I am not a scientist, but here is what one research paper presumes:
The exact mechanism to which this effect can be attributed to is yet to be validated, but the speculated method is inhibition of importin ?/?1 mediated transport of viral proteins in and out of the nucleus.4 Importins, a type of karyopherins, exemplify a major class of soluble transport receptors which are involved in nucleo-cytoplasmic transit of various substrates (Fig. 1).5 The speculated inhibitory action of ivermectin on importin ?/? mediated transport system
First off, ivermectin is perfectly safe for humans. It’s been used around the world since the 1970s as an anti-parasitic medicine. It’s not just for cattle. Preliminary studies showed that ivermectin has some benefit in preventing some of the really bad COVID symptoms.
Now for the kicker. Unfortunately, no double-blind large scales studies have shown any significant benefits for taking ivermectin to prevent hospitalization or death from COVID.