Mississippi health officials are pleading with residents not to take a medicine meant for cows and horses as an alternative to getting the COVID-19 vaccine.

In a state with the nation's second lowest rate of vaccination against the coronavirus, a jump in the number of calls to poison control prompted an alert Friday from the Mississippi State Department of Health about ingesting the drug ivermectin.

Initially, the department said that at least 70% of recent calls to the state poison control center were related to people who ingested a version of the drug that is formulated to treat parasites in cows and horses. But it later clarified that ivermectin-related calls were actually 2% of the total calls to the state poison control center, and 70% of those calls were related to people who took the formula intended for animals.

Ingesting the drug can lead to a rash, nausea, vomiting, abdominal pain, neurologic disorders and potentially severe hepatitis requiring hospitalization, according to the alert written by Dr. Paul Byers, the state's top epidemiologist.

Byers said that 85% of the people calling after using ivermectin had mild symptoms, but at least one person has been hospitalized due to ivermectin toxicity, according to the Mississippi Free Press.

The FDA is also urging people to stop

Ivermectin is sometimes prescribed to people for head lice or skin conditions, but the formulas are different for humans and animals.

"Animal drugs are highly concentrated for large animals and can be highly toxic in humans," Byers wrote in the alert.

Given that cows and horses can easily weigh more than 1,000 pounds, and sometimes more than a ton, the amount of ivermectin meant for livestock would not be suitable for a human who weighs a fraction of that.

The Food and Drug Administration has also weighed in, writing in a tweet this weekend, "You are not a horse. You are not a cow. Seriously, y'all. Stop it."

The tweet included a link to information about the approved uses of ivermectin, and why it should not be taken for COVID-19 prevention or treatment. The FDA has also warned about the differences in ivermectin formulated for animals and humans, noting that inactive ingredients in the formula meant for animals could cause problems in humans.

"Many inactive ingredients found in animal products aren't evaluated for use in people," the statement from the agency said. "Or they are included in much greater quantity than those used in people. In some cases, we don't know how those inactive ingredients will affect how ivermectin is absorbed in the human body."

Health officials urge vaccines as a proven prevention method

The FDA has not approved ivermectin to prevent or treat COVID-19, but the vaccines have been proven to reduce the risk of serious illness or death dramatically. On Monday, Pfizer's COVID-19 vaccine became the first to receive full approval from the FDA.

"While this and other vaccines have met the FDA's rigorous, scientific standards for emergency use authorization, as the first FDA-approved COVID-19 vaccine, the public can be very confident that this vaccine meets the high standards for safety, effectiveness, and manufacturing quality the FDA requires of an approved product," acting FDA Commissioner Janet Woodcock said in a statement.

Both the Moderna and Johnson & Johnson vaccines remain available under emergency use authorization. The FDA is also reviewing a request from Moderna for full approval, and a decision is expected to come soon.

Public health officials are hopeful that full approval will boost confidence among those who have been hesitant to get the vaccine so far, something that Woodcock acknowledged Monday.

"While millions of people have already safely received COVID-19 vaccines, we recognize that for some, the FDA approval of a vaccine may now instill additional confidence to get vaccinated," Woodcock said.

Mississippi State Health Officer Dr. Thomas Dobbs urged people to work with their personal doctors to get vaccinated and get the facts about ivermectin in a Zoom call last week.

"This is medical treatment. You wouldn't get your chemotherapy at a feed store," Dobbs said. "I mean, you wouldn't want to treat your pneumonia with your animal's medication. It can be dangerous to get the wrong doses of medication, especially for something that's meant for a horse or a cow. So we understand the environment we live in. But it's really important if people have medical needs to go through your physician or provider."

Another example of misinformation around COVID-19 treatments

The misinformation surrounding ivermectin is similar to earlier in the pandemic when many people believed without evidence that taking the drug hydroxychloroquine could help prevent COVID-19. Studies later concluded that there was not evidence that hydroxychloroquine helped in preventing the disease.

"There's a lot of misinformation around, and you may have heard that it's okay to take large doses of ivermectin. That is wrong," according to one FDA post.

The rise in use of ivermectin comes at a time when the delta variant is driving a surge in cases across the country, including in Mississippi, where only 36.8% of the population is fully vaccinated. The only state with a lower vaccination rate is neighboring Alabama, with 36.3% of the population being fully vaccinated.

More than 7,200 new cases and 56 new deaths were reported in the state on Sunday. This latest surge in COVID-19 cases led the University of Mississippi Medical Center to open a field hospital in a parking garage this month.

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