00726-A: Pharmacokinetics of Topically Applied Ciprofloxacin in Canine Tears

Grant Amount: $5,265.81

Diane Hendrix, DVM; University of Tennessee

April 1, 2006 - March 31, 2007

Sponsor(s): Australian Terrier Club of America, Bichon Frise Club of America, Inc., Samoyed Club of America Education & Research Foundation, San Joaquin Kennel Club

Breed(s): -All Dogs

Research Program Area: Ophthalmology

Abstract

Ulcerative keratitis (corneal ulceration) occurs very commonly in dogs. Corneal ulcers usually occur secondary to trauma, but may also occur secondary to lack of tear production, eyelid abnormalities or nerve damage. While corneal ulcers occur in all breeds of dogs, brachycephalic breeds such as Pekingese, Lhasa Apsos and Shih Tzus, have a higher incidence of ulceration. Additionally, corneal ulcers in brachycephalic breeds are more likely to become infected than ulcers in mesocephalic or dolicocephalic breeds. The anatomy of brachycephalic dogs with prominent, frontally placed globes leads to corneal exposure. Often concurrent eyelid abnormalities, abnormally low tear production, and increased tear evaporation slow healing, increasing the chances of corneal invasion by bacteria. Infected corneal ulcers can develop rapid stromal dissolution leading to globe perforation and iris prolapse. When this occurs surgery is required to restore globe integrity, but even with prompt surgical intervention, blindness may still occur. Appropriate antibiotic usage is paramount in the prophylactic treatment of non-infected ulcers and for the treatment of infected ulcers where rapid killing of the bacteria helps prevent worsening of the ulcer. No studies have been done to evaluate the pharmacokinetics of ophthalmic antibiotics in the tear film of dogs. Studies in normal humans, rabbits, and horses have shown that ciprofloxacin maintains a concentration greater than the MIC for most bacteria longer than 4 hours. We would like to evaluate the pharmacokinetics in the tear film of normal mesocephalic and brachycephalic dogs.

Publication(s)

None at this time.