Ergotism—Saint Anthony’s Fire—Food Poisoning

By Dominique Jacquin via Wikimedia Commons
Claviceps purpurea on barley. By Dominique Jacquin [Public domain], via Wikimedia Commons
Burning extremities; lost limbs; stinking, erupting pustles; delerium and death—ergotism is a form of food poisoning caused by fungal growth on grain. Among the effects are hallucinations and the alkaloids within are related to the psychoactive drug LSD.

The cause of ergot poisonings was not known in Europe for almost a thousand years. From its rise before the end of the first millennium until the identification of the ergot fungus as the cause of bread poisonings in the seventeenth century, it killed tens of thousands at a time in waves of epidemics.

Ergot is a group of Claviceps fungi that grows in the field in ears of rye, and to a lesser extent, barley and wheat, among other grasses. It was a long-known thing in some parts of the world where rye had long been cultivated: ergot may have been used deliberately among prehistoric cults, and for the psychoactive effects 4,000 years ago in the Greek Eleusinian mystery cult. It was used in China as a medication before 1000 BC and in the Middle East almost a thousand years before that. But rye was only introduced into Europe in the Middle Ages, and Europeans had no experience with the ergot.

In one stage of its growth, it sticks prominently out of an ear of grain. Back then, that purple-black growth on some ears of grain was so common it was assumed to be part of the plant. When the winter was cold and the summer was wet, there was more of it. Black, elongated and shriveled, it was clearly not a normal seed, and one could see an ergot amidst lighter-coloured grains, and pick it out. But since Europeans didn’t know it caused problems, it might be left in low quality grains. When ergot-infested grain was ground into flour, baked into bread, and eaten by many people, ergotism occurred in epidemics.

Ergot symptoms come in two forms, depending on the alkaloids in the ergot. One includes painful spasms, itching, psychosis (including delirium and hallucinations), nausea and vomiting, and spontaneous abortions. Those are the “convulsive” central nervous system effects of severe poisoning, and was (apparently) more common in Germany.

The “gangrenous” form (caused by blood vessel constriction) includes skin swelling, blistering, burning pain, numbness, and gangrene. Limbs could dry and fall off, and death could result. It was more common in France.

Advanced ergotism. By Matthias Grünewald, about 1515.
Advanced ergotism. By Matthias Grünewald, about 1515.

It would make famine worse. We don’t think much about famine these days, but so much could go wrong back when your sole food source grew around you: bad weather meant a poor harvest which meant that by early summer of the next year everyone would be out of food and the next harvest wouldn’t be ready yet. Bad weather favoured the ergot fungus, and ergot infections increased with cold winters and wet summers, the same conditions that also ruined crops and harvests, and stretched the resources and resilience of people. Growing on many types of grass, ergotism also affects cattle, pigs, sheep, and poultry, causing weight loss, abortions, and other symptoms, including gangrene and death, and is passed in mother’s milk.

When people were reduced to eating anything they could, that meant literally scraping the bottom of the barrel, eating poorest quality grain, and flour bulked up with roadside adulterants.

Full section of the outer wing of the Isenheim Altarpiece, depicting The Temptation of St Anthony. Matthias Grünewald, about 1515.
Full section of the outer wing of the Isenheim Altarpiece, depicting The Temptation of St Anthony. Ergotism lower left. Matthias Grünewald, about 1515.

The condition was known as Saint Anthony’s Fire, with the “Fire” part referring to the intense burning in the hands and feet. Ergotism was actually one of the causes of a group of symptoms known as “Saint Anthony’s Fire.”[1]

The Hospital Brothers of St. Anthony was founded in 1095 by a French nobleman whose son (we are told) was cured by relics of Saint Anthony. Monks of the brotherhood were devoted to treating victims of the condition. In 1676 it was shown that ergot was the cause of bread poisoning, which reduced the incidence as it was now kept out of flour. Ergot was subsequently used as a medicine in Europe for hundreds of years up until the 1930s to induce abortions or childbirth by contractions of the uterus, and it’s still used to treat migraines.

Ergotism still occurs today, but is controlled by careful monitoring of rye, which is the main commercial host of ergot. It’s probably still in your bread. Flour is limited in the maximum amount of ergot contamination legally allowed. With the synthesis of LSD from ergot, came the separation of a psychoactive material from the dangerous consequences of ergot consumption. Our relatively benign attitude to LSD can’t be extended to ergot. It appears to be too dangerous and unpleasant to be an historic entheogen without some unknown and un-heard-of preparation.

A Few References:

Schiff, P. L. (2006). Ergot and Its Alkaloids. American Journal of Pharmaceutical Education, 70(5), 98.

Ergot of rye. Schumann, G.L. 2000. Ergot. The Plant Health Instructor. DOI: 10.1094/PHI-I-2000-1016-01. Updated 2005.

Ergot of Rye – I: Introduction and History. (Web)


  1. “St Anthony’s Fire” actually included similar conditions which we now recognize as having other causes – such as shingles and erysipelas. []

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