COCAINE
Cocaine is an alkaloid obtained from the Erythroxylon Coca. It produces a paralysing effect upon the endings of sensory nerves, and is used as a local anæsthetic. When absorbed into the blood it paralyses the vagus and causes increased rapidity of the pulse. Applied to the eye it causes dilatation of the pupil. It first has a stimulating action on the centres of the brain and spinal cord, finally paralysing them. It produces death by paralysis of respiration, according to Mosso, by causing tetanus of the respiratory muscles.
Symptoms.—The symptoms produced are pallor, cyanosis, faintness, and cold sweats, pain in the precordial region, rapid pulse, intermittent heart beat, laboured respiration. The pupils are dilated. Speech becomes incoherent, there may be trismus of the jaws, the ideas are confused, and there may be delirium. Tetanic spasms of muscles may occur, and convulsions, also loss of consciousness.
Chronic poisoning, following the cocaine habit, produces a long series of symptoms which are manifestations of mental and physical degeneration, which in extreme cases may pass on to insanity, with hallucinations and delusions.
Fatal Dose.—Half a grain injected into the gum of an adult has caused alarming symptoms, and two-thirds of a grain has caused death. Recovery has taken place after forty-three grains were taken by the mouth.
Fatal Period.—Death has occurred in twenty minutes after three and a half grains by hypodermic injection.
Chemical Analysis.—The alkaloid may be separated from the stomach contents or viscera by the usual procedure for extraction of alkaloids.
1. On the addition of strong nitric acid and evaporating to dryness, the residue when treated with alcoholic solution of potash gives off an odour like peppermint or meadow-sweet.
2. Goeldner‘s Test.—Strong sulphuric acid and resorcin when mixed with cocaine gives a blue colour, changing to rose-pink on addition of caustic potash. Goeldner considers this a reaction peculiar to cocaine.
3. Metzer‘s Test.—If a few drops of a 5 per cent. solution of chromic acid in water be added to a solution of cocaine hydrochloride, each drop gives a yellow precipitate which redissolves. The addition of strong hydrochloric acid produces a yellow precipitate of chromate of cocaine. Metzer considers this reaction peculiar to cocaine.
4. When applied to the tongue or lips a feeling of numbness is produced; it is rendered more effectual if a solution of sodium bicarbonate be first applied to the mucous membrane.
Treatment.—Wash out the stomach and encourage vomiting. Stimulants and ammonia should be given freely, and if convulsions occur chloroform should be inhaled. Tannic acid or gallic acid in thirty-grain doses have been recommended, also iodine one grain with potassium iodide ten grains, in a wine-glassful of water between the stomach-washing or emesis. Oxygen inhalations and artificial respiration may be resorted to in failure of the respiration.