What is marijuana (pot)?

Marijuana (pot) is by far the most commonly used illegal drug, although in recent years it has become legal in some states, either solely for medical use in some states or for medical and recreational use in others. It may also be the most insidious drug, because most people don't realize how dangerous it is. Since the 1990s, most marijuana contains significantly more THC (delta-9-tetrahydrocannabinol, the active ingredient in the drug) than marijuana used in the 1960s and 1970s. Thus, the effects of smoking part of a single 21st-century marijuana cigarette produces more profound and debilitating effects than smoking several marijuana cigarettes in the 1970s would have.

Marijuana is usually smoked, either in a pipe or a loosely rolled cigarette known as a "joint." Joints are infrequently (and usually unknown to the user) laced with the potent hallucinogen PCP or other drugs that substantially alter the effects of marijuana. Marijuana can also be brewed into tea or mixed in baked products like cookies or brownies.

The effects of smoking are usually felt in a few minutes and peak in 10 to 30 minutes. They include dry mouth and throat, increased heart rate, impaired coordination and balance, delayed reaction time and diminished short-term memory. Marijuana can impair driving and lead to accidents, and its effects may be worse in combination with alcohol. Larger doses can cause more intense reactions such as paranoia.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.