I have had experience with promeris and have been using it on my boxers as has my sister-in-law for several months. Those who are familiar with boxers know they are allergic to almost anything, and I always wonder what they will get into next. I can honestly say I have had no problems at all. However, I also read the packaging and talked to my veterinarian on the correct way to give it as well as what side effects had been seen in trials. don't we owe it to our dogs to ask these questions prior to usage??? Since it is made of different chemicals than the other flea and tick medications it does need to be treated with more care. My vet stated the biggest problem as stated by Fort Dodge was lethargy IF ingested. I made sure I put it on them and then turned them out for a couple hours. As a precaution my vet recommend not putting several dogs together in a small space as naturally they would probably come into contact or lick another dog and ingest it. It seems to me much of this is common sense. Is it possible with this many big dogs that they did lick it off of each other? As far as the smell goes, I don't think the smell is any worse than any other product I have used, but like dogs some of us are affected differently than others by smells and chemicals.