Ergotism
Ergotism is the effect of long term ergot poisoning, traditionally due to the ingestion of the alkaloids produced by the Claviceps purpurea fungus that infects rye and other cereals, and more recently by the action of a number of ergoline-based drugs. It is also known as ergotoxicosis, ergot poisoning and Saint Anthony's Fire. Ergot poisoning is a proposed explanation of bewitchment.
Signs and symptoms
The symptoms can be roughly divided into convulsive symptoms and gangrenous symptoms.
Convulsive
Convulsive symptoms include painful seizures and spasms, diarrhea, paresthesias, itching, mental effects including mania or psychosis, headaches, nausea and vomiting. Usually the gastrointestinal effects precede central nervous system effects.
Gangrenous
The dry gangrene is a result of vasoconstriction induced by the ergotamine-ergocristine alkaloids of the fungus. It affects the more poorly vascularized distal structures, such as the fingers and toes. Symptoms include desquamation or peeling, weak peripheral pulses, loss of peripheral sensation, edema and ultimately the death and loss of affected tissues. Vasoconstriction is treated with vasodilators.