Always good to check with a vet. One of my fosters was put on ear meds (Mometamax) and the next day he did not seem right. He was not responding normally and it occurred to me that he could not hear. I googled and found out that it does sometimes cause them to lose their hearing...took him to the vet and they flushed his ears. Fortunately we caught it quickly and he did not suffer permanent hearing loss. Of course that was a different medication, but just using it as an example.
Hopefully he is just tired.
