Our past dog Sam had very bad allergies ( and we had all the expensive testing done and the special diet for 6 months) till she out grew them. The benadryl helped somewhat and the cortisone. The vet also gave (we bought) a special shampoo for allergies that you left on for 10 min. and rinsed off and it worked great. Baking soda (not powder) works good on humans so might it work on dogs? Wish I could help you more.