Counterfeit pills sold in Mexican pharmacies found to contain fentanyl, heroin and methamphetamine

A UCLA-led study provides the first scientific evidence that brick and mortar pharmacies in northern Mexican tourist towns are selling counterfeit pills containing fentanyl, heroin, and methamphetamine. These pills are sold mainly to US tourists, and are often passed off as controlled substances such as Oxycodone, Percocet, and Adderall.

The pills are available without a prescription—potentially adding to the already high number of overdose deaths stemming from use of those potent drugs in Mexico and the US.

"These counterfeit pills represent a serious overdose risk to buyers who think they are getting a known quantity of a weaker drug," said senior author Chelsea Shover, assistant professor-in-residence of medicine in the division of general internal medicine and health services research at the David Geffen School of Medicine at UCLA.

A preprint of the study, which has not yet been peer reviewed, is available online on the medRxiv preprint server. A Los Angeles Times investigation has also independently corroborated the UCLA researchers' main findings.

The UCLA team reported on 40 pharmacies in four cities in northern Mexico, finding that about two out of three (68%) had at least one controlled substance for sale without a prescription, either in bottles or individual pills.

Counterfeit pills containing fentanyl, heroin, and/or methamphetamine were sold at 11 pharmacies. Of 45 pill samples, nine sold as Adderall contained methamphetamine, eight sold as Oxycodone had fentanyl, and three sold as Oxycodone contained heroin.

"It is not possible to distinguish counterfeit medications based on appearance, because identically-appearing authentic and counterfeit versions are often sold in close geographic proximity," the researchers write. "Nevertheless, US tourist drug consumers may be more trusting of controlled substances purchased directly from pharmacies."