Twreet from the fda warning people not to take it, and yet celebrities like joe rogan have been talking about taking it. you see this tweet. you are not a horse. you are not a cow. seriously, stop it. doctor, how did this become so popular? is there any research that points to it being effective? >> it's hard to figure out. i took ivermectin in 2014 with a team of doctors and nurses in haiti and on a relief trip. we were exposed to scabies in a significant way. ivermectin is a great drug. it won the nobel prize in between. it treats scabies, river blindness, large animals, to deworm them. we d...