These chews are great! My dogs really enjoy the taste. I have 3 dogs and I can give 1 or 2 treats and it works pretty quickly. I do have 1 dog that is pretty big and tends to get real worked up whenever it thunders and I have to give him 6 of these treats. It takes about 30 to 45 minutes to kick in, but most of the time it does the trick for him too.