Drug called ACEPROMAZINE is used as premedication before inducing anesthaesia. It is dangerous to many large breeds, and it can be lethal if given to brachicephalic dogs ( such as boxers, etc ) in normal dose. I use it even with boxers, but in much smaller doses and it never made me an problem. Its only that boxers are "done" with dose wich wouldnt have any effect on other breeds. I use it in premedication combined with ketamine and diazepam.