Twenty states and Washington, DC, have now legalized the use of medical cannabis.
With all the attention legalized medical marijuana has been receiving, it is curious that very little attention was given to this topic during the recent meeting of the American Psychiatric Association (APA) in San Francisco. It was particularly ironic because while the APA was holding its meeting, San Francisco was hosting the International Cannabis and Hemp Expo, which promoted the culture of cannabis use. All you needed to gain entry was $15 and a medical complaint . . . such as insomnia or back pain.
Given the omission of meaningful discussion during the APA meeting—and the apparent confusion on the part of many psychiatrists about prescribing the substance and the ethical issues that it poses for many—Psychiatric Times has conducted a survey on the topic. Psychiatrists were invited to complete the survey and give their candid feedback on the subject. Results of that poll are summarized here.
Many of our patients have started asking if they are candidates for a prescription. I am a geriatric psychiatrist, and I have seen a surge in the use of marijuana (whether medicinal or not) by aging adults who may have used it in their youth. It is frequently provided to the elderly by their middle-aged children for pain, insomnia, anxiety, weight loss, and—more recently—the agitation associated with dementia. Many report improvement in these symptoms and ask me to approve the use of medical marijuana throughout the day to help “mellow out” their parent. (The use of medical cannabis is legal in California where I practice.) This request puts me in the awkward situation of having to know about—and unwillingly consent to—marijuana use but not being able to prevent it.
Cannabis is commonly regarded as an innocuous drug. The prevalence of lifetime and regular use has increased continuously in most developed countries. However, accumulating evidence highlights the risks of dependence and other adverse effects, particularly among people with preexisting psychiatric disorders. We all know that the use of marijuana in the context of psychiatric illness can worsen symptoms (eg, it can increase anxiety and paranoia). Others report that marijuana diminishes their symptoms of anxiety, sleep, or pain. Longterm use of marijuana can also cause apathy and low motivation. An appreciable proportion of cannabis users report shortlived adverse effects, including psychotic states following heavy consumption, and regular users are at risk for dependence. People who have major mental illnesses, such as schizophrenia, are especially vulnerable in that cannabis gener ally provokes relapse and aggravates existing symptoms.
Cannabis is a risk factor for mental illness. It can cause or create:
• Psychological responses such as panic, anxiety, depression, and psychosis. These effects may be described as “toxic” in that they generally relate to excess consumption of the drug
• Effects on preexisting mental illness
• Dependency or withdrawal effects
At the same time, there is still no evidence for the use of medicinal marijuana for most disorders. Some evidence suggests that it helps in alleviating nausea (eg, in patients receiving chemotherapy), muscle spasticity in spinal cord injuries, and some neuropathic pain. Marijuana is still classified as a Schedule I drug (in the same category as LSD, PCP, and methamphetamines), while cocaine, for example, is classified as a Schedule II drug. This limits the ability of researchers to explore potential medical uses for marijuana.
Given the paucity of evidence for the uses of medicinal cannabis, and still very unclear and conflicting local and federal laws, physicians will be careful in prescribing medicinal marijuana.
Thank you for taking the survey— results of which can be viewed here. We invite you to view the results and add your comments.
[Editor's note: The New England Journal of Medicine recently polled physicians across specialties about their views on medicinal use of marijuana. The case vignette that was presented and the comments—pro and con—that it elicited can be viewed here.]
This article was first posted online on 6/7/2013 and has since been updated.