Marijuana's Benefits: Just Smoke and Mirrors?

A Legal Defeat Comes Amid Growing Evidence of Health Problems

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WASHINGTON, D.C., JUNE 11, 2005 (Zenit.org).- The controversial practice of using marijuana for medical purposes suffered a legal defeat Monday. In a 6-3 decision the U.S. Supreme Court upheld the federal government’s power to ban the drug’s possession in the states that allow its use.

The case arose out of a ruling on California’s Compassionate Use Act, approved by a referendum in 1996, known as Proposition 215, the Washington Post noted Tuesday. Another 10 states currently allow medical use of marijuana.

While the case was still pending, the New York Times last March 29 reported that marijuana’s benefits are far from being accepted by the medical profession. Although some individuals report having benefited from its use, Dr. Joseph Sirven, an epilepsy specialist and associate professor of neurology at the Mayo Clinic College of Medicine in Scottsdale, Arizona, said: «There’s a whole Internet literature suggesting what a wonderful thing it is. But the reality is, we don’t know.»

And the article quoted Dr. Donald Gross, director of the University of Alberta’s adult epilepsy program in Canada, as saying, «There’s not been a randomized, controlled trial demonstrating that marijuana or any cannabinoid is any more effective in controlled seizures than a placebo.»

Another expert, Dr. Kenneth Mackie, a professor of anesthesiology at the University of Washington, has devoted 15 years to studying the brain’s response to cannabinoids. He argued that there are no clinical studies proving marijuana’s positive effects in alleviating pain.

There are also substantial concerns over how the medical marijuana programs are operating, as the San Francisco Chronicle revealed in an in-depth study of the issue on April 24. The city now has 43 medical marijuana dispensaries. But few controls are in place to govern their operation.

According to the Chronicle, police in San Francisco say the quantity of marijuana in circulation has risen sharply. Police speculate that gang members and drug dealers buy marijuana at the dispensaries and sell it on the street.

Threat to mental health

Monday’s court ruling comes after the federal government launched a publicity campaign against marijuana use in May. The Chicago Tribune reported last Sunday that the government is taking out ads in newspapers and magazines across the nation, warning of the drug’s ill effects on mental health.

The ads cite studies that point to a link between regular use of marijuana and problems such as depression, suicidal impulses and schizophrenia. One of the reports, by the Substance Abuse and Mental Health Services Administration, interviewed almost 90,000 adults on their use of the drug.

Researchers found that adults who had used marijuana before age 12 were twice as likely to have experienced a serious mental illness in the past year as those who began smoking it after 18.

«The evidence is now pretty significant that central nervous system development is not complete in adolescents, and the use of this drug may have effects on the maturation of their central nervous systems,» said Dr. Richard Suchinsky, a psychiatrist who oversees the Department of Veterans Affairs’ addiction programs.

In England, a conference organized by the Institute of Psychiatry of King’s College in London late last year heard evidence that marijuana use roughly doubles the risk of psychiatric illness. According to a Dec. 2 article in London’s Telegraph newspaper, Jim van Os, a psychiatrist at Maastricht University in the Netherlands, said that a number of studies show that the drug roughly doubles the risk of psychiatric illness such as schizophrenia among young people.

A study carried out by the Dutch psychiatrist revealed even higher risks for those who are already genetically vulnerable to psychiatric problems. For those who had shown evidence of being predisposed to these conditions, marijuana use increased fourfold the risk of developing problems.

On Jan. 1 the Telegraph reported on comments made by Dr. Clare Gerada, head of the drugs misuse unit of the Royal College of General Practitioners. She said that relaxed attitudes toward marijuana use, combined with the greater availability of stronger varieties of the drug, were leading to rising rates of depression and psychosis among vulnerable young people.

The British press has published a number of reports on problems associated with marijuana use in the aftermath of the government’s decision, effective at the start of 2003, to downgrade the drug from Class B to Class C. The change means that those caught by the police using marijuana are let off with a warning. The drug is confiscated.

Altering the brain

Heavy use of marijuana has been linked to psychosis by a group of scientists in New Zealand. The National Post newspaper of Canada reported March 10 that the researchers followed a group of 1,200 men and women, all born in 1977, over a 25-year period. Their findings were published in the March edition of the journal Addiction.

«The association between cannabis use and psychotic symptoms is unlikely to be due to confounding factors,» wrote researchers David Fergusson and L. John Horwood. «The direction of causality is from cannabis use to psychotic symptoms.» The study showed that use of the drug probably alters the brain’s chemistry, thus precipitating mental health problems.

According to an April 12 article in the London-based Times newspaper, around a quarter of the population have a genetic vulnerability to psychotic illnesses if they use marijuana during their teen years. The problems did not arise just from marijuana use, or from the genetic problem by itself, but from a combination of the two.

The data came from a study led by Avshalom Caspi and Terrie Moffitt, of the Institute of Psychiatry at King’s College London, and published in the journal Biological Psychiatry. Caspi also noted that marijuana has many other adverse effects, for example, on respiratory health and possibly on cognitive function.

And a report in the Scotsman newspaper on May 23 raised the alarm that marijuana use may weaken the body’s bones. The finding came from researchers at Aberdeen University. Stuart Ralston, who led the study, said: «I wouldn’t want to strike fear into everyone who uses the drug, but our tests lead us to the conclusion that it might cause bone loss.»

Commenting on the results, Alistair Ramsay, the director of Scotland Against Drugs, said: «There is gathering evidence of a growing range of conditions caused by cannabis. Emphysema and early onset of lung cancer are now joined by possible osteoporosis and mental illness.»

In the Netherlands, meanwhile, efforts are under way to reduce the availability of marijuana through the country’s famous «coffee shops.» The number of these outlets where marijuana is freely available has declined from a peak of nearly 1,500 to about 750, and is continuing to shrink, according to a March 5 report in the British newspaper Independent.

According to the article, authorities are studying the effects of strong forms of cannabis, which could lead to a ban of these varieties. As well, the police are taking action against people who grow the drug at home.

In its annual report, published March 2, the International Narcotics Control Board welcomed the changes. In a press release accompanying its report, the agency noted that an official Dutch ministerial paper on marijuana admitted that the drug «is not harmless.» The government document stressed the importance of strengthening measures against street dealing, drug tourism and cannabis cultivation, as well as continuing to reduce the number of coffee shops. Marijuana’s popularity, at least at the government and medical levels, seems to be going up in smoke.

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