My collie (and every dog I've had) is terrified of thunderstorms and fireworks.  I've tried other anti-anxiety products, and none of them work as well as these, other than Rx drugs that I don't want to use.  As soon as I suspect a storm is coming, I give her a couple of these and she is much calmer. without acting drugged.  Once thunder has begun, she is too anxious to take one, so I suggest giving them ahead of time.  This also works very well if she is given a couple of them before we trim her nails;  she's very cooperative instead of being nervous and pulling back her paws.  She loves the taste, and thinks she's been given a crunchy treat instead of an anti-anxiety wafer, so be sure to keep them out of the dog's reach!