SAN JOSE, California—Michael Bledsoe's story begins like that of many other Iraqi war veterans. In 2007, he was chasing insurgents through Anbar province when a roadside bomb exploded, breaking Bledsoe's back and both his feet. A former Army Ranger working as a security contractor, Bledsoe soon knew his high-paying military career was over.

Back home, Bledsoe (not his real name) felt angry almost constantly. Nightmares haunted him. He withdrew and became isolated. "It was a serious sense of loss," he says. His psychiatrist quickly diagnosed post-traumatic stress disorder (PTSD).

Despite months of talk therapy, the nightmares continued, and Bledsoe grew desperate. Then "something almost miraculous" happened, he says. An online search brought him to a unique study of the banned drug MDMA (3,4-methylenedioxymethamphetamine), well known as the street drug ecstasy. The 21-patient study, sponsored by the nonprofit Multidisciplinary Association for Psychedelic Studies (MAPS), launched in 2004 as the first U.S. clinical trial of a psychedelic drug in 35 years.

After several bond-building sessions with psychiatrist and study leader Michael Mithoefer and a co-therapist, Bledsoe swallowed a white tablet, donned eyeshades and reclined in Mithoefer's comfortable Charleston, S.C., office. Over the next eight hours, Bledsoe revisited the explosion and recounted the trauma to Mithoefer. After two more MDMA-assisted psychotherapy sessions, Bledsoe says his PTSD symptoms were "completely eliminated."

This weekend at a MAPS-sponsored meeting here, Mithoefer reported similar results for nearly all of the trial's participants. After two or three MDMA sessions, patients who received MDMA experienced huge drops in symptoms as measured by a standard PTSD scale. At baseline, study patients had an average Clinician-Administered PTSD Scale (CAPS) score of 79, but after MDMA-assisted therapy, CAPS scores dropped to 23.4 in the 13-person MDMA group, whereas an eight-person placebo group averaged a score of 60. (Later, seven of eight placebo patients chose to receive MDMA as well.)

The improvements appeared to endure, Mithoefer reported. After an average of 3.5 years, 13 of 16 patients remaining in contact with the researchers no longer met the criteria for PTSD.  However, two of the patients "clearly relapsed," Mithoefer says. In addition, many of the patients returned to using antidepressants and other psychoactive medications, though the total number of prescriptions in the group was much lower than before.

Julie Holland, a psychiatrist in New York City who used to work at the James J. Peters VA Medical Center in the Bronx, says the data "look really great. It's amazing that when patients are done with therapy, they don't meet criteria for PTSD. I've never even seen that. It's a very big deal." If MDMA were legal, Holland added, she would "absolutely" use it in her practice.

Brain-imaging studies in healthy volunteers show that MDMA quiets the amygdala, an almond-shaped structure deep in the brain that some researchers call a “fear center” due to its central role in triggering strong negative emotions. MDMA also releases a flood of the brain messengers serotonin and dopamine while increasing blood levels of the hormones oxytocin and prolactin, which promote social bonding. This potent mix diminishes fear and defensiveness and boosts empathy and the desire to connect with others, says Holland, so “the therapy work goes faster and deeper.”

Veterans suffer very high rates of PTSD, according to surveys. One 2004 study in The New England Journal of Medicine estimated that up to 18 percent of Iraqi and Afghanistan combat veterans experience the disorder. "This is our way of trying to contribute to our moral obligations to our veterans," says MAPS founder and executive director Rick Doblin. He added that the U.S. Department of Veterans Affairs has rejected overtures from MAPS to work together on five separate occasions.

The U.S. Food and Drug Administration (FDA) has been friendlier to the group. This month, the agency granted MAPS permission to continue testing MDMA in 16 additional veterans with PTSD. But the road to full FDA approval is long and expensive, and Doblin anticipates five to 10 years of additional trials. He envisions eventually building a network of psychedelic therapy centers.

A dedicated network of therapists experimented with MDMA-assisted psychotherapy in the 1970s and 1980s before the U.S. Drug Enforcement Administration banned the drug in 1985. The next year, Doblin launched MAPS to revive psychedelic research, a movement that's now gaining steam. A dozen human studies of MDMA, LSD, a powerful African drug called ibogaine and psilocybin, from so-called "magic mushrooms," are now under way, testing the once-stigmatized drugs as treatments for not only PTSD, but also cluster headaches and addiction, as well as anxiety and depression in cancer patients.

Charles Grob, a psychiatrist at Harbor-UCLA Medical Center, dosed 12 end-stage cancer patients with psilocybin to test whether the experience could ease anxiety and help the patients cope with their diagnosis. Grob did not present his data, which are under review for publication, at the San Jose meeting, but the buzz on the results is positive. Grob and his co-investigators did offer snippets of letters and reactions from study patients. One said, “It feels like healing.” Similar studies of psilocybin in the terminally ill are now launching at New York University in New York City and Johns Hopkins University in Baltimore.

However, the going has been slow, with Doblin carefully dotting every regulatory "i" to prevent a second backlash against psychedelics. "This isn't the '60s," he says. "We've learned the lessons of that era, and now we're trying to integrate ourselves into science, into medicine, into society."

At the San Jose meeting, dubbed "Psychedelic Science in the 21st Century," that integration was in full swing. Eleven hundred therapists, physicians, basic researchers and psychedelics enthusiasts gathered for three days of scientific and cultural talks, visionary art shows and late-night celebrations. The unlikely mix found conservatively dressed researchers from prestigious universities mingling with the heavily tattooed and the green haired.

As for Bledsoe, he's now a true believer. His MDMA sessions were "an almost sacred experience, a very special and uplifting experience," he says. After the therapy, he vacationed in Jamaica, began dating a local woman and bought a house on the island. "I'm happy and well adjusted now," he says. "It's a good fairy-tale ending. As soon as we get some little Bob Marley kids it'll be even better."