Ecstasy—or something posing as it—has been blamed for the deaths of two young British club-goers, with at least 20 more party-goers hospitalized after an all-night dance marathon in London. The exact cause isn't yet established, and reports are vague: the British press variously blames heat stroke, dehydration, and heart failure. "Death by Ecstasy" has been tabloid fodder for so long now that we tend to either take it for granted, or assume they got it wrong: the UK's most famous example was in 1995 with the hugely publicized case of Leah Betts, an 18-year old who fell into a coma and died after taking Ecstasy. X was also blamed for 6 deaths due to excessive body temperature in Florida recently. The Florida X turned out to be PMA (paramethoxyamphetamine) or a similar derivative. Some of these knock-off drugs mimic the chemical composition of X, but the effects can be vastly different. Science has claimed both that X harms your brain—and that those tests were wrong, and it's relatively harmless. Then there's the question of what’s really in the stuff sold. All kinds of alternative chemicals show up in studies of purported MDMA. Professor David Nutt, a former UK drug policy adviser who was fired for his controversial views, calls for a program allowing club-goers to test their ecstasy without fear of arrest. Predictably, this is yet to be adopted. Drug policy experts tell Addiction Inbox that surveys show young club drug users to be remarkably undeterred by this chemical lottery—even given prior knowledge that what they’re taking isn’t MDMA. And if you don’t care what drug you take, then all the educational campaigns in the world won't save your heedless butt.