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 didn't bring up Joe Rogan, but if he took pills designed for people, then most of my worries about this dissolve. At least those medications only contain stuff tested for and mixed for people.
And if it came from a doctor, then Rogan ostensibly has been cleared medically for these pills by people who know what to look for as far as side effects and interactions.
I don't have a problem with people taking Ivermectin. I worry about people who try to do a complex pharmacological calculation with no real training or expertise in order to take a "safe" amount of ivermectin from a formula that was never intended for human consumption in the first place and contains definitionally confounding variables.
As I've said, I have done these type of calculations before, and they are WAY more complicated than simply dividing by body weight or something. Chemistry is a fickle bitch, and even when you do it perfectly, entropy will work against you.
It just so happens the CDC recommends a 200µg/kg (0.2mg/kg) dose for humans using it to fight a scabies infections.
https://www.cdc.gov/parasites/scabies/health_professionals/meds.html
The Durvet Ivermectin horse paste is at 1.87% concentration and contains 6.08 grams, which means each tube contains .11 grams of Ivermectin. Convert that to mg and you get 110mg.
Since a kg is 2.2 lbs, you can divide .2mg by 2.2 and you'll get 0.09 mg/lb .
If you weigh 180 lbs., that works out to a 16.2 mg dose (multiply 180 by .09), so roughly 6.79 doses in a tube of horse paste.
If you weigh 250 lbs, it works out to a 22.5 mg dose or roughly 4.888 doses in a tube.
It appears the dosage for humans per pound is virtually identical to what's given to horses as there's 5 large notches on the tube labeled 250, 500, 750, 1000, 1250.
There was nothing particularly hard about that calculation and I only took chemistry in high school.
Personally, I'm not taking horse paste and would get it prescribed by a doctor if I really wanted it.