Mexico has said it is already seeing black market or fake versions of molnupiravir circulating for sale, just one week after authorities approved the drug to treat those at risk of severe Covid-19.

The real medication is produced by US pharmaceutical company Merck. But Mexico’s health regulatory agency found versions labelled molnupiravir for sale from an array of companies like “Merit”, “Molaz” and “Azista.”

The agency said that it had no record of any permits for import or sales of those companies’ drugs and considered them a health risk, AP reported.