Some psychiatrists and other physicians who treat pain have been open for some time to recommending medical cannabis for their patients. The psychiatric community in general, however – largely because of concerns about addiction and psychosis – has been reluctant to do so, despite the drug’s proven benefits for illnesses such as anxiety, posttraumatic stress disorder, and mood disorders.

But this reluctance might be changing, some psychiatrists say.

“Clinicians are increasingly open to this kind of dialogue,” said Christopher G. Fichtner, MD, a Fellow of the American Psychiatric Association (FAPA), and clinical professor of psychiatry at the University of California, Riverside. “As a doctor, I try to be aware of how my patients are using cannabis, what benefits they may attribute to it, and whether they have problems related to its use. At times, it may be possible to advise them about the value, for example, of products rich in cannabidiol (CBD) – known to be anxiolytic, possibly antipsychotic, and potentially mood stabilizing – as opposed to products higher in tetrahydrocannabinol (THC) that are more psychoactive and may aggravate psychotic symptoms for some patients.

“Our ability to advise patients along these lines is helpful to the extent that patients are able to consistently obtain reliable cannabis products,” Dr. Fichtner said, noting that European and Brazilian research supports the view that CBD might have some antipsychotic properties ( Schizophr Res. March 2015;162[1-3]:153-61 ) and ( Schizophr Res. 2015 May;164:[1-3]:155-63 ).

Currently, 25 states and the District of Columbia have legalized cannabis for medical use; and voters in three additional states – Arkansas, Florida, and North Dakota – approved medical cannabis measures on Nov. 8. “Although medical marijuana laws have not made it possible to prescribe cannabis in the strict sense, they allow doctors to recommend it for patients who experience benefit from using it,” Dr. Fichtner said. “Cannabinoid products available in dispensaries are not subject to the same level of regulation and quality control as Food and Drug Administration–approved medicines, but they are often labeled qualitatively and/or quantitatively with the result that they probably are more reliable than marijuana obtained on the streets.”

Traditional vs. counter views

The American Psychiatric Association came out strongly against cannabis use for medicinal purposes in 2013. The APA’s position statement cites the absence of “current scientific evidence” showing that marijuana is in any way beneficial for treating “any psychiatric disorder. In contrast, current evidence supports, at minimum, a strong association of cannabis use with the onset of psychiatric disorders,” the statement says. Likewise, the American Medical Association reaffirmed its opposition to the use of medical cannabis in 2013, citing the drug as a “public health concern.” Another medical group that is in strong opposition to the use of medical cannabis is the American Society of Addiction Medicine (ASAM). In addition to rejecting smoking as a means of delivery, ASAM’s policy statement says “cannabis, cannabis-based products, and cannabis delivery devices should be subject to the same standards that are applicable to other prescription medications and medical devices.”

In a policy revised in 2015, the National Institute on Drug Abuse (NIDA) said that although the FDA has neither recognized nor approved the marijuana plant as medicine, the FDA has approved three medications that contain cannabinoid chemicals. Marinol and Syndros, which include dronabinol, a synthetic delta-9-THC, are approved for treating anorexia tied to weight loss in patients with AIDS. Cesamet, which contains nabilone and has a chemical structure that is similar to THC, also has received FDA approval for nausea and vomiting caused by cancer chemotherapy.

Earlier this year, a new organization founded by David L. Nathan, MD, a Distinguished Fellow of the APA (DFAPA), joined the cannabis debate. The group, known as Doctors for Cannabis Regulation ( DFCR ), does not advocate for the use of medical cannabis. However, DFCR does support, among other things, “cannabis legalization for adults, preventive education of minors, and regulation of the industry.”

“A social justice aspect overlays the whole discussion,” said Steve Daviss, MD, DFAPA, a DFCR founding member and president of FUSE Strategies for Behavioral Health Integration in Baltimore.

DFCR argues that prohibiting cannabis overburdens the criminal justice system, drains law enforcement, and treats African Americans unfairly, saying that population is “nearly four times more likely than whites to be arrested for cannabis possession, despite similar usage rates between the two groups.” The group, which launched with more than 40 founding members – including 10 psychiatrists – also cites evidence showing that medical cannabis use is correlated with a 25% reduction in deaths from opioid use. In 2014, Marcus A. Bachhuber, MD, of the Philadelphia VA Center, and his colleagues reached those conclusions after comparing three states with medical cannabis laws that were effective before 1999 with 10 states that had enacted medical cannabis laws between 1999 and 2010 ( JAMA Intern Med. 2014;174[10]:166-73 ).

“This is a rapidly changing area; new therapeutics are being developed; and there is great potential for good here” as well as the potential for risks, just as with any other medicine,” said Dan Morhaim, MD, an emergency medicine physician who represents Baltimore County’s 11th legislative district in the Maryland House of Delegates. “It’s not the devil weed; nor is it a panacea,” said Dr. Morhaim, who was active in the process of passing Maryland’s medical cannabis law. “Our job ought to be to see it as another tool in the toolbox to be used responsibly, just as we would with any other medicine.”

Weighing U.S. data

Most of the data on cannabis come from studies of recreational use, Dr. Daviss said. “We know that it can contribute to symptoms of depression, anxiety, psychosis, and addiction. Younger users are particularly at risk for some of these symptoms. We don’t really know how much of this risk applies to monitored medical use,” he said. “And some states have no requirements for monitoring and modulating the dose, so risk data from these states will be different from states where medical use is more regulated and more similar to standard medical care.”

In addition, data on the benefits of marijuana for psychiatric conditions are limited, Dr. Daviss said. “I have certainly heard directly from patients about how marijuana helps them,” he said. “These comments often suggest improvements in sleep, appetite, mood, and anxiety. “A major concern of psychiatric clinicians is that many people asking for medical cannabis are providing contrived reports of symptoms in an attempt to obtain marijuana for nonmedical (recreational) use,” or to share or sell, he said.

Clinicians also remain concerned that “one’s state medical license or federal [Drug Enforcement Administration] license could be at risk for ‘prescribing’ or ‘recommending’ medical cannabis,” Dr. Daviss said. “Being known as a ‘pot doc’ is not viewed as a career booster and could be seen as a risk factor for enhanced regulatory scrutiny of one’s practice.”

However, “there are many who balance those concerns with a harm reduction approach that acknowledges that drug cartels and gangs are fueled by marijuana sales, resulting in preventable violence and deaths, marijuana of unknown quality or adulteration, and negative criminal justice consequences for what should be viewed as a public health problem rather than a criminal problem,” Dr. Daviss said. “Such a harm reduction perspective may increase the likelihood that some physicians will support the use of either medical cannabis or recreational marijuana.”

As more researchers study medical marijuana, the concerns of psychiatrists will evolve along with the science, Dr. Daviss predicted. Relevant outcomes research would include comparative effectiveness studies such as a randomized, double-blind trials of standardized cannabis formulations versus standard treatment for depression or anxiety, he said.

There’s not enough evidence for specific contraindications for medical marijuana use in psychiatry, Dr. Daviss said. However, most clinicians would say that a psychotic disorder such as schizophrenia is a contraindication, because some users of medical marijuana experience paranoia and other psychotic symptoms, he noted.

Dr. Fichtner agreed, and said “studies do find an association between adolescent marijuana use and later development of psychotic disorders, including schizophrenia.

“Even though authors of such studies extrapolate their findings to public health implications in terms of reducing the number of cases of schizophrenia through prevention of marijuana use, such a cause and effect relationship is far from clear – and such conclusions are unwarranted,” he said.

In fact, he said, at least one small case series found prescription molecular THC to be a helpful adjunct to approved antipsychotic medications in schizophrenia patients who reported symptomatic benefit from previous marijuana use ( J Clin Psychopharmacol. 2009 Jun;29[3]:255-8 ). “Even more compelling,” Dr. Fichtner said, “are data on antipsychotic effects of molecular CBD, an important component of herbal cannabis that does not have THC-like psychoactive effects but has been demonstrated to have anxiolytic properties in a number of human studies.”

Dr. Fichtner said authors of research articles on the association between schizophrenia and cannabis use rarely have grappled with the possibility that patients might experience therapeutic benefits through self-medication. In addition, he said, “there are findings in the literature suggesting that among patients with schizophrenia, those using marijuana may have fewer and more selective cognitive deficits than those who do not use marijuana.”

For his part, Dr. Morhaim also supports an open approach. “All health professionals, psychiatrists included, need to consider cannabis as any other medicine,” Dr. Morhaim said. “It has its uses and side effects; reasons to initiate use and reasons to stop; diagnoses for which it is generally accepted that it works (multiple sclerosis, nausea from cancer chemotherapy, and appetite loss) and ones where [effects are] less clear. The medical-scientific potential, however, is expanding rapidly as the shackles that have blocked proper cannabis research are coming off,” he noted.  

Several large studies evaluating the use of cannabis for mental illness are underway, Dr. Morhaim said. As the science expands, recent studies have examined the role of cannabis for treating a range of medical conditions, including Alzheimer’s disease, multiple sclerosis, migraine, and even fracture healing and acne, he said. Still, data remain sparse. For example, a literature review that looked at randomized, clinical trials and meta-analyses tied to marijuana and other cannabinoids, and specific diagnoses found no trials that examined marijuana’s efficacy for treating Tourette disorder, PTSD, or Alzheimer’s disease ( J Clin Psychiatry. 2016 Aug;77[8]:1050-64 ). “Given its rapidly changing legal status, there is an urgent need to conduct double-blind, randomized, placebo- and active-controlled studies on the efficacy and safety of marijuana or its constituent cannabinoids for psychiatric conditions,” wrote Samuel T. Wilkinson, MD, of the department of psychiatry at Yale University, New Haven, Conn., and his associates. Meanwhile, a matched case-control, cross-sectional evaluation of veterans with probable PTSD found no significant differences between cases and controls in PTSD scores and frequency of cannabis use ( J Affect Disord. 2016 Jan 15;190:439-42 ).

Nevertheless, “psychiatrists ought to be familiar with medical cannabis, because they may be taking care of patients who are on it for other (somatic) reasons,” Dr. Morhaim said. “This is just like my work as an emergency doctor; I don’t prescribe psych medicines, but I have to know about them, because patients come to the ER who are on them.”

Lessons from patients’ reports

Rachna J. Patel, DO, a psychiatrist who describes herself on her website as “The Medical Marijuana Expert,” treats patients with anxiety and PTSD, and agrees that marijuana is a tool that, when used correctly, can benefit patients. “A visit with me, a medical marijuana doctor, is much like a visit with any other doctor,” said Dr. Patel, who practices in Walnut Creek, Calif.

“I have my patients complete a form that asks about their medical history, as well as the treatments they’ve sought out for their anxiety and/or PTSD, such as prescription medications, therapy, and other methods,” she said. “I then sit down with the patient to go over their history and do a focused physical exam. Once I determine that the patient’s medical condition will benefit with the use of medical marijuana, I spend the remainder of the time step-by-step walking him or her through how to use medical marijuana for the anxiety and/or PTSD,” she added.

Dr. Patel applies some basic considerations when assessing patients for potential medical marijuana treatment, notably the efficacy and side effects of past treatments and patient concerns about past treatments, including the potential for dependency or addiction. She also assesses the impact of anxiety or PTSD on the patient’s quality of life.

Education is key, she said, to addressing patients’ concerns and managing possible risks. “The risks are generally minimized and even eliminated by educating patients on selection of the appropriate combination of cannabinoids, as well as teaching them to use medical marijuana at the lowest effective dose and with the lowest effective frequency,” she said.  

“Having practiced in the field of medical marijuana for 4-plus years, I haven’t found marijuana to be a gateway drug,” she said. “The patients I see aren’t looking to ‘get high’ off of medical marijuana. In fact, they’re seeking to get off of the pharmaceutical drugs they’ve been prescribed.”

Dr. Patel walks patients through what she calls “The Patel Protocol for Medical Marijuana,” which includes “teaching patients how to select the appropriate combination of cannabinoids in marijuana products, figuring out how much to use and how often to use it, how to avoid side effects, and what to do in case patients do experience side effects,” she said.

In her experience, “when it comes to dosing, just like with many pharmaceutical medications, it really varies from patient to patient, even more so because cannabinoids are hydrophobic, so their pharmacology is not typical of most pharmaceutical medications.” Dr. Patel follows up with her patients often by phone after the initial office visit, then continues with office visits at least once a year.

“The best way any doctor can help to monitor their patients’ use of medical marijuana is to be as informed about it as any other pharmaceutical drug they’re prescribing,” she said. “Become familiar with the pharmacology [of medical marijuana],” she advised. “Know what scenarios could lead to side effects and how those side effects can be avoided. Know in what scenarios it [marijuana] can exacerbate underlying medical conditions.”

Dr. Fichtner agrees with Dr. Patel’s approach but adds that he generally does not recommend cannabis as a first-line treatment for his patients with serious mental illness. Rather, his approach generally is to prescribe evidence-based treatments.

“But when I do find a history of marijuana use and the patient reports it has been helpful, I work with the patient to assess possible benefits in the areas of symptom management and possible reductions in polypharmacy,” he said. “The latter is of particular concern in PTSD, where patients may be on complex multidrug regimens involving off-label medication prescriptions with only partial symptom relief. It is important to take the patient’s claim seriously, rather than merely jumping to the conclusion that they have a substance use disorder that is undermining their psychiatric care.”

Dr. Patel said a surprising and positive side effect she has observed during her years of recommending medical marijuana is that patients’ use of any anxiety and PTSD medication decreases over time.

“Even though I never expected it, with the use of medical marijuana, many of my patients have been able to significantly reduce or even eliminate the use of their prescription medications for their anxiety and/or PTSD,” she said. “Over time, I find that patients use the medical marijuana on an as-needed basis.”

Dr. Fichtner is the author of book, “ Cannabinomics: The Marijuana Policy Tipping Point ” (Northbrook, Ill.: Well Mind Books, 2010). Dr. Daviss, Dr. Morhaim, and Dr. Patel had no relevant financial conflicts to disclose.