Both are pretty strong drugs. If an overdose has occurred it can be pretty serious. The toxicity level depends on how much the 60 pound dog has received. I have dosages for both drugs in a drug formulary but I am prohibited from giving doses over the internet. If you're looking to actually give one of these drugs to your dog you'll have to call your regular vet to get a dose. If your dog accidentally ate one of these drugs and you're looking to find out how much would constitute an overdose, again, your own vet has to give you that information. If you're worried about a toxicity you can call the ASPCA Animal Poison Control Center at(NNN) NNN-NNNNor visit their web site at www.aspca.org/apcc. If I have not satisfied your questions or you have further questions, let me know and we'll continue this thread until I've given you the info you're looking for. Best wishes.