Ivermectin
Ivermectin is a medication primarily used to treat parasitic infections, particularly those caused by roundworms, in both humans and animals. It functions by paralyzing and eliminating parasites from the body. In veterinary medicine, ivermectin is utilized to deworm various animals, including livestock and pets, and is available in multiple forms. During the COVID-19 pandemic, ivermectin attracted attention as a potential treatment for the virus, leading to widespread public interest and misinformation regarding its effectiveness. However, rigorous scientific studies have shown that ivermectin is not effective in treating COVID-19 in humans, and the drug has not received approval for this use from health authorities like the U.S. Food and Drug Administration. Misuse of animal-grade ivermectin, which is not intended for human consumption, has led to serious health risks and poisoning cases. While ivermectin can be beneficial for treating certain parasitic infections, it should only be used under medical supervision, and patients may experience various side effects ranging from mild to severe.
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Ivermectin
Ivermectin is a medication that is often used to treat parasitic roundworm infections. It is commonly used for human patients, but alternate formulations of ivermectin are used to deworm a variety of farm and domestic animals. During the COVID-19 pandemic, which spread worldwide early in 2020, some people came to believe that ivermectin can combat the COVID-19 virus that causes the disease in infected humans, despite a lack of evidence of its effectiveness and warnings from most medical professionals to not experiment with the drug.
Overview
Roundworms and other parasites may cause people serious health problems. In some cases, particularly among patients with weakened immune systems, untreated parasitic infection may lead to death. When ingested, ivermectin seeks out, paralyzes, and destroys parasites within the body.
In different formulations, the drug may also be useful for deworming animals. Farmers or veterinarians may treat horses, livestock, cats, and dogs with ivermectin. Animal-grade ivermectin may come in forms such as liquids, pastes, or injectable varieties. Whereas ivermectin for human use requires a prescription, animal-grade ivermectin may be obtained more easily, usually at feed shops or online. Animal ivermectin is not intended for human use, and has not been safety-tested on humans.
A human patient who is prescribed ivermectin will likely take it in pill form by mouth, on an empty stomach with a glass of water. Medical experts should determine the proper size and quantity of doses, which depend on the type of infection as well as the patient’s condition, weight, and reaction to the medicine. For some infections, doctors may prescribe topical application of the drug. Some of these infections include head lice and skin conditions such as rosacea.
Patients using ivermectin may experience a wide range of side effects. Common side effects include dizziness, headache, diarrhea, and nausea. Muscle and joint pain are often associated with the medication as well. Most side effects are relatively mild. Rarely, people may also have serious side effects, including ongoing pain, rapid heartbeat, unconsciousness, seizures, confusion, or chest pain. These require immediate attention by a doctor.
Patients undergoing treatment for onchocerciasis, the infection known as “river blindness,” may have a range of side effects. These occur mainly in the initial four days following the treatment as the internal parasites are destroyed. Onchocerciasis side effects may include swollen lymph nodes, eye irritation or blurry vision, fever, or rashes. People may also feel weak or dizzy and should take care when performing sudden movements, including standing after sitting or lying down.
In the early 2020s the drug gained renewed attention as a possible treatment for COVID-19. In 2020 laboratory testing in Australia showed that large doses of ivermectin may be able to destroy the COVID-19 virus. This finding convinced many people in the United States and elsewhere that ivermectin may be a “miracle” drug that could end the coronavirus pandemic. However, the Australian researchers used levels of ivermectin that would be unsafe for humans and performed their tests in artificial settings.
Other studies soon proved that ivermectin did not reduce rates of hospitalization due to COVID-19. In one of the largest studies of ivermectin to date, researchers in Brazil compared outcomes for 1,300 coronavirus patients treated with either ivermectin or a placebo. In March 2022 these researchers revealed that the drug was not an effective treatment for COVID-19 in humans and ruled out its use for that purpose.
By late 2022 no major scientific study had proven the efficacy of ivermectin in treating COVID-19 in humans. Officials continued to warn people that using the drug in that way—particularly forms or quantities of the drug formulated for animals—may be harmful or even fatal. Despite these warnings, some individuals continued to seek out ivermectin to treat COVID-19; misinformation, including many right-wing conspiracies, continued to promote the drug as a safe and effective treatment for the disease. The drug also began to appeal to some people dealing with long COVID, or a continuation of the disease's symptoms after the acute stage of infection.
Bibliography
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“Why You Should Not Use Ivermectin to Treat or Prevent COVID-19.” Food and Drug Administration, 3 Sept. 2021, www.fda.gov/consumers/consumer-updates/why-you-should-not-use-ivermectin-treat-or-prevent-covid-19. Accessed 14 Oct. 2021.
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