Ivermectin is used to to treat Onchocerciasis, Strongyloidiasis, Ascariasis, Cutaneous Larva Migrans, Filariasis, Scabies, and Filariasis.
Spend a couple minutes on google and you will realize, all of these are parasitic, most brought on by some form of worm parasite. None are viral or bacterial.
For those that keep quoting studies, here is an interesting read
https://www.theguardian.com/science/202 ... l-concerns
Apparently the single largest study on the subject had the paper withdrawn because the data was essentially fabricated, yet it is continually referenced by those pushing the drug.
If you read farther, studies done in a petri dish show the virus has a low rate of survival exposed to Ivermectin in a petri dish, ie, when there is nothing else in the surroundings. Further studies done in people have had inconclusive results, ie, there was no statistically significant difference between the study groups given Ivermectin and those given a non active placebo after you remove the data from the fabricated study.
In some of the less developed tropical countries, small doses of Ivermectin are perscribed annually as a matter of course to deal with parasites present in the water supply and insect population. The key word there is 'small', for that application dose is on the order of 0.4 mg. The dose typically found in the vet supply stores is on the order of 10x that amount.
Widely used as a worm solution in the vet industry, a vet has to be conscious of the potential side effects. In horses they are expected to be minimal. With dogs as another example, there is potential for serious neurological side effects in dogs. To understand doseage, it's based on the weight of the animal. With horses and cattle, the danger of overdose is minimal, but that doesn't hold true when dealing with cats and dogs.
Have a good friend in the vet business, asked him about it. His response made me chuckle. 'The most serious side effect is neurological, so it doesn't really matter. Those wanting to take Ivermectin for covid are already brain damaged, a little more wont hurt.'