While levoquin can be used in dogs, generally speaking, ear infections require topical treatment (ointment you put in the ear after cleaning it) rather than oral medications. The reason is that oral antibiotics cannot penetrate very well into the ear canal where the infection is unless there is some abrasion of the skin within the ear canal.
Whether it would be effective treatment for an ear infection also will depend on what type of infection is present. The most common type of ear infection in dogs is caused by a yeast organism called Malassezia and levoquin would not have any effect against this organism. Certainly there are bacteria that can cause ear infections in dogs as well that would respond to levoquin if the drug can penetrate into the canal.
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