U.S. Dept of State
U.S. travelers warned about counterfeit pills containing fentanyl in Mexican pharmacies

The State Department warns U.S. travelers that counterfeit pharmaceuticals available at pharmacies in Mexico—sometimes represented as OxyContin, Percocet, Xanax and others—may be tainted with deadly doses of fentanyl and methamphetamine. Since counterfeit medication is common, U.S. citizens are urged to exercise caution when purchasing medication in Mexico, to consult with a medical professional, and to only buy from reputable establishments.