ABSTRACT
Marijuana is a complex substance with many potential physical and neuropsychiatric adverse effects. Acute physical effects include tachycardia, decreased task performance, and reduced cerebral blood flow. These effects may be particularly dangerous if the user is driving a car, operating machinery, or has certain pre-existing medical problems (such as cardiovascular disease). Acute neuropsychiatric effects may include paranoia, changes in libido, altered time and sensory perceptions, and others. Chronic marijuana use may lead to adverse effects on the respiratory system (due to tar, carbon monoxide, carcinogens and other chemicals), reproduction system, motivation, memory and other systems. Chemical dependence to cannabinoids may insidiously develop and marijuana use can be a “gate way” to use of other substances of potential abuse. Although human studies on marijuana have many limitations, adverse effects of marijuana is of considerable clinical and social importance.
