Warnings Mount Against Taking Livestock Dewormer to Prevent, Treat COVID-19

The Food and Drug Administration (FDA) has turned to social media to again warn people against taking ivermectin, a medication used to treat heartworm in animals, as protection against developing COVID-19, saying it could endanger them.

“You are not a horse. You are not a cow. Seriously, y’all. Stop it,” the FDA tweeted, after Mississippi’s health department noted in August that more than 70 percent of recent calls to the state’s poison center came from people who ingested the drug purchased at livestock supply centers.

On August 26 the Centers for Disease Control and Prevention (CDC) issued a health alert cautioning that “adverse effects associated with ivermectin misuse and overdose are increasing, as shown by a rise in calls to poison control centers reporting overdoses and more people experiencing adverse effects.”

The CDC noted that a recent study found that more than 88,000 prescriptions for ivermectin had been dispensed in the week ending August 13, a 24-fold increase from pre-pandemic prescriptions for the dewormer, which averaged 3,600 prescriptions per week from March 16, 2019 through March 13, 2020.

The FDA issued a press release in March warning against the misuse of the drug intended for livestock after receiving multiple reports of patients who have required medical support and been hospitalized after self-medicating with ivermectin.

Mississippi State epidemiologist Paul Myers, M.D., issued a health alert in August warning of the potential dire consequences of using a medication intended for livestock.

“Animal drugs are highly concentrated for large animals and can be highly toxic in humans,” he wrote. “Some of the symptoms associated with ivermectin toxicity include rash, nausea, vomiting, abdominal pain, neurologic disorders and potentially severe hepatitis requiring hospitalization.”

Poison control centers around the country — including in Utah, Texas, Oregon, Oklahoma, Missouri, Kansas, Iowa and Florida — have reported recent spikes in calls related to ivermectin.

The FDA has approved the use of ivermectin tablets at specific dosages to treat people with intestinal strongyloidiasis and onchocerciasis, two conditions caused by parasitic worms. The drug is also used to treat heartworm in animals, but those dosages, particularly for large animals like horses, can cause severe harm if taken by people.

The agency notes that ivermectin should not be taken without medical supervision and only for approved purposes, even at low concentrations. It also stresses that people should not take medications intended for animals.