MARIJUANA. drug composed of the dried inflorescences of Cannabis sativa, the common hemp (q.v.), native to Asia and naturalized throughout tropical and temperate regions of the world. The inflorescences contain a hypnotic resin, called cannabin, and an essential oil. The drug is smoked by addicts in the form of cigarettes. Marijuana has an extensive effect on the nervous system, but its habit-forming properties, are a matter of controversy among physicians. Moderate or small doses of the drug are stimulant in the early stages following administration, but act as a depressant in later stages. Marijuana causes dilation of the pupils of the eyes, general depression of the sense of touch, and reduction of pain. It also tends to cause a semiconscious mental condition resulting in loss of power to judge time and distance, and produces a feeling of well-being which often impels the user to perform senseless acts. In later stages, the drug produces drowsiness, followed by sleep. Moderate amounts of marijuana do not produce unpleasant aftereffects. Excessive amounts of marijuana are rarely fatal, but may cause semipermanent depression of respiratory and circulatory functions. Compare CANNABIS.