lillibirdy, what happened to Gunner also happened to Scrapper. After the cortisone wore off and I stopped the prednisone pills, the hives came back in force. I agree with your suggestion to examine the food ingredients. Apparently, there are a number of food items that can trigger allergies in Boxers and there are a couple of foods formulated expressly for allergic dogs. Natural Balance, especially the duck and potato, and California Natural, I believe are two of them.
Try to observe if the hives get better or worse at any particular time. Scrapper's hives seemed to be worse in the morning when he awoke, but would sort of recede during the day. I took to giving him the benedryl at night before bedtime to ease the itching, although the hives still came.
I also changed his food and washed his fleeces in natural hypo-allergenic soap. Fortunately, the hives disappeared after about five weeks and have not returned. I took to putting a doggie t-shirt on him (gotten at Old Navy) during the day to keep 1) him warm (this was in winter and we thought there might be a chance the hives were a cold sensitivity), and 2) to keep his fur from contacting any outside allergen. I think the T-shirt actually helped a lot, although it's not designed for a male dog's anatomy and we had to pull it up in the back with a rubber band to, uh, allow him room to pee...
This can be a long, frustrating process and I wish you luck in discovering what's giving hives to your babies. I really didn't want to continue with the steroids for a long period of time. On the other hand, the benedryl seemed to have no ill effects (I didn't notice any sleepiness) and I could continue it for some time if need be. Maybe they can outgrow this, we are keeping our fingers crossed for this winter with Scrapper.
doesn't seem bothered by them at all, but we do give Benadryl - and he is 90lbs so we give 2 every 12 hours.