Ivermectin is prescribed by body weight, but you can go to a veterinarian and tell them your cat or dog has parasites and get it. That's if you can't get it from your doctor. if you go to your doctor don't tell him you want the ivermectin for covid, tell him you want it for parasites. Best chance that you'll get it! if you're getting it from a veterinarian make sure that you adjust the dosage to your body weight. Usually about 3 a day for about 10 days is the protocol.