The usual course of an acute case of poisoning is a feeling of dryness in the nose and throat, difficulty of swallowing, faintness, and there is often vomiting; the pulse is quickened; there is first cerebral excitement, followed usually by great mental depression. Occasionally there is an eruption on the skin. Hyperæsthesia of the skin is followed by great diminution of sensation, the pupils, as before stated, are dilated, the eyes protruding, the eyelids wide open, the face is pale, and the perspiration profuse. Convulsions and paralysis may terminate the scene. Death takes place from paralysis of the breathing centre; therefore the heart beats after the cessation of respiration. As an antidote, nitrite of amyl has apparently been used with success.
There is a form of chronic poisoning produced from the taking of small doses of cocaine daily. The symptoms are very various, and are referable to disturbance of the digestive organs, and to the effect on the nervous system. The patients become extremely emaciated, and it seems to produce a special form of mania.
§ 418. Post-mortem Appearances.—The appearances found in acute cases of poisoning have been hyperæmia of the liver, spleen, and kidneys, as well as of the brain and spinal cord.
In the experimental poisoning of mice with cocaine Ehrlich[464] found a considerable enlargement of the liver.
[464] Deutsche med. Wochens., 1890, No. 32.
§ 419. Fatal Dose.—The fatal dose, according to Mannheim,[465] must be considered as about 1 grm. (15·4 grains); the smallest dose known to have been fatal is 0·08 grm. (1·2 grain) for an adult, and 0·05 grm. (0·7 grain) for a child.
[465] Deutsch. Arch. f. klin. Med., Bd. viii., 1891, 380.