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Q: Drugs ( Answered,   3 Comments )
Subject: Drugs
Category: Health
Asked by: mmee-ga
List Price: $4.00
Posted: 29 Oct 2002 14:28 PST
Expires: 28 Nov 2002 14:28 PST
Question ID: 92461
What are the negative effects of mariguana use both in the long term
and in the short term, are they permanent and what is the healthiest
way to consume the drug?
Subject: Re: Drugs
Answered By: cobrien-ga on 30 Oct 2002 07:31 PST
Before I begin, can I first say that the following answer is no
substitute for medical opinion. It is for information purposes only.
If you have any concerns about your health, or someone close to you,
please seek proper medical advice.

The list of long-term side effects of marijuana use is not exhaustive
– this is mainly due to the fact that not all the side effects are
known yet. However, research has shown that it is believed there are
several long-term side effects of marijuana use.

The main ones are cancer, problems with the lungs and/or airways, and
damage to the immune system.

This information from the National Institute on Drug Abuse says that
although it is not known for sure that ‘regular’ marijuana use causes
cancer, ‘it is known that marijuana contains some of the same, and
sometimes even more, of the cancer-causing chemicals found in tobacco

Marijuana users may also suffer from more chest colds, wheezing and
run a greater risk of contracting pneumonia than non-smokers. The
information also points out that THC can damage the immune system,
making users more susceptible to infections and illnesses.

In the Know Zone also offers similar information on the long-term
effects of marijuana use; however, it also adds damage to the
reproductive system, emotional and intellectual damage to the list.
Marijuana is also considered to be psychologically addictive.

There is also some belief that using marijuana causes changes in the

The National Institute of Health: 
 “Long-term use of marijuana produces changes in the brain that are
similar to those seen after long-term use of other major drugs of
abuse such as cocaine, heroin, and alcohol. Moreover, these changes
may increase a user's vulnerability to addiction to other abusable
drugs by "priming" the brain to be more easily changed by drugs in the

For additional information, see In the Know Zone:

However, evidence of lasting damage to the brain caused by marijuana
is not conclusive:

“…it is extremely difficult to perform reliable studies of heavy
marijuana users out of the community, because of what scientists call
‘confounding variables’ – external factors that can distort the

“…the safest thing to say at this point is that the jury is still out
on the question of whether long-term marijuana use causes lasting
impairment in brain function”

There have also been reports on the psychiatric effects of cannabis
use – some reports have found that the drug can affect mental health.
A report on states that a study found that cannabis
could cause temporary psychosis.

“…one in six regular cannabis users displayed severe psychotic
symptoms, including hearing voices or irrational feelings of
persecution. Cannabis users were also more likely to develop other
types of mental illness, such as depression.”

The short-term effects of marijuana use are also well documented. The
Greater Dallas Council on Alcohol and Drug Abuse has this information
on its Website:
 “Short-term effects of marijuana include problems with memory and
learning, distorted perception (sights, sounds, time, touch), trouble
with thinking and problem solving, loss of motor coordination,
increased heart rate, and anxiety. These effects are even greater when
other drugs are mixed with marijuana. A user may also experience dry
mouth and throat.”

In the Know Zone lists similar short-term effects of marijuana use,
also adding panic attacks to the list.

Other websites containing information on the short-term effects of
marijuana use include:

The National Institute on Drug Abuse ‘Marijuana: Facts for Teens’

1Uphealth ‘Marijuana Facts’

You also ask if the effects are permanent. This is a question that
really can’t be answered conclusively at the moment. Research is still
ongoing, and it would be irresponsible of me to give you a definitive
answer without mentioning this fact.

However, I have found information on how the drug is retained in the

From the American Council for Drug Education: 
“Most of marijuana’s short-term effects wear off within two or three
hours. The drug itself, however, tends to linger on. THC is a
fat-soluble substance and will accumulate in fatty tissues in the
liver, lungs, testes, and other organs. Two days after smoking
marijuana, one-quarter of the THC content may still be retained. It
will show up in urine tests three days after use, and traces may be
picked up by sensitive blood tests two to four weeks later.”

“Although it has yet to be proven conclusively that heavy marijuana
use can cause irreversible loss of intellectual capacity, animal
studies have shown marijuana-induced structural damage to portions of
the brain essential to memory and learning” has the following information:
“…since marijuana is a highly fat soluble substance, it becomes
absorbed into the body and tends to accumulate, especially with
chronic use. As a result, one session of marijuana smoking can impact
the body and brain for several weeks. Continued use of marijuana will
continue the damage pattern. During the time that marijuana is in your
system and is interfering with your brain's receptors, it is causing
damage that can be long lasting or permanent. On the other hand, your
body and brain will grow healthier and stronger with time once you
stop using marijuana, although all the problems may not disappear

The issue of a ‘healthy’ way of consuming marijuana is a difficult

As a medical drug, it is still undergoing trials, and there are
conflicting reports about how safe it is to use.

This article from the Medical College of Georgia’s Website casts some
doubt on its effectiveness as a treatment for glaucoma, and also
mentions that long-term use can cause ‘emphysema-like’ changes in the

This article, attributed to the Toronto Star, shows concerns raised by
doctors on the use of marijuana as a medical treatment.
“…doctors have been alarmed by the federal government's decision to
allow marijuana for medical purposes, given little scientific evidence
showing its effectiveness. They say they do not even know what dose to
dispense or what to tell patients about risks or benefits.”

If you are looking for a healthy way to take the drug for recreational
use, I can't help – Google Answers’ Terms of Services prevents
researchers from giving information on conducting illegal activities.

Search Terms used

Marijuana and long term effects
Marijuana and short term effects
Marijuana and medical use
Marijuana and permanent effects

I hope this information is of some use to you. If anything about this
answer is unclear, please ask for clarification before rating.
Subject: Re: Drugs
From: tehuti-ga on 29 Oct 2002 15:22 PST
You might want to look at this answer about long term effects
Subject: Re: Drugs
From: moot-ga on 29 Oct 2002 16:02 PST
check out
Subject: Re: Drugs
From: ziffielou-ga on 30 Oct 2002 12:15 PST
You might want to research Marinol ( The Brand used therapeutically)
either online or at a high class medical library, such as the Countway
at Harvard Medical School.

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