ST. LOUIS (AP) — A doctor for Mercy hospitals says several people have been treated in Missouri emergency rooms after taking the parasite drug ivermectin, even as experts warn of dangerous side effects and a lack of proof that it helps treat COVID-19. Dr. Steven Brown told KMOV-TV that cases of ivermectin toxicity have occurred at Mercy hospitals across the state. Brown is a virtual care physician for Mercy. In addition to the illnesses, Brown says he as seen deaths among people who relied on ivermectin to prevent the virus.