By now, you’ve likely heard about people wanting to use animal ivermectin for various COVID-related issues, such as treatment and prevention. The FDA has approved ivermectin for use in people for head lice, intestinal strongyloidiasis, onchocerca volvulus, and rosacea inflammatory lesions. However, there is no FDA-approved antiviral use.
Despite that many doctors are starting to prescribe it for COVID-related indications at doses significantly higher than approved doses. According to the NIH, there is not sufficient evidence either for or against the use of ivermectin for COVID, because published studies have contradictory results and significant limitations in study methods.
There has been in vitro evidence of efficacy against SARS-CoV-2 in cell cultures, but based on pharmacokinetic and pharmacodynamic studies, obtaining effective plasma concentrations would require doses up to 100 times higher than approved human doses (1). At those high doses, ivermectin has the potential to cause adverse effects, including seizures and death. Therefore, use of ivermectin in COVID is controversial, with some physicians using it only as a last-ditch effort when all other therapies have failed.
While the jury is still out on whether human-approved ivermectin has a place in treatment of COVID, we clearly know that it is not recommended for people to use veterinary forms of ivermectin. Among the reasons this is problematic are concerns about accurate dosing and toxicity from inactive ingredients. While veterinary professionals are aware of these problems, convincing the public can be more difficult.
The following resources can be used to help educate your clients and address their questions.
- CDC poster: The CDC has designed an informational poster that can be printed and posted in your practice. You can access this at https://www.fda.gov/media/151853/download
- FDA FAQ: The FDA has created an FAQ document about ivermectin and COVID at https://www.fda.gov/animal-veterinary/product-safety-information/faq-covid-19-and-ivermectin-intended-animals
This month’s column is from Lauren Forsythe, PharmD, DICVP, FSVHP.