More Evidence That Marijuana-Like Drugs May Help Prevent PTSD

Not sure if it will "prevent it" but I know a lot of veterans helped by it. It calms them down when nothing else seems to be able to.

More Evidence That Marijuana-Like Drugs May Help Prevent PTSD
By Maia Szalavitz Friday, September 23, 2011

Could a marijuana-based medicine potentially prevent the symptoms of post-traumatic stress disorder (PTSD)? If the findings of a new study in rodents hold up, they may offer a new avenue for treatment of an illness that affects at least 7% of Americans during their lifetimes.

For the study, published in the journal Neuropsychopharmacology, researchers exposed rats to severe, Navy Seal-level stress, including restraint, forced swims and anesthetization. Luckier control rats just stayed in their cages and were handled twice by researchers.

Like humans who develop PTSD, the stress-exposed rats later became oversensitized to more moderately stressful stimuli, showing an exaggerated startle response to loud noises, for example.

These rats also took longer to recognize that a once scary spot in a cage was now safe. Animals that had experienced traumatic stress also showed related changes in stress hormones.

But rats that were severely stressed, then immediately given a synthetic compound that mimics the effects of THC, the main psychoactive ingredient in marijuana, were mellower. They showed none of the stress-related changes seen in the rats receiving placebo.

The timing of the drug (known as WIN55, 212-2) mattered, though. The injections prevented symptoms of PTSD when they were given two or 24 hours after stress, but had no effect when administered 48 hours later.

The study, which involved a total of 637 male rats included in a series of 16 experiments, follows up similar previous work by the same author, this time using different tests of stress.
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