Metronidazole
"I took one pill and was so close to gagging, that I called my pharmacy to see if there was another version they sold that including a coating on the pill.  Since there wasn't, I had to come up with an alternative if I was to ever get past the first dose. So I decided to coat the pill myself with peanut butter, which did the trick with helping that little rancid pill get down. I checked with the pharmacist, and he said it was okay to do that.  After I eat, I can still taste it a little, but it's nothing like it was before I coated it."