Take your dog to the vet! If you can't, call the vet and explain to the vet what pill he ate and what you have already given him, and ask them to further advise you.
My dog ate one blood pressure pill. Linsinopril 5mg. I gave him some 3% peroxide and I don't think he threw up yet. It has been about 45 minutes since he ate it. Not sure what to do?