My dog is chewing his feet what should i do?

i have took him to the vet!! should i get a second opinion? help!!
Update: the vet said he had allergies and the allergy shots didn't help he has been on them for 1 year now
Update 2: i am in to the vet about 1 time a week and calling almost every day i am concerrned for my dog he is 6 years old and he's feet are sore and bleeding he is also limping! do i need a second opinion?
10 answers 10