MARIJUANA AND MEDICAL SCIENCE

The rhetoric surrounding marijuana, or cannabis sativa, as medicine
ranges from calling it everything from "the killer weed" to "the
miracle drug." Each side in the debate pulls snippets from scientific
studies to confirm or rebut their point of view. One need only review
information provided by groups like the National Organization for
Reform of Marijuana Laws or the White House policy room to see this effect.

The most comprehensive look at the issue to date is Marijuana and
Medicine: Assessing the Science Base, conducted by the U.S. Institute
of Medicine and published in 1999. With minimal research being
conducted in the U.S. on marijuana as medicine, in 2000, the
California Legislature created the University of California's Center
for Medicinal Cannabis Research in San Diego. The center was tasked
to assess the use of cannabis as an alternative for treating specific
medical conditions.

Research is now being conducted in institutions around the world,
trying to unlock the potential medical benefits of compounds called
cannabinoids found in cannabis sativa. A summary of research
published in 2007 is at the end of the article.

One of the spurs to this increased interest was the discovery in the
1990s of special receptors in different areas of the brain, which
respond to cannabinoids. This led to the identification of a
substances created naturally by the body that resemble THC the main
active ingredient in marijuana.

Most people smoke marijuana to get "high." This high provides a
"sense of well-being or euphoria and increased talkativeness and
laughter alternating with periods of introspective dreaminess
followed by lethargy and sleepiness. A characteristic feature of a
marijuana 'high' is a distortion in the sense of time associated with
deficits in short-term memory and learning. A marijuana smoker
typically has a sense of enhanced physical and emotional sensitivity,
including a feeling of greater interpersonal closeness. The most
obvious behavioral abnormality displayed by someone under the
influence of marijuana is difficulty in carrying on an intelligible
conversation, perhaps because of an inability to remember what was
just said even a few words earlier," according to the 1999 IOM study.

"Although marijuana smoke delivers THC and other cannabinoids to the
body, it also delivers harmful substances, including most of those
found in tobacco smoke. In addition, plants contain a variable
mixture of biologically active compounds and cannot be expected to
provide a precisely defined drug effect. For those reasons, there is
little future in smoked marijuana as a medically approved
medication," concluded the IOM study.

The study further concluded that for some patients, such as the
terminally ill, if marijuana would possibly benefit the patient, the
long-term risk was "not of great concern."

For other patients, the study advised that physicians could consider
marijuana for a narrow range of short term health issues such as AIDs
wasting diseases, severe nausea and vomiting associated with cancer
and its treatment and relief of neuropathic pain. While the study
concluded marijuana had the potential in some patients to relieve the
symptoms, the study also suggested stringent guidelines for
physicians recommending marijuana to their patients.

The prescription guidelines were established to relieve symptoms
considered debilitating such as intractable pain or vomiting. The key
points were for marijuana to be tried after all approved medications
had failed to provide relief; the prescription be for less than six
months; a follow up program be implemented to assess effectiveness;
and the recommendation be supported by an oversight review board
within the hospital or clinic.

For chronic debilitating conditions such as pain or AIDS wasting, the
IOM study recognized that the issues of long-term medical use of
marijuana was more complex. Patients who had exhausted the other
available medical options could not be reasonably expected to wait
until some time in the unknown future for someone to isolate and
synthesize the precise cannabinoid drug cocktail that provided the
best benefit or to develop a "nonsmoked rapid-onset cannabinoid drug
delivery system."

Since the IOM study, a number of vaporizers, which claim to provide
the user with the benefit of marijuana without the hazard of the
smoke, have been developed. A recent pilot study tested one such
device on 18 healthy volunteers and concluded it had the potential to
provide the benefit of marijuana without the toxic smoke.

The psychoactive effects of marijuana make it difficult for users to
function in society while on a marijuana high. Those desiring to
operate a vehicle or machinery, conduct a conversation, get to work
on time, stay awake or learn new things may find it difficult to
conduct routine business while high on marijuana. These side effects
were found particularly hard for patients not already familiar with
marijuana use.

Other physiological effects from marijuana use such as increased
heart rate and its effects on blood pressure make it a concern for
older patients already suffering from heart disease, potentially
leading to heart attacks or other cardiovascular event.

Medical Treatments

A review of the literature shows that very few rigorous studies have
been conducted on the use of marijuana to treat disease. While
cannabinoid receptor locations in the brain offer some insight into
which diseases may be helped by drugs developed from marijuana, most
studies have involved few participants and were not conducted
following traditionally recognized methods for evaluating treatments.
Despite this, some synthetic derivatives from marijuana are now
available and are being prescribed to patients for specific ailments.

A large part of the medical research community has recommended
increased research into how marijuana compounds can be harnessed to
reduce suffering while minimizing any negative effects.

Despite recognizing the substantial potential for future benefit, the
IOM study believed that only a small group of patients would actually
benefit from using marijuana. The study observed that for most
symptoms marijuana was being considered to treat there were other
more effective treatment options, which most patients responded to.

For cancer patients undergoing chemotherapy, the study found the
public was not aware of the major strides made in medicine to treat
nausea and side effects. While cannabinoid substances were only
effective in 24 percent of the cases, a combination of currently
available drugs is considered nearly 100 percent effective if started
before chemotherapy begins. Because pills are less effective once a
patient starts vomiting, an inhaled fast acting drug, such as the THC
from marijuana could provide some benefit.

For HIV patients, while marijuana may provide some relief from
wasting diseases it has also been linked to suppressing the immune
system. For unknown reasons the relative 12-year risk of death from
marijuana smokers with HIV is nearly twice that of those not using
it. Many HIV patients are effectively taking synthetic derivatives
of marijuana for wasting diseases.

In a 2003, 23 percent of HIV patients in a public health study in San
Mateo used marijuana. Of those users, only 17 percent met the strict
definition of medical marijuana use for the relief of nausea,
anorexia or pain. Some used a synthetic to treat AIDS wasting and
smoked marijuana recreationally.

Marijuana is no longer believed by most to be an effective treatment
for glaucoma. While it does temporarily reduce the pressure within
the eye, it acts for a short period of time and reduces the blood
flow to the optic nerve, potentially damaging it. Other treatments
are now considered significantly more effective in managing glaucoma.

For multiple sclerosis, the studies have not shown marijuana to be
particularly effective in managing the pain, spasticity or the
disease. Studies have had mixed results, although the cannabinoid
receptors are particularly abundant in areas of the brain controlling
movement so further study is being conducted.

2007 Research Developments

Some new studies show the importance of being able to deliver
predictable and repeatable dosages of THC to patients and clearly
established that more is not always better.

A study of 15 healthy volunteers found that medium doses of marijuana
relieved some neuropathic pain in healthy volunteers while higher
doses actually made the pain worse. Neuropathic pain is associated
with cancer, AIDS, diabetes, etc. Low doses had no effect. Report
published in October 2007

While low doses of THC seem to alleviate depression, higher doses
makes the depression worse, concluded McGill University researchers
in a report published in October 2007.

These studies show the value of being able to control and adjust the
amount of THC delivered to a patient to get the desirable outcome.

Other Developments

Foot pain associated with HIV (neuropathic) shows some relief from
smoking marijuana over a placebo according to a study in February 2007.

Smoking one joint causes the same lung damage as three to five
tobacco cigarettes according to an August 2007 Danish study.

A cannabinoid called CDB in marijuana has shown early promise in
laboratory tests for treating metastatic forms of breast cancer. Very
small quantities of CDB are present naturally in marijuana. Published
in November 2007.

THC may help the virus causing Kaposi's sarcoma both infect healthy
cells and then multiply according to a study conducted by Harvard
Medical School researchers and published in August 2007. Kaposi's
sarcoma is a cancer affecting those with depressed immune systems
such as HIV and transplant patients.

A team of Swedish researchers has identified how the brains of unborn
babies are damaged by mothers smoking marijuana, published in May 2007.

Harvard researchers have shown in lab and mice studies that certain
THC treated lung cancer cells grew at half the rate of untreated
cells, published in April 2007.

Research done in Cardiff University in Wales, suggests that marijuana
use could increase the risk of developing psychotic illness later in
life by 40 percent, published in August 2007.

THC may help reduce the symptoms of allergic skin disease according
to study on mice by an international group of researchers published
in August 2007.

GW Pharmaceuticals in Britain has been conducting tests for eight
years on Sativex, a prescription drug derived from cannabis to
relieve symptoms of neuropathic dysfunction and pain. The drug is
being reviewed in Canada for market approval.

[sidebar]

EDITOR'S NOTE - Information on the medical effects of marijuana was
gleaned from research published in a variety of scientific journals.
The basis of much of the article came from the Institute of Medicine
Marijuana and Medicine study published in 1999, which was requested
by White House Office of National Drug Control Policy in 1997. While
the study is much referenced by medical marijuana support groups, it
is less quoted in White House drug policy. The IOM is one of four US
National Academies and is a not-for-profit and non-governmental
agency established as an independent think tank to advise the nation
on matters concerning health and medicine. It remains the most
comprehensive treatise available on the issue. The Canadian Senate
authored a similar study in 2002 that mirrored much of the IOM
findings. Many of these findings were also supported by several
sponsored reports from the UC Center for Medical Cannabis Research
and the Medical Board of California marijuana policy. An effort was
made to focus this article on the science associated with marijuana's
medical value and not explore other medical marijuana issues.