I don't know but have increased like doubled the amount I give him in a bad storm and he has had no adverse effects. He is a large black lab and I give him 4 in a normal storm. They do work very well. They work the best if we give them to him when the storm is coming in not after it is here.

I have an 80 pound dog, and I don't notice much of a difference with his behavior. If anything, it is slight for 3-4 hours.

I have 2 small breed dogs, a 17lb Chi-On (Chihuahua Papillon mix) & a heavy 20lb Shi-Poo (Shih-Tzu Poodle mix). I give them 1 full chew before storms or fireworks start. It seems to help. I would suggest you start with 1 chew then wait an hour & see if it has an affect on your dog. If you don't notice enough of a change give the dog another chew. Then check again after another hour. Be sure to do this a couple hours before the storm or fireworks start so that when they do start your dog has already calmed down. If the storm continues for an hour or more give 1 or 2 more chews (or fireworks if you have multiple fireworks happening in your town like I do. Multiple subdivisions have their own fireworks so it can aggravate the dogs for an hour or 2) based on what you observed in the 1st hour after the initial chew, if it worked give 1 more chew or if you needed to give a second chew at the 1 hour mark then give 2 more chews. Hope this helps.

fish oil can help calm him

Hi, Please see below for the directions. Up to 50 lbs: 1 chew daily.51-100 lbs: 2 chews daily.Over 100 lbs: 3 chews daily.Product can be given daily or on an as-needed basis. It is safe to double or triple the dose in times of increased stress. Thanks,