Claims about the drug are based on shoddy science—but that science is entirely unremarkable in its shoddiness.
Ivermectin is an antiparasitic drug, and a very good one. If you are infected with the roundworms that cause river blindness or the parasitic mites that cause scabies, it is wonderfully effective. It is cheap; it is accessible; and its discoverers won the Nobel Prize in 2015. It has also been widely promoted as a coronavirus prophylactic and treatment.
This promotion has been broadly criticized as a fever dream conceived in the memetic bowels of the internet and as a convenient buttress for bad arguments against vaccination. This is not entirely fair. Perhaps 70 to 100 studies have been conducted on the use of ivermectin for treating or preventing COVID-19; several dozen of them support the hypothesis that the drug is a plague mitigant. Two meta-analyses, which looked at data aggregated across subsets of these studies, concluded that the drug has value in the fight against the pandemic.