Stoned: A Doctor's Case for Medical Marijuana, by Dr. David Casarett (2015, Current Press, 289 pp., $27.95 HB)

[inline:casarett.jpg align=left]Medical marijuana is now legal in about half the US (even more if you include those states that have now passed limited CBD cannabis oil laws), but it still remains a controversial medical treatment. Many people still assume that it's a joke or, more nefariously, a charade designed to pave the way for the legalization of recreational marijuana.

Dr. David Casarett was one of them. He admits in the opening pages of Stoned: A Doctor's Case for Medical Marijuana that that he thought it was joke and that when he talked about medical marijuana as a treatment, he always mentally added quotation marks around "treatment." But in those same opening pages, he is introduced to "Caleb," a 40-something man from Michigan suffering from rectal cancer who has traveled to Colorado in search of medical marijuana and who swears by it.

"Caleb" has a shelf full of prescription medications, including heavy opiates, but he tells Casarett he doesn't want to use them because of the side effects and that marijuana works better at relieving his pain and making him tolerable to be around. The doctor has found himself a real life, bona fide medical marijuana patient.

But Casarett, a physician, researcher, and tenured faculty member at the University of Pennsylvania's Perelman School of Medicine, knows that anecdotal evidence isn't the same as good science. Ideally, "Caleb" would have been in a peer-reviewed double-blind clinical study along with hundreds of thousands of other patients. Casarett wants the science to be there, but it isn't yet, and he examines the reasons for that.

One of them is political. For years, the DEA has been an obstacle to research on marijuana's medical applications, all the while claiming that marijuana has "no accepted medical use." And with the DEA blocking the doorway, that means funding and implementing medical marijuana studies is more difficult.

But another reason is the nature of marijuana itself. It's a plant, not a synthesized chemical, and it contains hundreds of cannabinoid compounds. Western medical science will want to tease out and test each of those compounds in isolation, but it also needs to deal with the synergistic effects of the cannabinoids on each other. And then there are terpenes, the organic compounds that create essential oils, and are linked to psychoactive and medicinal effects as well. Western science doesn't want to deal with whole plants, but if it's going to address medical marijuana, it's going to have to.

As Casarett undertakes his year-long search for the truth about the plant and its medical applications, he takes the reader on a sometimes surprising, sometimes outright amusing tour of medical marijuana. We meet a young couple who turned to it to treat their two-year-old daughter's seizures, a young man who used it to deal with PTSD after a violent assault, an Israeli nursing home volunteer using it to treat anxiety and confusion in patients with dementia.

We also meet leading scientists and researchers in the field, such as Dr. Donald Abrams, the San Francisco-based oncologist, who warns Casarett of quackery surrounding claims that marijuana can cure cancer. While there are some promising research results, the science just isn't there yet, and when hope and hucksterism collide, the results can be not only sad, but tragic.

Casarett comes away convinced that marijuana does indeed have proven medical uses -- he cites neuropathic pain and nausea -- as well as conditions that may well be helped by it, such as insomnia, PTSD, or the symptoms of dementia or Parkinson's, but that it also has dangers. Casarett worries about marijuana's addictive potential, which he calls "substantial," and he think marijuana impairs drivers as much as alcohol does. He also notes the danger of psychotic episodes or, possibly, schizophrenia, as a result of marijuana use.

Even-handed observer that he is, he notes that the danger of pot addiction or the miniscule chance of developing psychosis is "trivial" with patients with serious, life-threatening and/or terminal medical conditions, but he also notes that many patients are young people not suffering from life-threatening conditions, and the long-term dangers are worth watching.

One of Casarett's most interesting contributions is to call for marijuana to be treated not like a medicine, but like an herbal remedy: "It's essentially plant-based stuff with numerous active and inactive ingredients, only some of which we understand," he writes. That's not a fatal flaw, he argues, pointing to the widespread use of herbal remedies like black cohosh, Echinacea, Gingko Biloba, and St. John's Wart.

He also calls for marijuana's cannabinoids to be placed in Schedule II of the Controlled Substances Act. This approach seems eminently sensible. Leave the raw plant alone, schedule the chemical compounds. That way, marijuana can be medicalized without leaving non-medicinal consumers looking for a prescription to get high. With Stoned, Dr. Casarett has embarked on a knowledge-seeking journey, and he has found much to mull over. Readers who are game enough to join him are going to learn some things and have a good time along the way. Highly recommended.