Can I Use Over-the-Counter Penicillin if my Horse is Sick?

Can I Use Over-the-Counter Penicillin if my Horse is Sick?

Only administer antibiotics in consultation with a veterinarian.


Q. Is it okay to administer over-the-counter procaine penicillin to my horses if they are sick or I suspect they have an infection? It’s inexpensive and available at my feed store.

Via email

A. Antibiotics should always be administered in consultation with a veterinarian! Although procaine penicillin is currently available over-the-counter at the feed store, the increased number of antibiotic-resistant bacteria—which can infect all species, including humans—means that fewer and fewer effective antibiotics will be available to help us fight these infections in the future.

It is imperative that antibiotics only be used sparingly, and your veterinarian is the best person to assess whether your individual animal will benefit from antibiotics. In many cases, antibiotics are not needed and their administration only increases the number of resistant bacteria in our world

In addition and in rare cases, procaine penicillin can cause a dramatic physical reaction in horses. The cause of these reactions is not clear and it is impossible to predict which horses will react in this way. When such reactions occur they are usually short in duration, but create a very dangerous situation for anyone nearby and for the horse himself. A veterinarian is the best person to handle this situation.

About the Author

Mary Robinson, VMD, PhD

Mary Robinson, VMD, PhD, is a lecturer specialist at the University of Pennsylvania School of Veterinary Medicine (Penn Vet), and is the co-director of the Equine Pharmacology Laboratory at Penn Vet's New Bolton Center, as well as the acting director of the Pennsylvania Equine Toxicology and Research Laboratory. Dr. Robinson earned her veterinary degree, and her PhD in pharmacology, from the University of Pennsylvania.

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