Antibiotics for Canine Ear Infections

When your dog starts pawing at his ears, shaking his head and seems uncomfortable, chances are good that he has some type of ear infection. Though usually not initially caused by bacteria, many ear problems in dogs develop secondary bacterial infections. For this reason, treating your dog's ear infection will likely require the use of antibiotics from your veterinarian.

Topical Antibiotics

Because you apply them directly to the problem area, topical antibiotics, in the form of ear drops, are the mainstay of treatment for most ear infections in dogs. In general, the ear drops your veterinarian will prescribe for your dog include a steroid to help calm inflammation, an antibiotic to fight bacteria and an anti fungal ingredient to combat yeast.  Common antibiotics used in ear drops for dogs include neomycin, gentamicin and polymixin B. For uncomplicated ear infections, dogs typically require one to two weeks of treatment with ear drops, while more severe infections may require a month or more of topical treatment plus systemic antibiotics.

Systemic Antibiotics

These are antibiotics that dogs take by mouth or receive intravenously in the hospital.  Typically, veterinarians reserve systemic antibiotics for severe ear infections or infections involving the middle ear. The antibiotic your veterinarian chooses is based on a number of factors, most importantly the effectiveness of the drug in treating the current infection. In order to determine which antibiotic will be most effective, your veterinarian will do a bacterial culture and an antibiotic sensitivity test on samples from the infected ear. In general, the oral antibiotics that veterinarians use most commonly for ear infections include amoxicillin-clavulanic acid, cephelexin and other cephalosporins, floroquinolones and sulfonamides. Because it is difficult for most antibiotics to reach the site of the ear infection, veterinarians almost always combine systemic antibiotics with topical ear drops.