A reasonable, responsible government that actually cared about people's lives would not be screaming "HORSE DEWORMER, HORSE DEWORMER!"
A reasonable, responsible government would be saying exactly this:
"Even though ivermectin has not been approved by the FDA to treat covid-19, there is still some evidence to suggest it can help reduce the severity and duration of illness. If you attempt to use Ivermectin formulated for large farm animals, make sure to reduce the dosage accordingly to adjust for human body weight so you do do not overdose on medication."
But no, they started screaming, "HORSE DEWORMER!!!"
I hate these people.
I'm 100% okay with using the metric of "it's safe for a horse to eat" as a judge of whether or not it's safe for me to eat. The chances of me having a horrible fatal reaction to some filler materials and flavoring (which is probably food grade flavoring, anyway), is miniscule as long as the dosage is correct.
You trust your math a lot more than I do. I have a background in chemistry, and there is no way in hell I'd trust myself to do the kind of chemical mathematics that you're attempting, even with my background in the field. But I'm not the one who is carrying your risk.