honestly senior dog food doesnt do anything , have you tested her for enviromental allergies ? it could also be something that shes eating that causes the allergies. Theres only one way to find out if its the food is trying diffrent ones after that check what ingredents they all have the same and start cutting it down fromt here say they all have chicken change to fish ect ect, when we had our boxer we werent sure what the itching was till we found out this was the cause she was allergic to her food so we used seafood for dogs, worked like a charm, Good luck 