Comment by honksillet

I would be surprised if the dose would have to be "much, much" higher. When treating lice or scabies you need to give patient so much that a significant amount is eliminate through the skin. Enough to kill complex multicellular organisms. If I recall, the primary method of elimination of ivermectin is via the liver in the stool (and not via the skin). I wouldn't expect a dose of Ivermectin used to fight COVID to be higher than the dose used to fight, say, scabies. However it would make sense that you would have to take multiple doses over a much longer time to maintain a steady state in the blood stream.