Marijuana

Marijuana is theworld's most commonly used hallucinogenic drug.This drug comes from a plant called "Cannabissativa." Thechemical in this plant that produces the altered states of consciousnessis called "delta-9 tetrahydrocannabinol" or "THC". Marijuana is usuallysmoked like a cigarette, but it can also be cooked into baked goods likebrownies or cookies or brewed like a tea. THC is also contained in"hashish" (hash) which is the resin from the marijuana plants. Hash isusually smoked in a pipe. Other names for marijuana include: grass, pot,reefer and weed.

Effects of Marijuana on the Nervous System THC acts on "cannabinoid"receptors which are foundon neurons in many places in the brain. These brain areas are involved inmemory (the hippocampus), concentration (cerebral cortex), perception(sensory portions of the cerebral cortex) and movement (the cerebellum).When THC activates cannabinoid receptors, it interfers with the normalfunctioning of these brain areas. In low to medium doses, marijuanacauses: relaxation reduced coordination reduced blood pressure sleepiness disruption in attention an altered sense of time and space...a goodreason not to drive or operate machinery while under theinfluence. In high doses, marijuana can cause: hallucinations delusions impaired memory disorientation. Scientists have known for a long time that THC interacted with cannabinoidreceptors in the brain, but did not know why the brain would have suchreceptors. They thought that the brain must make some kind of substancethat naturally acted on these receptors. In 1992, they found theanswer...anandamide. Anandamide is the brain's ownTHC (just like "endorphin" is the brain's own morphine). Still,scientists are not sure what the function of anandamide is in thenormal brain. The effects of marijuana start as soon as 1-10 minutes after it is takenand can last for 3-4 hours. There is some evidence that the effects of marijuana maylast even longer. Experiments have shown that THC can affect two neurotransmitters: norepinephrine and dopamine. Serotonin and GABA levels may also bealtered.

Whether marijuana can produce addictionis controversial.Alsocontroversial is whether marijuana causes long-term mental abnormalities. Only future research will give us the answers. It is interesting to notethat there are NO documented cases of a fatal overdose produced bymarijuana. However, since there isa high level of tar and other chemicals in marijuana, smoking it issimilar to smoking cigarettes. The lungs get a big dose of chemicals thatincrease the chances of lung problems and cancerlater in life.

Back in 1969, The Journal of theAmerican Medical Association (JAMA, vol. 207, pages 1349-1350, 1969)published a paper that described the psychoactive effects of catnip in people. People who smoked catnip were said to become happy and relaxed. Catnip (from the plant Nepetacataria) DOES cause most cats to act strangely: they roll around,shake their heads, rub against things, and try to get the plant all overtheir bodies. Interestingly, cats are only affected when theysmell it - it has NO EFFECT if they eat it. It appears that catniphas little or no psychoactive effects in people. Actually, in the 1969JAMA paper, the authors mislabeled the pictures of marijuana and catnip.They labeled the pictures of marijuana as catnip and that of catnip asmarijuana.

Take a shorton-line, interactive quiz about amphetamines, cocaine andmarijuana.

Did you know?

Marijuana contains more than 400 differentchemicals.

For more information on marijuana, see: FederalTrafficking Penalties (Marijuana) Just theFactsabout Marijuana - from the Florida Alcohol and Drug AbuseAssociation Marijuana:Facts for Teens - from the National Institute on Drug Abuse Marijuana: Facts for Parents - from the National Institute on Drug Abuse Marijuana FactSheet Marijuana Factsfor Parents Marijuana SpecialReport - from New Scientist MarijuanaUpdate from the National Instituteon Drug Abuse. WhatisMarijuana? What's YourPoison - Marijuana

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