Cannabis effects on PTSD: Can smoking medical marijuana reduce symptoms?

In 2009, New Mexico became the first state to authorize the use of medical cannabis for people with PTSD. Soon after the New Mexico PTSD regulation went into effect, one of the authors began receiving unsolicited phone calls from people asking to be evaluated as part of their application to the New Mexico Medical Cannabis Program. Therefore, the purpose of the study was to analyze data on PTSD symptoms collected during 80 psychiatric evaluations of patients applying.

The research, which took place from 2009 through 2011, involved patients who were pre-screened via telephone interviews. To be eligible for the study, participants must have met the following: the experience of and emotional response to a trauma that met the DSM-IV Criterion A for PTSD; the presence of several of the major symptoms in re-experiencing, avoidance, and hyperarousal of PTSD when not using cannabis; significant relief of several major PTSD symptoms when using cannabis; and lack of any harm or problems in functioning resulting from cannabis use. Participants were measured using a CAPS method approach. CAPS is an instrument in PTSD research that asks questions about the presence of traumatic experiences and the immediate emotional response to them, then establishes a rating of the frequency and intensity of symptoms on a scale of 0 to 4. Totals were then calculated.

The results indicated that patients in the sample reported an average of 75 percent reduction in all three areas of PTSD symptoms while using cannabis, yet further research is still called for by the researchers. "Many PTSD patients report symptom reduction with cannabis, and a clinical trial needs to be done to see what proportion and what kind of PTSD patients benefit, with either cannabis or the main active ingredients of cannabis," said Dr. George Greer, one of the researchers.