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Cellulitis and Drug Therapy

July 1, 2013

Find out why veterinarians use certain combination drug therapies to treat cellulitis.

Ask an ExpertQuestion:

I own a horse that recently has come down with cellulitis. My veterinarian is treating him with penicillin. He started him today on gentamicin. What does the gentamicin do? I heard this could last for three weeks. Is that correct? Any additional information would be appreciated.

For the answer to this question, we consulted Dr. Manuel Himenes with the American Association of Equine Practitioners.


Gentamicin is an antibiotic that is synergistic with penicillin. That means that combining penicillin and gentamicin is more effective than using either one alone. Cellulitis can be a prolonged treatment, especially if the swelling persists. If your horse can be walked, moving helps with circulation and reduces the swelling.

— Dr. Manuel Himenes, member of the American Association of Equine Practitioners.

*AQHA and the provider of this information are not liable for the inherent risks of equine activities. We always recommend consulting a qualified veterinarian and/or an AQHA Professional Horseman.