reefer, pot, herb, ganja, grass, old man, blanche,
weed, sinsemilla, bhang, dagga, smoke, kind. There are a wide variety of
different user experiences with marijuana, depending upon the potency of the
drug taken. In general, smoking marijuana relaxes the user and elevates her
mood. Users can shift between contemplation and hilarity depending on their
Marijuana is the Indian hempplant, Cannabis
sativa, or the crude drug composed of its leaves and flowers. It is usually
dried and crushed and put into pipes or formed into cigarettes (reefers, or
joints) for smoking. The drug--known by a variety of other names, including
pot, tea, grass, and weed--can also be added to foods and beverages. Marijuana
varies in potency, depending on where and how it is grown, prepared for use, or
stored. The active ingredient, tetrahydrocannabinol (THC), is present in all
parts of both the male and female plants but is most concentrated in the resin
(cannabin) in the flowering tops of the female.
Marijuana acts on specific cannabinoid receptors in the
brain. Psychological effects tend to be predominant; the user commonly
experiences a mild euphoria. Alterations in vision and judgment result in
distortions of time and space. Acute intoxication may occasionally induce
visual hallucinations, anxiety, depression, extreme variability of mood,
paranoid reactions, and psychoses lasting from four to six hours.
Physical effects include reddening of the eyes, dryness of
the mouth and throat, moderate increase in the rapidity of the heartbeat,
tightness of the chest (if the drug is smoked), drowsiness, unsteadiness, and
In the late 1980s researchers discovered a receptor for
THC and THC-related chemicals in the brains of certain mammals, including
humans. This finding indicated that the brain naturally produces a THC-like
substance that may perform some of the same functions that THC does. Such a
substance subsequently was found and named anandamide, from "ananda," the
Sanskrit word for bliss.
When marijuana is smoked, the blood supply of the lungs absorb the THC. The
blood then moves to the heart where it increases the heart rate. If the
marijuana is eaten, less THC gets to the brain and takes longer to get there.
The amount of THC in the body would be less for the amount of marijuana eaten,
however, since it takes longer to work, users are likely to consume more
marijuana than they would normally smoke. High levels of THC can cause
hallucinogen-like experiences that smokers are less likely to feel.
Chronic use does not establish physical dependence, nor,
upon withdrawal, does the regular user suffer extreme physical discomfort (such
as that associated with narcotics), but its use may be psychologically
habituating. Since THC remains in the body, it has been found to have residual
effects on cognitive functions (including memory) up to 48 hours after smoking.
However, there is no evidence that these effects last longer than two days.
Chronic marijuana smokers can experience lung problems and generally do not
produce as much airflow as nonsmokers do.
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