LITTLE ROCK, Ark. (AP) — Several inmates at a Northwest Arkansas jail say they weren’t told a medication they were given to treat COVID-19 was actually an anti-parasite drug health officials say should not be used to treat the coronavirus.

Three inmates at the Washington County jail told The Associated Press they didn’t know they were given ivermectin until its use was revealed last week.

The American Civil Liberties Union of Arkansas has said it’s heard similar complaints from other inmates.

The state Medical Board has said it’s opened an investigation following reports of the drug’s use at the jail.