Boston Doctors Warn Against Use of Ivermectin as COVID-19 Treatment

There has been growing interest of late in a drug called ivermectin for the prevention or treatment of COVID-19 in humans.

At least two dozen lawsuits have been filed around the U.S., many in recent weeks, by people seeking to force hospitals to give their COVID-stricken loved ones the drug for parasites that has been promoted by conservative commentators as a treatment despite a lack of conclusive evidence that it helps people with the virus.

Interest in the drug started rising toward the end of last year and the beginning of this one, when studies — some later withdrawn, in other countries — seemed to suggest ivermectin had some potential and it became a hot topic of conversation among conservatives on social media. On Friday, Green Bay Packers quarterback Aaron Rodgers, who was recently diagnosed with COVID-19, said on the Pat McAfee Show that he has been taking the drug.

So what do we know about ivermectin?

In the weekly series, "COVID Q&A," NBC10 Boston asked three top Boston doctors on Tuesday for their thoughts on ivermectin and whether it should be used to treat coronavirus symptoms in humans.

So what is ivermectin, exactly?

Ivermectin is approved by the Food and Drug Administration to treat infections of roundworms, lice and other tiny parasites in humans. The FDA has tried to debunk claims that animal-strength versions of the drug can help fight COVID-19, warning that taking it in large doses can cause nausea, vomiting, diarrhea, seizures, delirium and even death.

"Ivermectin is a medicine that originally was developed for the treatment of parasitic infections in livestock and pets, basically for veterinary uses," Boston Medical Center's Dr. Davidson Hamer explained. "Eventually it was found to have a very good effectiveness for some relatively unusual parasitic infections, -- at least unusual for the U.S. It's really a great mass dose treatment being used for these diseases."

Does it work against COVID?

The FDA has not authorized or approved ivermectin for use in preventing or treating COVID-19 in humans or animals. Currently available data do not show ivermectin is effective against COVID-19. Clinical trials assessing ivermectin tablets for the prevention or treatment of COVID-19 in people are ongoing.

"It has some activity in tissue culture against SARS-CoV-2, and that led to a lot of interest in testing this for efficacy in patients," Hamer said. "Initially, there was a lot of hype because of some uncontrolled data that came out suggesting that it improved outcomes. They really were not well designed studies."

"Subsequently, a number of randomized controlled studies have been done and they show absolutely no benefit of ivermectin," he added. "But the problem is in the popular press and on social media there's been a lot of people advocating for this, saying this is a great way to prevent disease, to treat disease, and the end result is there's been this incredible run on available stock."

'The hydroxychloroquine of 2021'

"I think ivermectin became the hydroxychloroquine of 2021," said Dr. Daniel Kuritzkes of Brigham and Women's Hospital. "There's now this unshakeable faith in the utility of the drug on the part of some people in the complete absence of any positive data."

"A number of papers have shown given the achievable concentrations of the drug in the bloodstream from appropriate human doses you simply can't get enough drug in to have an effect against SARS-CoV-2," he said. "That's why some people have been using these much higher doses. It's shocking that even here in Massachusetts there was a road sign from a local pharmacy offering ivermectin available for compounding, as though there was any rationale for doing that."

"When the pandemic began and it was bearing down on us and hospitals were filling up quickly -- especially here in the northeast -- it made sense, it was acceptable to try things that might work," added Dr. Shira Doron of Tufts Medical Center. "That's what happened with hydroxychloroquine. What happened, though, in the end is that patients were harmed by a drug that had side effects and didn't actually work. If now we have the infrastructure in place to do clinical trials on drugs that might seem in the test tube, in the lab, to have some efficacy, we can do those in a controlled and safe way and have the answer before we give people unproven therapies."

What are some of the side effects associated with ivermectin?

The FDA said even the levels of ivermectin for approved human uses can interact with other medications, like blood-thinners. You can also overdose on ivermectin, which can cause nausea, vomiting, diarrhea, hypotension, allergic reactions, dizziness, balance problems, seizures, coma and even death. 

"The CDC was showing a very large increase over the summer in the use of ivermectin -- 24 times as high as before the pandemic," Hamer said. "Between July and August 2021 it increased four-fold. And so there's a lot of people trying to get it or have their physician prescribe it, but it doesn't really seem to work and there are some safety issues. Twenty-one people have been hospitalized because of toxic side effects from ivermectin. None have died -- all have recovered -- but four were sick enough to be in an ICU."

"This is something if you use in mega doses is not a safe drug," he said. "People need to realize it doesn't work and it's not safe.'

What are the unintended consequences of people buying up so much ivermectin?

"With hydroxy there was such a run on that medicine that people who needed it for lupus, rheumatoid arthritis had a hard time getting prescriptions filled," Hamer said. "I'm hearing some vets are having trouble getting enough ivermectin to treat the animals they need to treat."

"So there's sort of collateral damage being done by this."

The Associated Press contributed to this report.