THE ADVERSE EFFECTS OF MARIJUANA

I would like to request you to write about the two most popular
prohibited drugs in the country, marijuana and shabu. What are the
adverse effects of these drugs? Do they cause permanent damage to
health? - Rosita Flores, Sampaloc, Manila

In today's column, I'll discuss marijuana which, no doubt, is the most
widely used illegal drug in the Philippines. The write-up on shabu
will appear in a future column.

Marijuana consists of the dried flowering tops and leaves of the plant
Cannabis sativa. It is used primarily because of its psychoactive
properties. Marijuana can either be eaten or rolled into a joint and
smoked like a cigarette. The latter is the more popular way of taking
the drug because it is the faster way to achieve the drug's effects.

The active constituent of marijuana is tetrahydrocannibol (THC). Its
health and psychological effects are not yet fully understood. There
have been many well-controlled, conclusive, scientific studies about
the drug using animal subjects, but most of the studies involving
humans have given rise to inconclusive and sometimes equivocal
results. At any rate, enough reliable data is available to identify
most of the effects (proven and possible) of the drug.

Most people who take marijuana become "high." In this "pleasant and
desirable" state - which is attained soon after smoking a joint -
their heart rate increases and they become relaxed and euphoric. Some
become unusually talkative and prone to laughter. Many experience
perceptual alteration, time distortion and intensification of ordinary
sensory experiences such as watching films and listening to music.

Occasionally, however, marijuana use leads to a "bad trip," an
unpleasant state characterized by anxiety and panic reactions. If
large doses are taken, the "bad trip" can include confusion, amnesia,
delusions and hallucinations. "Bad trips" are more common among
inexperienced users although even heavy users experience them
occasionally.

However, regardless of whether he/she gets a "high" or a "bad trip," a
person under the influence of marijuana experiences impairment of
short-term memory, motor skills and reaction time. This simply means
he/she is at risk of getting involved in an accident if he drives or
operates a piece of machinery. This risk is probably not worse than
the risk one has when driving or operating machinery while under the
influence of liquor. But a combination of drug and alcohol is,
definitely, deadly.

Acute marijuana toxicity occurs very rarely. There have been no
reported deaths yet from THC poisoning.

Occasional marijuana use probably does not lead to long-term health
problems, but habitual or chronic marijuana use does. (Note: some of these
health problems are irreversible). Chronic marijuana smoking leads to
chronic bronchitis. In addition, marijuana smoke may be carcinogenic
(cancer-producing), it may increase the risk of cancers of the mouth,
pharynx, esophagus and lungs. Marijuana may impair the production of male
sperm and disrupt the female cycle.

Some studies have suggested that marijuana use during pregnancy
results in babies with low birthweights, but the risk of birth defects
is probably nil. Children of women who use marijuana while pregnant
have an increase risk of developing leukemia, and a couple of other
cancers. Likewise, at ages four to nine years they have been found to
have attention, memory and intellectual problems.

Chronic marijuana users are also at risk of developing memory,
attention and intellectual impairment, but at a degree that is
probably much less than those experienced by alcoholics. They also
develop tolerance to the drug, which means they need to take more and
more to experience the effects they want. About 10 percent of heavy
marijuana users develop dependence - similar to that seen among
alcoholics - on the substance.

Chronic marijuana users are at risk of becoming schizophrenic
(psychotic). This is especially true among those who have a family
history of psychosis.

Finally, perhaps the most insidious effect of marijuana lies in the
fact that many chronic users eventually graduate to using "harder"
illegal drugs.