Anti-depressants are approved after a few weeks of study, and people use them for years without safety concerns. People have taking 10 times the dose of regular ivermectin without harm (https://pubmed.ncbi.nlm.nih.gov/12362927/). I guess we are in slightly uncharted waters with ivermectin, but there is no evidence from the people who chronically prophylax for covid that regular dosing has caused them issues.

And ivermectin is safest of the current covid treatments, so I find it hard to accept that we shouldn't use it because of safety concerns (for comparison, since 1992 the pharmocavigilance database shows less than 1 death per year from ivermectin, where Remdesivir has 500+ deaths, vaccines has over 2000 deaths with only months of usage).