Many of those pills are being traded openly via social media, particularly on Snapchat, the most popular app among U.S. teens. Snapchat has been linked to the sale of fentanyl-laced counterfeit pills that have caused the deaths of teens and young adults in at least 15 states, according to The Partnership for Safe Medicines, a nonprofit public health group. NBC News independently confirmed deaths in 14 of the 15 states and identified five additional states not included in the research.

Source: When one pill kills