pros and cons of cannabis

On Jan. 11, two doctors, speaking before the Health Quality Subcommittee of the Florida House of Representatives, gave very different accounts of whether cannabis is harmful or beneficial.

The 15-member subcommittee, meeting on Jan. 11 at the state Capitol in Tallahassee, heard Dr. Bertha Madras and Dr. Sue Sisley discuss the cons (Madras) and pros (Sisley) of cannabis.

Pros and Cons of Cannabis

Dr. Bertha Madras

Madras, who spoke first, focused much of her discussion on recreational, not medical, cannabis. She is a professor of psychobiology in the Department of Psychiatry at Harvard Medical School. Much of her research focuses on addiction biology.

Dr. Bertha Madras / pros and cons of cannabis

Dr. Bertha Madras

Her strongest opposition was to recreational-marijuana use, especially by adolescents. Among users, “The most robust changes are in the adolescent brain.”

Adult users, too, are also harmed, she explained: “30.6 percent of those who currently use cannabis have a spectrum of cannabis-use disorder.” That disorder is defined by as “the continued use of cannabis despite clinically significant distress or impairment”; i.e., abuse.

Tone remained civil

During their respective presentations, both physicians spoke at all times in calm, measured tones and periodically answered questions that members of the House subcommittee posed.

Other harmful effects among longtime users, especially those who started using marijuana as adolescents, is a drop in IQ and a loss of memory capacity. The declines are “dose-dependent,” she noted.

The higher the strength of the marijuana, and the longer the period of use, the more likely a user is to develop such problems. How harmful can the effects be? “The strength and frequency of marijuana use increases the risk of psychosis,” she said.

Madras also quoted an Australian study that says more marijuana users are on welfare or unemployed than those who don’t use.

She seemed to criticize at least some of the people advocating for cannabis: “The drivers of this movement … have unfulfilled medical needs, psychiatric problems, social problems.”

Madras also warned that “Right now, there is very little science behind cannabis” and that not enough safeguards are being used to protect consumers using it.

Dr. Sue Sisley

Sisley is a longtime supporter of safe, legal access to cannabis who has studied the subject for a decade. As part of her research, the Scottsdale, Arizona, physician works with veterans who use cannabis in their treatment. She started off by saying that she has never used cannabis and has no financial stake in the industry.

Dr Sue Sisley / Pros and cons of cannabis

Dr. Sue Sisley

She discussed a study in which a doctor documented a 75 percent decrease in the severity of PTSD (post-traumatic stress disorder) in military veterans using medical cannabis. Sisely, who has been treating military veterans for 20 years, said, “It’s very rare that I can ever achieve 75 percent decrease in these patients with traditional, standard medication.”

Sisley said that the greatest documented effectiveness of medical cannabis is in treating multiple sclerosis.

Cannabis might help to fight cancer

But she also noted that the medication might prove useful in fighting cancer, and that some phase-1 trials are now being conducted on its anti-cancer properties.

She discussed a case report that has been submitted to The Journal of Dermatology for publication. “The patient had a squamous-cell cancer, and her first line of treatment was a daily application of a high-THC formulation” of cannabis. “She applied it to the lesion every day for a full month. We did a repeat biopsy that was negative.”

A variety of trials should be conducted to determine cannabis’s effectiveness on health issues such as pain, cancer and other maladies, she said.

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