Is medical marijuana effectiveness more hype than actual benefit?

Dr. Keith Roach

Question: What advice do you have for both doctors and patients for approaching medical marijuana use? What is your ideal vision of its future? — C.C.

Answer: I look at marijuana as a potentially useful medicinal plant that has several potential downsides. One of the downsides is an unrealistic expectation of its usefulness by believers. I increasingly see claims that marijuana (or one of its extracts) can treat or cure almost every known disease. It also is hampered by its status as a Schedule I drug by the Drug Enforcement Agency, so high-quality research is difficult to do. Finally, it has been used for many years as a recreational drug (which is partially responsible for the first two downsides). This has led to resistance to the idea among nonbelievers that it might have legitimate use. The psychological effects for which it is used recreationally can cause it to be intolerable for some. Further, a small percentage of people have difficulty quitting the drug, even when they want to.

Marijuana contains many potentially active chemicals, of which only two (THC and cannabidiol) have been studied well. The best evidence of effectiveness for any type of marijuana product is in epilepsy and chronic pain, but the quality of the data is limited. There are very few situations where I would consider prescribing medical mari- juana, but they do exist.

Most of the risks of medical marijuana are also unknown. Anecdotal reports suggest that fewer users of medical marijuana are smoking it, in favor of ingesting extracts. I suspect that this will lead to lower risk of heart and lung problems, but I withhold judgment until there are good data. It also is clear that marijuana can cause or worsen anxiety in some people. Adolescents who use marijuana may be at higher risk of schizophrenia.

My ideal future regarding medical marijuana is one where it is studied openly and subjected to the same scrutiny as other medicines, where both the purified extracts are studied as well as the whole plant.