterine atony and hemorrhage and in prophylaxis of abortion cases where complications include excessive bleeding.
These are generally injected in the final stages of labor or immediately following childbirth. Ergot alkaloids are also valuable in cesarean operations as these persons are at greater risk of PPH. Side effects may include rise in blood pressure and tetanic contractions. But these can be reduced when drugs are given at small doses. Larger doses on other hand produce prolonged contractions which may precipitate the side effects. Also you should not use ergot preparations for inducing labor or in cases of threatened abortion or during pregnancy.
Ergot in migraine
Important properties of ergot alkaloids useful for migraine therapy are (i) potent vasoconstriction property (ii) stimulating the release of serotonin, a chemical needed to transmit signals in brain (iii) anti-inflammatory effect. , Migraine is characterized by severe throbbing unilateral headache caused due to sustained dilation of blood vessels in brain. Different alkaloids of ergot cause vessel contraction to a varying degree. For example ergotamine has very potent vasoconstriction effect and hence cannot be used for obstetrics. So its properties are exploited in treatment of acute attacks of migraine where it reverses the dilatation of cranial vessels and provides relief from severe pain. Ergotamine tartrate has FDA (Food and Drug Association, US) indication for therapy of moderate to severe migraine attacks where it not only acts as analgesic but also prevents further neurogenic inflammation (swelling in brain). You can take this medicine orally with coffee or tea as caffeine enhances the activity of drug. A number of derivatives of ergot alkaloids are now-a-days preferred for getting immediate relief from migraine pain. Methysergide, a semi-synthetic derivative of lysergic acid found in ergot, is employed in prophylaxis (prevention of disease) of migraine headaches but with proper medical supervision. Another derivative dihydroergotamine have been approved by FDA for cluster headache and acute migraine attacks. You should take the drugs at the very onset of migraine attack. Mild nausea and vomiting may occur due to the drugs stimulating the vomiting centre in brain.
Ergot in treatment of Hormonal disorders.
Ergot alkaloids found wider use in hyperprolactinemia (excessive amount of prolactin hormone in the body).Prolactin is a hormone that promotes development of breast and lactation after delivery. High levels of Prolactin cause development of breast in males, menstrual irregularity infertility and breast cancer in females etc. Synthetic derivatives of ergot alkaloids bromcriptine and cabergoline have been used in such conditions by inhibiting the release of hormone thus suppressing lactation. They are also effective in breast cancers.
Besides, FDA has also approved bromcriptine for treatment of acromegaly (overproduction of growth hormones resulting in enlarged bones, hands, feet etc).
Miscellaneous uses of ergot alkaloids
- A mixture containing equal parts of dihydroergocristine, dihydroergocryptine is used in lowering blood pressure and treating bradycardia particularly in elderly patients.
- Bromcriptine is used in combination with L-dopa for therapy of patients with Parkinson’s disease.
- Lysergic acid diethylamide (LSD), a semi-synthetic derivative is used in Psychiatry for its psychotomimetic action (an agent that produces condition resembling psychosis) but it has abuse potential (hallucinogenic) and so use is generally restricted.
Ergot adverse effects, toxicity and precautions
On taking ergot alkaloids you may suffer from nausea, vomiting, diarrhea, abdominal discomfort, fatigue. These symptoms generally disappear on discontinuing the drugs. But on chronic administration they are extremely harmful and sometimes fatal. Hence prolonged treatment with any of the ergot alkaloids is undesirable. It is recommended that in cases of migraine you should not take the drug for more than six months continuously. You should discontinue your medications and immediately consult your physician if any kind of chest pain or bluish discoloration or pain or tingling in extremities (fingers and toes) is observed.
Ergot alkaloids are contraindicated in heart diseases because narrowing of blood vessels of heart may further worsen the disease. Besides they should not be used if you are suffering from peripheral vascular diseases, sepsis, hypertension, and liver diseases and kidney diseases.
Ergot thus finds its use in many important and challenging clinical conditions like PPH, migraine etc. Just an appropriate medical supervision with controlled use of drugs is necessary to gain the desirable life saving benefits of Ergot.