Ivermectin – What’s the harm?

Infectious Diseases Staying Safe

There is no evidence that ivermectin can prevent or treat COVID-19, and it can cause harm.

In the early days of a pandemic when there are no vaccines or treatments, sometimes we look at existing drugs to see if they might be effective against a new virus.  This is what happened in 2020 with a few drugs, including ivermectin.  Some lab studies from the 2010s suggested that ivermectin might interfere with the protective layer of viruses and during the pandemic, a vocal minority called for this drug to be repurposed against COVID-19.  It was meant to be a temporary measure while scientists worked on vaccines and better antivirals.

Ivermectin is a medication used to treat parasites in both humans and other animals.  It is taken by mouth to treat people with roundworms but can also be applied in a lotion to treat lice or scabies.   For someone with a roundworm infection, ivermectin is usually taken just once, at a dose supported by years of safety data.

Images of roundworms (CDC)

Despite the lack of evidence to support ivermectin as a “cure” for COVID-19, some people continue to take it not as a single dose, as in with a roundworm infection, but continuously, often at doses at least 3 times what is recommended.

Taking more than the approved dose of ivermectin can cause stomach upset, low blood pressure, or even fainting, coma, seizures, and death.  US Poison Control reported 641 calls regarding ivermectin in 2022, an 87% increase from the year before.  One man who took the drug for an extended period ended up on a heart lung bypass machine, but this did not save his life.  He was 34 years old.

The studies early in the pandemic that hinted at a potential benefit were found to be of poor quality or even fraudulent, and four years later we can say with high confidence there is not good evidence to support its use for COVID.

IDSA graphic

Bottom line:  Ivermectin at the recommended dose is an effective treatment for certain parasitic infections but will not prevent or treat COVID-19 and can be dangerous in large doses.

Those Nerdy Girls

Further Reading and Resources

Ivermectin for Covid-19: abundance of hype, dearth of evidence – STAT (statnews.com)

Ivermectin: How false science created a Covid ‘miracle’ drug (bbc.com)

Evidence Still Lacking to Support Ivermectin as Treatment for COVID-19 – FactCheck.org