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UC San Diego Doctor Warns Of Medical Marijuana Risks

Photo caption: Customers buy products at a medical marijuana dispensary, April 20, 2016.

Photo credit: Associated Press

Customers buy products at a medical marijuana dispensary, April 20, 2016.

UC San Diego Doctor Warns Of Medical Marijuana Risks


Dr. Kai MacDonald, assistant clinical professor, UC San Diego


Former NFL players who want the league to allow use of marijuana to treat injuries will join doctors and companies selling new treatments in San Diego this weekend at the Southern California Cannabis Conference and Expo.

The conference will feature speakers advocating for wider use of medical marijuana to treat diseases from multiple sclerosis to menstrual cramps. But UC San Diego School of Medicine’s Dr. Kai MacDonald, who is not planning to attend the conference, stresses that very little is known about marijuana’s long-term side effects.

MacDonald, an assistant clinical professor of psychiatry at UCSD, recently wrote a paper for the journal Innovations in Clinical Neuroscience titled “Why Not Pot? A Review of the Brain-Based Risks of Cannabis.” MacDonald writes that marijuana is addictive, though far less so than nicotine or heroin, and use of marijuana by those with schizophrenia may lead to an increase in symptoms.

MacDonald is quick to note that he is not opposed to medical marijuana, but that due to federal restrictions on marijuana research and the increasing number of strains used to target specific diseases, there is not enough research into the drug’s long-term effects. Much of the current research into marijuana studied regular or heavy users, not those prescribed marijuana by a doctor, so some of the findings are not directly applicable, MacDonald said.

“In a person with any kind of terminal condition, it’s hard to wax poetic about long-term risks,” MacDonald said. “Look at the hospice population, with nausea and pain. That’s a really good place to ease suffering.”

MacDonald joins KPBS Midday Edition on Wednesday with more on the medical research into marijuana.

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