[lanicha]

I bath once a week. I don't know where or who told me that I could bath every week since they don't come with much instructions but I believe my vet said I could. However, my yorkie is itching and I can't tell why. It happens at least 4-5 times a day. We use the K9 Advantix every single month on time so we don't think it is fleas, we have searched his body for tics and we don't see anything. He puts his tail in between his legs and runs around real fast to each couch or wall and rubs up against it so that he can stop itching. It's kinda sad because it seems like I can't help him because I don't know what to do. My Petsmart trainer asked how often do I wash him and I said every week. She told me I am probably drying out his skin and that I am not suppossed to wash him weekly more like once a month. There is no way I am going to wash him just once a month but I hope I am not drying out his skin. I really don't think it's dry skin because he scratches his face, by his ear, and his back legs. I don't even wash his face like that for it to be dry skin and I don't think it is ear mites either. I can't tell what it might be, any suggestions?