It seems lately that ivermectin has been in news pieces more often than before, becoming a political football discussed and extolled by street corner and legislative non-medical preachers of the medical word as a miracle for prevention and/or treatment of SARS-CoV-2 infections. It is approved and used for certain parasite infestations by roundworms or nematodes (NEM-ah-toads) (not frogs), and skin parasites like head lice and scabies. It also can be used topically for the skin disease rosacea and eyelid inflammation, blepharitis. It is on the World Health Organization’s list of Essential Medicines.
It has proven to be a godsend for the roundworm disease of river blindness or onchocerciasis, lymphatic filariasis, which produces a disabling and grotesque elephantiasis of limbs, strongyloidiasis, and ascariasis. All of these are serious and potentially devastating and deadly diseases. They exist more in tropical climates, so we are not very familiar with their miseries. Ivermectin can also treat head lice topically, and another mite that causes itch, called scabies. It has been known as “the itch” over the centuries, and can last indefinitely. One gentleman I saw so infested had had it for 7 years. And he “had had” it.
The common mechanism of the drug’s action is to bind to certain channels in invertebrate nerves and muscles which conduct chloride (you remember, the cl- symbol from chemistry?), to block them, causing paralysis and death. If humans take the established dose, ivermectin can’t get into brain tissue to cause serious adverse effects. But if people lack the “horse sense” to NOT take a veterinarian sized dose, it can penetrate their brains to cause central nervous system depression, impaired walking, coma, and death, as well as other reactions.
Ivermectin was discovered by Japanese scientist Satoshi Omura of Kitasato University and scientist William Campbell of Merck Drug Company. In 1970 Omura isolated an unusual Streptomyces bacterium from the soil near a golf course in Honshu, Japan. (Doesn’t everyone dig for microbes in golf course dirt?) He sent some to Campbell, who found that the fermentation products or chemicals from the bacterium killed a round worm in mice. Campbell created the word avermectins for the compound group from the prefix a-, not, and vermis, Latin for worm. From the active compounds he synthesized ivermectin. It was introduced in 1981 and by 1986 it was registered for use in 46 countries and administered massively to cattle, sheep and other animals. It was approved for human use in 1988. It was called a wonder drug for treating roundworms in people.
Half of the 2018 Nobel Prize in Physiology or Medicine was awarded to Omura and Campbell for discovering ivermectin, “the derivatives of which have radically reduced river blindness and lymphatic filariasis, as well as other parasitic diseases.” (Uh, but not COVID.)
Since it had a basic mechanism of disabling parasites, researchers in laboratory settings have been experimenting with how it affected other microbes at cellular levels for repurposing. Before COVID, ivermectin was found to have antiviral effects in the lab against single stranded RNA viruses, including SARS-CoV-2. In monkey kidney cell culture it could inhibit the virus from replicating, but at doses much higher than the maximum approved for humans. One such study from March, 2021, proposed that it be investigated to treat COVID-19.
From a recent post on WebMD, a reputable doctor site: “But cells are not people, and subsequent studies have failed to find any benefit. Others have been flagged for fraud. Even the drug company Merck, ivermectin’s manufacturer has issued a statement that there’s no scientific basis for potential anti-COVID therapeutic effect. The FDA warned against its use last March. But the CDC notes that overdose and misuse cases are rising. More than 88,000 prescriptions were written for the drug the week ending Aug. 13, a 2,400% increase over the weekly average pre-pandemic. Poison control centers everywhere are receiving calls about veterinary ivermectin reactions. The FDA resorted to Twitter to issue a warning after several patients were treated or hospitalized for self-medicating with the horse doses. “You are not a horse. You are not a cow. Seriously, y’all, Stop it.”
There are several human studies in progress now, but no results to report. The tragedy is that non-medical people are touting it with NO medical justification, like certain politicians. A recent article in the Winona Daily News cited a La Crosse Mayo doctor, the Wisconsin state lead for the Committee to Protect Health Care, telling one politician, “If you really want to save lives from COVID-19, please stop horsing around and start promoting measures that actually work, like vaccines and masks.”
Ivermectin is a blessing for certain diseases, but not for unproven ones. Judges with no medical expertise, are overstepping their bounds professionally and ethically, by ordering patient treatment with ivermectin, as in Ohio. To close with another Twitter quote: “If you are following the advice from xxx and taking veterinarian ivermectin, please get yourself spayed or neutered at the same time.”
Dr. Bures, a semi-retired dermatologist, since 1978 has worked Winona, La Crosse, Viroqua, and Red Wing. He also plays clarinet in the Winona Municipal Band and a couple dixieland groups. And he does enjoy a good pun.