A Novel Treatment for Sarcoids in Horses

Austrian researchers believe that topical application of acyclovir is useful in the treatment of sarcoids. Acyclovir is an antiviral drug that is used primarily in human medicine for the treatment of chickenpox and shingles.

Twenty-two sarcoid-affected horses were referred to a veterinary hospital between 2006 and 2009. Diagnosis of sarcoid was confirmed by clinical and histological examination. Because nine of the horses had more than one lesion, 47 total sarcoids were identified and detailed before treatment began. Sarcoids were treated with a once-daily application of a 5% acyclovir ointment for two to six months.

All 47 sarcoids responded to treatment, with complete regression of 32 tumors. The remaining lesions showed only partial regression, most likely because of their thickness.

The researchers propose that acyclovir can be used routinely for mild sarcoids as an adjunct to surgery.