C. purpurea has at least three races or varieties, which differ in their host specificity:[6] An ergot kernel, called a sclerotium, develops when a spore of fungal species of the genus Claviceps infects a floret of flowering grass or cereal.

When a mature sclerotium drops to the ground, the fungus remains dormant until proper conditions (such as the onset of spring or a rain period) trigger its fruiting phase.

The Hospital Brothers of St. Anthony, an order of monks established in 1095, specialized in treating ergotism victims[14] with balms containing tranquilizing and circulation-stimulating plant extracts.

[16] The second type of ergotism is marked by violent burning, absent peripheral pulses and shooting pain of the poorly vascularized distal organs, such as the fingers and toes,[16] and are caused by effects of ergot alkaloids on the vascular system due to vasoconstriction, sometimes leading to gangrene and loss of limbs due to severely restricted blood circulation.

[11][12] Other symptoms include strong uterine contractions, nausea, seizures, high fever, vomiting, loss of muscle strength and unconsciousness.

[17] Klotz offers a detailed overview of the toxicities in mammalian livestock, stating that the activities are attributable to antagonism or agonism of neurotransmitters, including dopamine, serotonin and norepinephrine.

Reduced serum prolactin is associated with various reproductive problems in cattle, and especially in horses, including agalactia and poor conception, and late-term losses of foals and sometimes mares due to dystocia and thickened placentas.

[10] The January 4, 2007 issue of the New England Journal of Medicine includes a paper that documents a British study of more than 11,000 Parkinson's disease patients.

The study found that two ergot-derived drugs, pergolide and cabergoline, commonly used to treat Parkinson's Disease may increase the risk of leaky heart valves by up to 700%.

"[26] Radulf Glaber described an ailment he called "hidden fire," or ignus ocultus, in which a burning of the limb is followed by its separation from the body, often consuming the victim in one night.

[27] In 1722, the Russian Tsar Peter the Great was thwarted in his campaign against the Ottoman Empire as his army, traveling down the Terek steppe, was struck by ergotism and was forced to retreat in order to find edible grains.

A diary entry from the time notes that as soon as people ate the poisoned bread, they became dizzy, with such strong nerve contractions that those who did not die on the first day found their hands and feet falling off, akin to frostbite.

[28] Saint Anthony was a 3rd Century Egyptian ascetic who lived by the Red Sea and was known for long fasting in which he confronted terrible visions and temptations sent from the Devil.

[26] These hagiotherapeutic centers were the first specialized European medical welfare systems, and the friars of the order were knowledgeable about treatment of ergotism and the horrifying effects of the poison.

[29] The sufferers would receive ergot-free meals, wines containing vasodilating and analgesic herbs, and applications of Antonites-balsam, which was the first transdermal therapeutic system (TTS) in medical history.

[29] After 1130, the monks were no longer permitted to perform operations, and so barber surgeons were employed to remove gangrenous limbs and treat open sores.

[29] An important aspect to the Order of St. Anthony's treatment practices was the exclusion of rye bread and other ergot-containing edibles, which halted the progression of ergotism.

[27] The trunk of the body remained relatively untouched by the disease until its final stages, and the victims, not understanding the cause of their ailment, would continue to imbibe ergot-laden food for weeks until the condition reached their digestive system.

She had told him that if uterine contractions were too weak in the expulsion stage of childbirth, she and her mother gave peeled ergot in an amount of the filling of a thimble dispersed in water, wine or broth.

[33] The French physician Jean-Baptiste Desgranges (1751–1831) published in 1818, that in 1777 he had met midwives in Lyon, who successfully treated feeble uterine contractions by administering the powder of ergot.

[34] In the United States, in 1807 Dr. John Stearns of Saratoga County, New York wrote to a friend that he had used, over several years, a pulvis parturiens with complete success in patients with "lingering parturitation".

[35] In 1813, Dr. Oliver Prescott (1762–1827) of Newburyport, Massachusetts published a dissertation "on the natural history and medical effects of the secale cornutum", in which he described and analysed the experience he had gathered over five years while using ergot in cases of poor uterine action in the second stage of labour in childbirth.

[38] Low to very low evidence from clinical trials suggests that prophylactic use of ergot alkaloids, administered by intravenous (IV) or intramuscular (IM) in the third stage of labor, may reduce blood loss and may reduce the risk of moderate to severe hemorrhage following delivery, however this medication may also be associated with higher blood pressure and higher pain.

Not only did it constrict the uterus, ergot had the ability to increase or decrease blood pressure, induce hypothermia and emesis, and influence pituitary hormone secretions.

[16][41][42] An article appearing in the July 23, 1881 edition of Scientific American entitled "A New Exhilarating Substance" denotes cases of euphoria upon consuming tincture of ergot of rye, particularly when mixed with phosphate of soda and sweetened water.

[43] British author John Grigsby contends that the presence of ergot in the stomachs of some of the so-called 'bog-bodies' (Iron Age human remains from peat bogs of northeast Europe, such as the Tollund Man) is indicative of use of Claviceps purpurea in ritual drinks in a prehistoric fertility cult akin to the Greek Eleusinian Mysteries.

[44] Linnda R. Caporael posited in 1976 that the hysterical symptoms of young women that had spurred the Salem witch trials had been the result of consuming ergot-tainted rye.

[47] Mankind has known about Claviceps purpurea for a long time, and its appearance has been linked to extremely cold winters that were followed by rainy summers.

[citation needed] Symptoms of infection by C. africana include the secretion of honeydew (a fluid with high concentrates of sugar and conidia), which attracts insects like flies, beetles and wasps that feed on it.

The bees then create a honey called fic'e (Paraguayan Makai Indian language), which is infused with secretions from the plants and has a pungent aroma.