We have 2 thundershirts that we use for fireworks and thunderstorms. Pebbles does not do well with fireworks and it seems to really help her this time of year. Bogey is very fearful of thunderstorms. It's helpful for him but only if I put it on him well before the storms start and I also give him a Benadryl too. I hope that it will help with your rescue. I've also used Anxitane in the past which is from your vet but it really didn't help all that much so we stopped using it. When my vet suggested trying it he said that it's either very helpful or doesn't help at all. For Bogey I had much better results with the Thundershirt and Benadryl as needed. Maybe you could ask the vet about the Anxitane and get his opinion. It dos take a while for it to begin working and is not an immediate fix to the issues. If I recall I had to use it for several weeks and since I was hoping that it would help used it for about 6 months before discontinuing use.
Virbac Animal Health — ANXITANE® (L-Theanine) Chewable Tablets | United States
I forgot...Welcome to YorkieTalk