I will share with you some of the things I have learned about allergies relative to my own dog, Coleene. Coleene was born in a puppy mill and aside from some other problems, suffers from allergies which are manifested in dogs as skin problems. Ear infections, skin infections, licking, biting, etc.. Coleene is now 4 years old and has constantly been treated for ear infections (yeast and/or bacteria) and for Staph infections, usually on her belly. the Staph gets treated with oral antibiotics. You can clean out the ears at least once a week with whatever fluid your vet recommends, and let him/her show you how to do it. My vet recommends Virbac Epi-Otic, and most recently Virbac Cerulytic, which is a bit oily.
The information my vet gave me on food allergies is that they are most commonly caused by horse meat, beef, pork, milk, eggs or fish. 70% of the dogs had been eating the offending food for over 2 years. What you have to is put the dog on a hypoallergenic diet (available from the vet) for 10 weeks. No other food, treats or supplements must be fed. Once the pet is symptom free you add one new food or ingredient at a time and see if any allergies develop within a week. So, you would probably want to buy a small bag of a new food, do a slow change over (mix foods gradually) and see how that goes. Some pets will not tolerate any commerical diet, so you must formulate a balanced hypoallergenic diet.
With Coleene, I went through all this and it didn't help, so I had her tested for allergies (a simple blood test) that is submitted to Spectrum Labs. www.vetallergy.com It is a patented "Spot" test for canines, felines, and equines. This test does not test for food allergies, and it shows total reacting allergens (except foods and Staph). You get a nice report booklet that tells you exactly what the dog is allergic to (24 things for Coleene) and if you choose to get allergy shots, the lab prepares the serum which you inject sub-Q at specific intervals. You can do this at home. The initial span of time is about 6 months (we have a few months left to go) and then there is annual maintenance. The booklet gives you other information about allergies in general, how to cleanse your environment, and what to expect during treatment.
One other thing my vet said to try was giving Coleene (100 lbs) 2 tabs (20 mg) of Cetirizine HCl (antihistimine) daily. I buy generic at Sam's, but the trade name is Claritin (plain Claritin, not Claritin D). This *has* helped with her allergies.
Now, a BIG disclaimer: I am a layperson, not a medical professional of any sort. This information is provided as historical information of my own experiences, not as recommendations for treatment or medical advice. Please do not take it as such. I hope that it is helpful to some,and that you may have discussions with your veterinarian or other health professional regading any advice you seek. I cannot guarantee the accuracy of this information, and I am sure there are differing viewpoints on everthing I have said. Again, this is simply historical information about my experiences.
Thank you all, and good luck!
Darla