A US doctor believes combining MDMA, commonly known as ecstasy, with psychotherapy could cure patients who suffer severe post-traumatic stress disorder (PTSD).
Dr Michael Mithoefer used MDMA on 21 rape victims who had been living with PTSD for 19 years.
After being given permission from the government to use the drug in trials, Dr Mithoefer and his wife Ann, a nurse, administered two doses of MDMA during an intensive eight to 10 hour therapy session.
For the following week, the patients underwent 90-minute non-drug therapy sessions before repeating the treatment three to five weeks later.
Dr Mithoefer said the drug allowed the patients to focus on the sexual assault in a calmer and less fearful way, which helped them work through their problems.
After the treatment, the patients reported 75 percent lower levels of anxiety, hyperarousal, depression and nightmares, which Dr Mithoefer said is "twice the relief" that patients can expect through other treatments.
Eighty percent of the patients who were treated in the early 2000s reported that they continued to have minor or virtually no symptoms from one to five years after the therapy.
Rachel Hope, who was raped repeatedly when she was four years old, told CNN she suffered panic attacks, anxiety, insomnia and bleeding ulcers.
"I started having these outrageous flashbacks and body memories," she said.
"The first time, I thought someone slipped me a drug. Because it would be these unstoppable, full-body blackout memories, and people would tell me later, 'You were just screaming for an hour.'"
She tried every known form of therapy and was hospitalised several times before participating in the Mithoefer's trial. Within weeks she said 90 percent of her symptoms had disappeared.
Now Dr Mithoefer has started treating military veterans, police officers and firemen.
Professor David Forbes, the director of the Centre of Posttraumatic Stress at the University of Melbourne, told ninemsn that the research is promising, but it's not necessarily the magic solution to PTSD.
"It's important to acknowledge that we have very solid evidence around psychological therapies called trauma-focused cognitive behaviour therapy," he said.
"These treatments have been shown to be effective across trauma-affected populations, whether they be sexual assault survivors, military veterans or traumatically injured patients."
While more research needs to be done before MDMA is introduced as a mainstream therapy, Professor Forbes said it's unlikely to become the go-to treatment.
"It may well be that for a small number of people who haven't responded to psychological therapy, that finding other ways to assist them to do so may be helpful," he said.
"But we're dealing with a drug where the parameters are less known in terms of its impact. I caution strongly against throwing out or getting distracted from what we know works."
The challenge now is for PTSD sufferers to gain access to trauma-focused cognitive behaviour therapy.
"The degree to which it is actively practised in the community is limited," Professor Forbes said.
"Our biggest challenge is getting trauma-focused psychological behaviour therapy out there and utilised."
The research was published in the Journal of Psychopharmacology.