Marijuana as a Treatment for PTSD?

The U.S. Department of Veterans Affairs has received wave of criticism over the department’s prohibition on providing prescriptions for medical marijuana to patients, even for patients living in the 14 states that have legalized medical marijuana. State and federal political differences appear to be playing a role in the decision, as the Drug Enforcement Agency lists marijuana on the Schedule I classification, reserved for substances not accepted for medical use. Many find this decision disappointing, given the large number of veterans returning from war with posttraumatic stress disorder (PTSD), with estimates of approximately 20 percent of recent war veterans meeting PTSD diagnostic criteria (Rand Corporation, 2008). While no reported randomized clinical studies have examined the effect of cannabis for the treatment of PTSD, the cannabis users report increased feelings of relaxation and decreased anxiety (Gonzalez, 2007; Woolridge et al., 2005). Anecdotal evidence suggests potential promise of cannabis for treating anxiety disorders. In addition, a recent report found that PTSD symptoms were positively associated with increased coping-oriented motives for marijuana use, such that those with higher PTSD symptoms reported using the substance to relieve negative emotional distress (Bonn-Miller, Vujanovic, Feldner, Bernstein, & Zvolensky, 2007).
The benefits of marijuana use will need to be weighed carefully against potential side effects. Cannabis-addiction has been the source of much work on substance use disorders, and presents an added complication in the use of medical marijuana (Cohen, 2009), especially given that individuals with PTSD have higher rates of substance use disorders than the typical population (Bremner, Southwick, Darnell, & Charney, 1996). Providing substances with high addiction potential in order to treat a disorder in which psychosocial treatments have shown tremendous efficacy is ethically questionable. Other notable side effects of marijuana use include risk for lung cancer (Ben Amar, 2006), decreased attentional abilities (Barnett, Licko, & Thompson, 1985), and positive psychotic symptoms (Morrison et al., 2009).