Hello, my name isXXXXX and I have over 20 years of experience as a veterinarian.
I'm sorry to hear that your fellow OB1 is itchy.
In combination fatty acids and antihistamines work synergistically, much better than either one alone, so you may want to try both together.
You can try:
1) Benadryl (diphenhydramine only don't use the combination products with acetaminophen or decongestants as they can be toxic) at 1mg to 2mg per pound or one 25mg capsule for a 22 pound dog orally every 8 hours.
OR 2)Claritin (loratidine) at 5mg to 10mg per 25 pound dog once or twice daily.
OR 3)Hydroxyzine at 1mg per pound orally every 8 hours.
OR 4) Chlorpheniramine at 4mg to 8mg per dog once or twice daily.
Some dogs do better on one antihistamine rather than another.
You'll have to see which one works. Give the one you pick a week to 10 day trial and if it isn't working try another. Be aware antihistamines can cause sleepiness or hyperactivity in some dogs. These side effects do wear off with repeated use.
Omega-3 fatty acids are fish oil products. 3V by DVM or Derm Caps ES are good brand name products. Use the high end of the dosing schedule for your pup's weight.
I understand your reluctance to continually use steroids.
Another option if the antihistamines and omega 3's aren't enough is a product called Atopica. It suppresses the immune system a bit so it decreases allergic symptoms but it doesn't have as many harmful side effects as systemic steroids. If you are interested discuss this medication with your veterinarian as it is a prescription.
Cool water baths with an oatmeal shampoo or chlorhexiderm shampoo (which is antibacterial and antifungal) and a conditioner with an antihistamine may also help. The water rinses off allergens and the cool temperature soothes itchy skin.
Best of luck with your fellow, please let me know if you have any further questions.