A Houston doctor says he is using the anti-parasite medication ivermectin with a combination of drugs to treat COVID-19 patients, despite warnings from federal health officials that it could cause serious harm when used to combat the virus. Dr. Joseph Varon, chief medical officer at United Memorial Medical Center, on Thursday told the Houston Chronicle that he has used ivermectin since the start of the pandemic in all COVID patients. He said he administers a low dosage based on the people’s weight with a cocktail of steroids and vitamins.