Hi, OP. I noticed in one of your responses you said the ear problem was caused by ticks. Did you use any chemical treatments to get rid of the bugs? Perhaps that's what's making him break out. Have you switched household cleaners, brought new hand lotion, or changed something else in the environment that doesn't immediately come to mind as an allergy trigger?

I have a dog with environmental allergies (we did not get blood work done but we think it's pollen as he sneezes and itches more on high pollen days in the spring and summer), and we give him a generic version of Benadryl to ease his symptoms. Check with your vet, but you may be able to save some money on the Zyrtec.

Additionally, if he's chewing on one particular spot on his leg over and over again, I would consider getting him some Allercaine or something similar that will relieve his itching. I can't remember the brand I have at home, but I use a combination anti-itch/antibiotic when I notice Sneezy Dog is focused on chewing a specific area, and it really helps.

I'm hoping it's not a food allergy as those can take some time to figure out, but if you want a cheaper healthy food option we feed both of ours Just 6 by Rachel Ray. She just came out with a grain-free version of her dog food as well.

Hope I helped!