The state of Maine adopted a law on Tuesday permitting medical marijuana for the treatment of posttraumatic stress disorder (PTSD), while the New Hampshire Legislature approved similar legislation that is expected to be signed by the governor, according to a press release from The Marijuana Policy Project.

Oregon also last month joined California, Connecticut, Delaware, Massachusetts, and New Mexico in permitting health care providers to prescribe marijuana for PTSD, while legislation passed by the Illinois Legislature in May awaits the governor's pen.

The state-by-state legislative movement on this issue follows recent research supporting the drug compound's efficacy in treating the condition.

"There is mounting evidence demonstrating the benefits of medical marijuana for individuals suffering from PTSD," David Boyer, Maine political director for the Marijuana Policy Project, told reporters. "Maine lawmakers should be commended for taking action to ensure veterans and others living with PTSD are able to use medical marijuana to alleviate their symptoms and live healthy and productive lives. They deserve nothing less."

"A growing number of states are beginning to consider allowing the use of medical marijuana in the treatment of PTSD," Boyer said. "We hope they will move forward and follow the example that has been set by Maine and other states."

Boyd said that although the federal government has denied requests to conduct clinical trials of marijuana for PTSD, other research supports efficacy in relieving symptoms such as anxiety and traumatic memories, which characterize the condition. U.S. National Institute of Mental Health says 7.7 million American adults live with PTSD, including war veterans, accident victims, and survivors of abuse, among others.

Presently, 18 states and Washington, D.C. permit health care providers to prescribe marijuana to treat a variety of conditions, in addition to PTSD.

PTSD is a severe condition that may develop following exposure to one or more traumatizing events, such as combat, sexual assault, serious injury, or the threat of death. The symptoms include recurring flashback memories of the trauma and a high level of anxiety continuing for more than a month, often for years.