The Changing Drug Culture: Medical and Recreational Marijuana.

: The major psychoactive compounds in marijuana (cannabis) are cannabinoids, the most significant of which is delta-9-tetrahydrocannabinol. There are also two synthetic pharmaceutical cannabinoids, nabilone and dronabinol, available by prescription in the United States. The use of marijuana has increased in the United States with passage of medical marijuana laws in many states and legalization of recreational marijuana use in several states. In addition, the potency of marijuana has increased in recent years. Marijuana has been used for a variety of medical purposes, including management of nausea and vomiting, appetite and immunologic stimulation in patients with HIV infection and AIDS, glaucoma, neurologic disorders, and pain relief. Studies on the benefits of marijuana as a treatment for various conditions have been inconsistent, except for those on pain management. Marijuana has adverse effects, and has been associated with driving impairment, psychosis, dependence and withdrawal syndromes, hyperemesis, acute cardiac events, some cancers, and impaired lung function. As with studies on the benefits of marijuana, studies of adverse effects have yielded inconsistent results. Except for impaired driving and the occurrence of dependence and withdrawal syndromes, the adverse effects of marijuana use have not been fully studied.