My dog is a 14 year old chihuahua mix on grain free food. Been that way for years. I noticed within the last 3 days he’s been itching a lot (to the point it’s starting to be irritating at odds hours in the night) on his chest and mid section. I just gave him a bath in Zymox (medicated) shampoo and leave in condition that I mostly rinsed off. I’m wondering if There are any OTC spray that will help alleviate some of the itching between baths. The only thing that has changed in his environment is the weather/heat between my place and my parents. As we live in different counties.