The Food and Drug Administration designated the drug MDMA, known as Ecstasy, a "breakthrough therapy" for PTSD treatment earlier this month. The designation will expedite the agency's review of the drug, depending on the outcome of a clinical trial to test its effect versus that of standard psychotherapy. Ecstasy is in the DEA's category of Schedule 1 drugs, meaning that it is among substances with the highest potential for abuse, like heroin.

Why it matters: 11-20% of veterans who served in Afghanistan or Iraq suffer from PTSD, per the Department of Veterans' Affairs, and it is this group in particular that researchers hope ecstasy can help.

• "We're in this odd situation where one of the most promising therapies also happens to be a Schedule 1 substance," former Brig. Gen. Loree Sutton said to the Washington Post.
• "This is not a big scientific step ... It's been obvious for 40 years that these drugs are medicine. But it's a huge step in acceptance," David Nutt, a scientist at Imperial College London, told Science.
• One concern is that approving Ecstasy for PTSD will embolden groups seeking to legalize the drug for recreational use, the Post reports.