The Senate passed a veterans' funding bill Tuesday, and on its website the Drug Policy Alliance activist group notes a historic rule change included in the measure: an amendment that would allow doctors working for the Department of Veterans Affairs to recommend medical marijuana use in states where the practice is legal.* The amendment was approved in May by the Appropriations Committee on a bipartisan basis; it's not included in the House's version of the spending bill and thus will now be subject to negotiation between the two chambers before being potentially sent to the White House.
The amendment was sponsored by Republican Sen. Steve Daines of Montana and Democratic Sen. Jeff Merkley of Oregon. Both of those states are among the 23 that have legalized medical marijuana use.
What use might veterans have for medical marijuana? Relieving chronic pain would seem to be one obvious possibility, and a review of research published in June 2015 by the Journal of the American Medical Association concluded that "use of marijuana for chronic pain ... is supported by high-quality evidence." The literature on marijuana's effectiveness for treating post-traumatic stress disorder seems to be more mixed. The VA's own website currently cautions that "controlled studies have not been conducted to evaluate the safety or effectiveness of medical marijuana for PTSD" and cites research indicating that using marijuana to treat PTSD can "lead to" tolerance and addiction. On the other hand, a study of 80 New Mexico PTSD patients in the Journal of Psychoactive Drugs found that "cannabis is associated with reductions in PTSD symptoms in some patients"—though that study did not involve a placebo control.
*Correction, Nov. 10, 2015: This post originally misidentified the Department of Veterans Affairs as the Veterans Administration.