ERGOT, a drug consisting of the sclerotium (or hard resting condition) of a fungus, Claviceps purpurea, parasitic on the pistils of many grasses, but obtained almost exclusively from rye. In the ear of rye infected with ergot there exudes a sweet, yellowish mucus, which after a time disappears. The ear loses its starch and ceases to grow, and its ovaries become permeated by the mycelium of the fungus which forms the sclerotium in autumn.
The drug consists of curved dark-purple grains -4 to 12in. long, and 1 to 4 lines broad, having two lateral furrows, a rancid taste, and fishy odour, intensified by potash solution.
The active principle of ergot is the alkaloid ergotine which is given intramuscularly. Other ingredients are a fixed oil, present to the extent of 3o%, ergotinic acid, a glucoside, trimethylamine, which gives the drug its unpleasant odour, and sphacelinic acid, a non-nitrogenous resinoid body.
Ergot has no external action. Given internally the drug itself and ergotine cause contraction of unstriped muscle generally but act particularly on that of the arterioles, bronchioles and uterus. By its action on the blood-vessels it raises blood pressure and is locally and remotely haemostatic. By its action on the bronchioles it may induce a condition resembling asthma. With regard to uterine muscle ergot is the most powerful known stimu lant of the pregnant uterus. The action is a double one. At least four of its constituents act directly on the muscular fibre of the uterus, whilst the ergotine acts through the nerves. Of great prac tical importance is the fact that ergotine causes rhythmic contrac tions such as naturally occur, whilst the sphacelinic acid produces a tonic contraction of the uterus, which is unnatural and en dangers the life of the foetus.
Chronic poisoning, or ergotism, used frequently to occur amongst the poor fed on rye infected with the Claviceps. There were two types of ergotism. In the gangrenous form various parts of the body underwent gangrene from arrest of their blood supply. In the spasmodic form the symptoms were nervous. The disease began with cutaneous itching, tingling and formication, which gave place to loss of cutaneous sensation, first observed in the extremities. Amblyopia, deafness and mental failure also occurred. With weakness of the voluntary muscles went inter mittent spasms which weakened the patient and ultimately led to death by implicating the respiratory muscles. The last known "epidemic" of ergotism occurred in Lorraine and Burgundy in the year 1816, but sporadic cases are still met with.