The coca tree Erythroxylon coca is cultivated in South America. The dried leaves have a bitter, aromatic taste, and an odor like tea. They are extensively used by the natives, who chew them as a stimulant during hard labor, scarcity of food, etc. They contain an alkaloid, cocaine, the active principle.
Coca in small doses is stimulant, tonic, and restorative. It strengthens the heart and respirations, raises arterial tension, increases the supply of blood to the brain, producing wakefulness, and lessens the sensations of hunger and fatigue. It has diuretic action, and decreases the amount of urea by checking tissue waste. Under the influence of coca, or cocaine, the skin is flushed, the circulation excited, and a sense of heat and perspiration result.
Cocaine in solution has decided action as a local anaesthetic. If applied to a mucous surface, as the tongue or conjunctiva, or if given hypodermically, it quickly paralyzes the sensory nerves and contracts the small vessels, producing a state of local anaemia and anaesthesia, which lasts for fifteen minutes, or longer, in proportion to the strength of the application. It is often used in this way for minor surgical operations (amputation of a finger; opening of an abscess, etc.). Applied to the eye it causes dilatation of the pupil, which begins in a few minutes, reaches its height in about an hour, and returns to the normal state in twenty-four hours.
Overdoses weaken the heart and the pulse becomes small, rapid, and intermittent. There is a feeling of tightness about the chest; the respirations are slow and shallow, and the skin cold and clammy. There are sometimes hallucinations and delirium. Poisonous doses paralyze the sensory nerves and the respiratory centre. This has been shown by experiments on animals, no fatal cases in man being known.
Five grains taken by mouth have caused alarming symptoms: loss of sight, nausea, incoherent speech, cyanosis, rapid intermittent pulse, and a feeling of suffocation. In treating severe depression from the use of cocaine, alcohol, opium, and nitrite of amyl are used as antagonists.
The habit of constantly taking large doses of cocaine is readily formed, and produces emaciation, insomnia, and disordered digestion. If carried to excess the intellect is weakened, even to insanity. The victim has an uncertain gait, an apathetic air, eyes sunken and surrounded with a deep purple ring, trembling lips, teeth crusted with a greenish deposit, a peculiar blackness around the corners of the mouth, and excessive fetor of the breath. Ascites sometimes appears, and death may result from a general wasting of the vital powers.
Coca is used as an ingredient in many "soft" drinks, as appears evident in their names. This constitutes an insidious danger to the young, in promoting a craving for the drug effects, a danger which has been emphasized by reliable writers.
Coca must not be confused with cocoa, the useful beverage made from the seeds of Theobroma Cacao, the chocolate tree; however, the chocolate, tea, and coffee plants are related to one another and also to the Coca plant and the Kola plant, as well as to several others containing similarly stimulating principles. From cocaine, the active alkaloid of coca, is made the only official preparation of this drug:
The average dose is gr. 1/4-0.015 Gm.