Lifestyle Health Large Study Affirms that Ivermectin Does Not Reduce the Risk of COVID Hospitalization The study follows several others that determined that the medication, which is primarily used as a cow and horse de-wormer, is ineffective as a COVID-19 treatment By Julie Mazziotta Julie Mazziotta Twitter Julie Mazziotta is the Sports Editor at PEOPLE, covering everything from the NFL to tennis to Simone Biles and Tom Brady. She was previously an Associate Editor for the Health vertical for six years, and prior to joining PEOPLE worked at Health Magazine. When not covering professional athletes, Julie spends her time as a (very) amateur athlete, training for marathons, long bike trips and hikes. People Editorial Guidelines Published on March 31, 2022 05:11 PM Share Tweet Pin Email Ivermectin. Photo: Getty The anti-parasitic drug ivermectin was ineffective in reducing the risk of hospitalization for COVID-19, a large study found, echoing the findings of previous studies on the medication. The study further confirmed that while ivermectin has become popular as an alternative treatment for COVID-19 in some circles, it does not work against the virus. In a large clinical trial of more than 1,300 COVID-19 patients in Brazil, half received ivermectin and the others received a placebo to see if it could treat the virus. Researchers concluded that the medication, primarily used as a cow and horse de-wormer, had no effect. "Treatment with ivermectin did not result in a lower incidence of medical admission to a hospital due to progression of COVID-19 or of prolonged emergency department observation among outpatients with an early diagnosis of COVID-19," they wrote in the study, published Wednesday in the New England Journal of Medicine. FDA Warns People Not to Treat COVID with Drug Meant for Livestock: 'You Are Not a Horse' The researchers tried looking at different methods of administering ivermectin, from early on in their infection to later, and found that in both cases it was ineffective. And when the drug was given in the first three days of infection, patients actually fared worse than those who received the placebo. Ivermectin initially came up as a possible treatment for COVID-19 early in the pandemic, when researchers were trying existing medications to see if they could work against the then-unknown virus. One study, a review of smaller trials published in Dec. 2020, indicated that ivermectin significantly lower the risk of death from COVID-19, but was later found to have used flawed data and was retracted. RELATED VIDEO: Aaron Rodgers Confirms He Is Unvaccinated, Says He 'Didn't Lie' When He Said He Was 'Immunized' But interest in the drug, particularly in anti-vaccine circles, took off, with people purchasing ivermectin at horse supply stores to use unregulated. That lead the Food and Drug Administration to put out a strong warning telling Americans not to use it. "You are not a horse. You are not a cow. Seriously, y'all. Stop it," the FDA tweeted in August 2021. "Taking large doses of this drug is dangerous and can cause serious harm." Still, people continued to use ivermectin and demand it from doctors, leading some to sue to allow them to receive the drug as a COVID-19 treatment. Influential people like podcaster Joe Rogan and Green Bay Packers quarterback Aaron Rodgers, both of whom have said they are unvaccinated, also said they took ivermectin when they had COVID-19. The study from Brazil, along with multiple others in the past two years, have all found though that ivermectin has no effect on COVID-19. Dr. Paul Sax, an infectious-disease expert at Brigham and Women's Hospital in Boston who was not involved in the study, told The New York Times that it may be time to stop looking at ivermectin as a treatment. "I welcome the results of the other clinical trials and will view them with an open mind, but at some point it will become a waste of resources to continue studying an unpromising approach," Sax said.