How to go old-school psycho: St. Anthony's Fire
On the wall of a simple Romanesque church in the tiny French village of Lavardin, there is a strange fresco. It depicts the figure of an uncannily calm St. Anthony ministering to a horde of writhing, sufferers of what is today known as "St. Anthony's Fire." Anthony was a hermetic monk who lived in third century Egypt, and was known to suffer great psychological trials, regarded as assaults on him by Satan. These included horrific visions, hallucinations and frightening voices. The psychological condition was named when, in another remote French village in 1151, hundreds of people went mad. They had hallucinations, writhed in agony in their beds, vomited, ran crazily in the streets and suffered terrible burning sensations in their limbs. It was eventually discovered, however, that rather than being tortured by the Devil, the townspeople had consumed bread tainted by a fungus that grows on rye grass, called ergot. Check out The Temptation of St. Anthony, and get the skinny on ergot, after the jump:
Ergot, according to Medicinenet, "contains a chemical called ergotamine that makes the sufferers go berserk and causes gangrene of the hands and feet due to constriction of blood supply to the extremities. If it is not treated (and this was not possible in the Middle Ages), victims had the sensation of being burned at the stake, before their fingers, toes, hands and feet dropped off. In moderate doses, ergotamine causes the contraction of smooth muscle fibers, such as those in small arteries. Ergotamine has been used to control hemorrhage (bleeding) and to promote contraction of the uterus during childbirth. It is also used to treat migraine headaches (its major use today). But in large doses, ergotamine paralyzes the motor nerve endings of the sympathetic nervous system."
In other words, this happens: