We have a 5 year old white lab who has always been very skittish. Our vet recently prescribed anti-anxiety medicine. While checking online, I discovered the Thundershirt and decided to give it a try. Whenever we notice that she is becoming nervous or know of a situation that will make her nervous, we put the shirt on and within 10 minutes we see a noticeable difference in her demeanour. We will not be getting a refill on the medication as we find that the shirt works GREAT!!