This one makes our stomachs hurt. According to a new report published online, drug addicts who are running dry on painkillers like Oxycontin and Vicodin are turning to over-the-counter Immodium, an anti-diarrhea medication, for a high.

So how does this work, exactly? While it’s safe to take up to four capsules of Imodium a day, addicts are swallowing hundreds of pills at a time, which causes the active ingredient loperamide to enter the central nervous system and deliver that high. (Loperamide usually slows down the digestive track to stop diarrhea.) The effect is also toxic to the heart: Two case studies report addicts overdosing on the drug and dying, despite receiving emergency medical treatment.