A supposed cure for autism is dangerous, say an increasing number of doctors, law enforcement agencies, and former customers.

As detailed by Newsy in the video above, the product in the question, either called Miracle Mineral Solution, Master Mineral Solution, or just MMS, has been criticized for its medical claims and rarely discussed side effects.

Proponents and sellers of MMS have touted it as a remedy for a laundry list of health conditions, including autism, cancer, and virtually all infectious diseases. MMS is actually an industrial bleaching solution, sodium chlorite, when mixed with citric acid as instructed. Users of MMS — taken either orally or via enema — have experienced vomiting, dehydration, and possibly even death, as in the case of Sylvia Fink, who died 12 hours after taking MMS in 2009 (an autopsy was inconclusive in finding a concrete cause of death, however).

In May 2015, Louis Daniel Smith, 45, of Spokane, Washington, was convicted of multiple federal charges for having run a business called Project GreenLife that manufactured and sold MMS over the internet from 2007 to 2011.

“This verdict demonstrates that the Department of Justice will prosecute those who sell dangerous chemicals as miracle cures to sick people and their desperate loved ones,” said Principal Deputy Assistant Attorney General Benjamin C. Mizer of the Justice Department’s Civil Division, in a statement at the time. “Consumers have the right to expect that the medicines that they purchase are safe and effective.”

Though Smith was sentenced to over four years in federal prison, MMS can still be purchased online.