When a bitch gives birth and nurses, pheromones are released that are believed help to calm pups and increase the bonding process, and dogs recognize these pheromones throughout their lives. The pheromones are synthetically manufactured to mimic the pheromones that a dog would release naturally.
Initially we had the DAP (Dog Appeasing Pheromone) adapter which was a device that you plugged into the wall (much like a mosquito preventer) and this would help the dog to relax. The problems with this was that it was only effective when the dog was in the room! In the UK this may have been more useful as on average the area covered is much smaller and there is less likelihood, given the weather, that doors to outside would remain open, thereby making the use of the DAP more effective.
About 4 to 5 years ago a pheromone collar was introduced, which looks much like a flea collar that is placed around the neck and works for a month. If the dog goes for a swim or gets wet while wearing it, then it lessens or loses its effectiveness.
We may not be certain how our dogs experience stress but one thing for sure is that an emotional or traumatic effect can significantly impact on their lives and anything that can help lessen this, should, in my option be made use of.
My own experience with these collars is that they really do help and it is one of the tools I will often bring in to assist the dog. The use of same is not going to change your dogs behaviour overnight, but they will help your dog to relax, which will make it easier for the dog to cope with any behaviour modifications that are undertaken or make the dog less stressed when travel etc, is involved.
In the case of a dog that is travelling for example, what the owner needs to do to assist the dog to cope, is to desensitize the dog to the crate being used first and then the collar will have maximum effect. The same would apply to a dog that was going to be left in a kennel while the owner was on holiday – first get the dog used to being in the new location and also away from the owner, and the addition of the pheromone collar will offer a far greater benefit.
In behaviour modification such as separation anxiety, reactive behaviour or any other number of problems, the modifications to change the behaviour need to be done at the same time and yes, the collar will help the dog to cope with the changes.
Another point is that in some cases the use of a pheromone collar to help with excessive fear for example, could be likened to giving a disprin for a migraine headache - it is simply not the right tool for the job. Many dogs with excessive fear need to have stronger medication to assist them.
If your dog does have behaviour problems, or is nervous or fearful, or is going to be travelling, your first step should be to discuss the situation with your vet who will put you in touch with a registered behaviourist and the vet will prescribe the medication the dog should be using and decide if more than a pheromone collar is required.