cronic ear infection

Question
my Yorkie has had cronic ear infections for over a year. Two cultures both ecoli--escherichia.
3-antibiotics-zeniquin 25mg---simplicef 100mg--metronidazole.
drops--tobramycin and bartril otic
2 different ear rinse.
My Yorkie is 7 years old, constant shaking licking scratching and bad odor from ear. At one time his canaln was swollen almost shut.
Please advise and thankyou very much

Answer
Ear disease results from some type of skin disease.  It is most often associated with environmental allergens or food allergens. Often a short course of a high dose seteroid is given to decrease the inflammation in the ear. In many cases if the skin disease is controlled, the ear infection will be controlled also.  In addition, with the length of your dog's disease, it wouldn't surprise me if the dog's eardrum was ruptured and that there is also a middle ear disease.  Has your vet checked for otitis media?

Giving antibiotics by mouth has been shown in numerous studies to have little effect in external ear disease.