A common cream used by people to treat cold sores could soon bring relief to cats suffering from painful eye infections.
Researchers have discovered that a 1% penciclovir cream—sold as Fenlips—is safe and effective when used on cats’ eyes.
This finding offers hope for simpler, easier treatment of feline herpesvirus type 1 (FHV-1), one of the most common causes of eye disease in cats.
FHV-1 is a virus that can cause chronic eye infections, discomfort, and even vision problems in cats. Many cats carry the virus for life, and it often flares up during times of stress.
Traditional treatments, such as oral antiviral medications like famciclovir, can be hard for owners to give and may not work as well in cats because their bodies don’t absorb the medicine efficiently.
In the new study, scientists tested penciclovir cream—usually used by people for cold sores—on cats’ eyes to see if it could safely fight the virus.
The research was led by Dr. Oren Pe’er, along with Dr. Lionel Sebbag and Professor Ron Ofri from the Koret School of Veterinary Medicine at the Hebrew University of Jerusalem, in collaboration with Professor Sara Thomasy and her team from the University of California, Davis.
Their findings were published in Research in Veterinary Science.
The results were very promising. The cream was well tolerated, caused no irritation, and kept antiviral levels in the cats’ tears high enough to fight the virus for more than eight hours.
This means that applying the cream twice a day might be enough to control infection symptoms.
In addition to lab studies, a survey of cat owners who had used Fenlips showed that most cats responded well to the treatment. About 85% of owners noticed no side effects, and 80% said their cats’ eye condition improved or greatly improved.
Dr. Pe’er said the findings point to a simple, over-the-counter solution that could make treatment much easier for cat owners. “Twice-daily application could be enough to keep the virus in check. It’s a major step toward improving both animal welfare and treatment compliance,” he explained.
The researchers caution that more studies with larger groups of cats are still needed before penciclovir cream can be officially approved for eye use in veterinary medicine. Still, the early results give cat owners and veterinarians new hope for managing one of the most frustrating and common feline eye diseases.
