By Maia Anderson

Prescriptions for the anti-parasite drug ivermectin have soared to more than 88,000 per week as of mid-August, up from the pre-pandemic average of 3,600 per week, according to CDC data.

Ivermectin is most often used to treat parasitic worms in animals. It isn't an antiviral, but some physicians have been prescribing it to treat COVID-19.

Gregory Yu, MD, an emergency physician in San Antonio, said Aug. 30 that he has received daily requests for ivermectin from COVID-19 patients over the last week. He has refused the requests, but said he knows some of his colleagues are prescribing it.

The FDA has warned against use of the drug, which is approved only at very specific doses for humans to treat some parasitic worms, as well as some topical formulations for head lice and skin conditions. The CDC warned healthcare providers and the public Aug. 26 about reports of severe illness associated with using ivermectin products to prevent or treat COVID-19.

Some pharmacists have reported shortages of ivermectin and a growing number of people are getting it from livestock supply centers, where it comes in highly concentrated paste or liquid forms.

"People are going to animal feed stores and getting a formulation that's highly concentrated because it's for 1,000-pound animals," said Shawn Varney, MD, medical director for the South Texas Poison Center. "They're opening themselves to great potential harm."

"Everyone wants some cure for COVID because it's such a devastating illness," he added. "I plead with people to stop using ivermectin and get the vaccine because it's the best protection we have at this point. Everything else is risk after risk."