For what it's worth, there are different versions of ivermectin. Some dosages are designed for horses or dogs. Needless to saw, a horse needs a LOT more of any medication that is also used for a human. A horse weighs 900-2000 lbs.
Medication dosage is usually based more on weight than any other factor. That's why clinical studies for children are usually done well after the dosage for adults has been around for a while. Also why the ongoing studies for COVID-19 vaccines in younger children are broken down into multiple age groups, not just 0-11. I don't have a medical background, but being petite I took the child dose for over-the-counter medications for years after I was considered an adult. For the rare times I needed aspirin, I used children's aspirin because it was easier to adjust the dose down. Pill cutters were that common 20-30 years ago.
Here's a what a Ski Diva who is a physician had to say in response to a mutual FB Friend who was making fun of people using ivermectin. My immunologist ski buddy pays attention to Facebook.
Posted on Facebook in late August 2021 by a physician who is over 65
"Ivermectin has a boatload of science behind it for numerous human medical conditions, and it's gaining data in treatment of COVID. Just like lisinopril was developed for treatment of high blood pressure, now it's used to reverse cardiomyopathy, keep diabetics off dialysis, and even shows potential for a COVID treatment. Can't write ivermection off just yet. The main problem with it is it's a dirt cheap generic that Big Pharma can't control, so less research will be done on https://journals.lww.com/americanth...mectin_for_prevention_and_treatment_of.7.aspx