A recent study by the University of California (UCLA) concluded that many drugs from Mexican pharmacies are laced with fentanyl, heroin, and methamphetamine. U.S. tourists are often the buyers of these pills, which include counterfeit replicas of Oxycodone, Percocet, and Adderall.
The UCLA-led study reported that two out of three (68 percent) pharmacies in four cities in northern Mexico had at least one controlled substance for sale without requiring a prescription. Prescriptions were also offered in bottles or individual pills.