The exterminator company should be able to tell you if it will be harmful to your dog(s). One that my boyfriend's parents use is TERMINIX - we also used them at my former job before I moved which was at one of the largest corporations in the US. They must be doing something right!
Plus, with them, if you see any bugs withing a few days after they spray, they'll come back and re-spray for free. But it's something I believe you're supposed to have done once a month (that goes for all of the companies)