Ivermectin

Ivermectin is a medication that is often used to treat parasitic roundworm infections and some other parasitic conditions, including scabies. 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 could combat the COVID-19 virus (COVID-19 is the disease and SARS-CoV-2 is the 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 and subsequent clinical trials and medical reviews consistently failed to prove it was an effective treatment for humans.

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 or approved 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 a topical application of the drug. Some of these infections include head lice and skin conditions such as rosacea, which is not a parasitic infection but may be treated with topical ivermectin.

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 SARS-CoV-2 . 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 hospitalization rates due to COVID-19. In an extensive study of ivermectin, researchers in Brazil compared outcomes for 1,300 patients with coronavirus 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. Another similar study led by the Duke Clinical Research Institute enrolled 5,000 participants in a double-blind nationwide study. Its findings, published in 2023, also found no benefit from the drug in treating or preventing COVID-19.

No major scientific study has 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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