U of S veterinary prof dumbfounded as to why anyone would risk taking livestock dewormer

A University of Saskatchewan veterinary professor is dumbfounded some people are willing to take ivermectin, a livestock dewormer, as a treatment for COVID-19.

SHA says it's seen a few cases of people taking ivermectin with false assumption it treats COVID

Misinformation that suggests the livestock dewormer drug ivermectin can be used to treat COVID-19 has led the Veterinary College at the University of Saskatchewan to change its policy on who it will give a prescription for the drug. (Lone Star Tack & Feed Inc.)

A University of Saskatchewan veterinary professor is dumbfounded some people are willing to take ivermectin, a livestock dewormer, as a treatment for COVID-19.

"My reaction is one, a little bit of disbelief and two, a general sense of concern that people are prepared to put themselves at such significant risk," said Chris Clark, an associate professor of large animal medicine and the associate dean at the Western College of Veterinary Medicine at the U of S. 

There have been false claims the ivermectin treats COVID-19.

Clark said he first heard about these claims about six months ago, but that they have blown up in the last few days, with some livestock feed stores saying they are seeing a spike in requests for ivermectin.

"The drugs are designed for animals that weigh upwards of 500 kilograms. So the risk of overdosing in humans is very high," Clark said.

Ivermectin has been used in veterinary medicine for more than 30 years.

It is predominantly used in livestock species like horses and cows to control both intestinal parasites and some skin parasites.

"It's a very effective drug in those species and has a good safety profile in those species," Clark said, adding the drug is designed to be administered though different routes in animals.

"Some of these drugs are designed to be poured onto cattle hide and are absorbed through the skin. Some are administered orally, some are given by injection," Clark said. "And they should under no circumstances ever be used in humans.

"You'll notice on the label that it says do not use in humans. And it says that for very good reason. And I know it seems impossible to have to say this, but you need to trust what it says on that label more than what some guy said on Twitter or Facebook."

A portrait of a light brown-coloured horse against a blurred background of greenery.
Ivermectin is used to treat parasites in livestock like horses and cows. (dezy/Shutterstock)

The Saskatchewan Health Authority (SHA) has tweeted out warnings about using ivermectin, but in a statement sent to the CBC, the SHA said it has seen a few cases of people who have used the veterinary drug.

"Saskatchewan physicians are concerned about inappropriate requests for the use of veterinary ivermectin in patients," the SHA release said."Veterinary ivermectin is not intended nor approved for human ingestion, and can lead to serious side effects."

The SHA said the best way to reduce the possibility of getting COVID-19, or getting seriously ill if you do get it, is to get vaccinated.

Clark said the vet college is taking precautions so the dewormer doesn't get into the wrong hands.

"Our clients that we know, and know their animals, we will provide them with a prescription which allows them to purchase the product," Clark said.

"If someone just came in through the door and asked for it, we would not be prepared to sell it to them."

There are different forms of ivermectin used to treat parasites, such as intestinal worms or lice, in both animals and humans.

The form of the drug used on humans is on the World Health Organization's list of essential medicines because it is safe, inexpensive and effective — and has proven to be life-saving for treating some illnesses caused by parasites.

But parasites are not the same as viruses. COVID-19 is caused by a virus. 

Some feed stores in Western Canada say they're receiving a deluge of callers asking to buy ivermectin due to misinformation that suggests the livestock dewormer can be used to treat COVID-19 in humans. (Lone Star Tack & Feed Inc.)

Last week, the United States Food and Drug administration reissued warnings about ivermectin in response to a growing volume of misinformation on social media and reports of people poisoning and even killing themselves with it. 

"You are not a horse. You are not a cow. Seriously, y'all. Stop it," said a tweet from the U.S. FDA.

Neither Health Canada nor the U.S. FDA has approved ivermectin as prevention or cure for COVID-19, and no clinical studies have proven whether it can slow or stop the spread of novel coronavirus in humans.

One published study supporting the use of ivermectin as a COVID-19 treatment had to be retracted after concerns were raised about data fabrication, plagiarism and ethical breaches.

"The absolute message is just do not ever take a product, a veterinary product and use it to treat yourself or a family member," Clark said.

With files from Karen Larsen and Sarah Rieger