Has he been checked for Malassezia (yeast infection)? It generally presents in the areas you're describing and is usually caused by allergies. You might want to try some fish oil caps to boost the immune system and use a shampoo for yeast. We use Melasab shampoo.

Here's a couple of articles on it, but you can google and find more info. http://www.peteducation.com/article....2+2102&aid=321 and http://www.westiemed.org/health/malassezia/ Chester's never looked as bad as the dogs in these articles, thank goodness. Just VERY red and he's unable to leave it alone.

My allergy dog, Chester, has had two yeast infections and the dermatologist has been the only one to figure it out both times. One vet was convinced he had mange, even though he'd been scraped for that upmteen times over the last 11 years. 30 days of oral meds and baths twice a week with the Melasab shampoo cleared it up, but it took a long time and Chester was in an e-collar for most of that time.

I seriously doubt your dog is allergic to your couch or even your laundry detergent. It's most likely either the grains or the protein source in the food, or external allergens like pollen (there is cedar in the air and other allergens even in the winter) or mold & fungus. We've had cold weather here, but Chester's been flaring for 3 weeks due to the junipers.

I wish you the best of luck!