The vet gave Zen a 6 month prescription of Hills Derma Complete. He loves it but I am not sure if I should continue with it due to what Iām hearing about it. He is going on day 2 with it. Before this he was on Pet Fresh Turkey. He loves that as well too but heās losing hair on his tummy. I canāt afford the $600 allergy test so so donāt know what to do!? Please help. Thanks everyone.