Cyclosporin for Chronic Superficial Keratitis

Chronic irritation or inflammation in a canine’s eye causes melanin granule deposition into the corneal layer. The pigmentation spreading through the cornea and pupil hinders light entering the eye, which can affect your dog’s vision and potentially lead to blindness. While this condition can occur in all species, it has a higher propensity in German Shepherds, Border Collies, and Belgian Tervurens. It is imperative to perform a thorough examination to evaluate the underlying problem causing superficial keratitis.

Predisposing Factors:

• High altitudes
• Severe air pollution
• Increased exposure to ultraviolet light
• Abnormal blink reflexes
• Keratoconjunctivitis sicca (KCS), causing poor tear production/lubrication, which leads to chronic inflammation

Other causes like ulceration and glaucoma should be treated by alleviating infection and pressure, respectively. Cyclosporin and tacrolimus have been shown to reverse or at least slow corneal pigmentation caused by pannus or KCS. These medications must be given indefinitely to help with inflammation and increase tear production. With proper treatment, this disease can be managed but not cured. Pharmacy Solutions can compound both ophthalmic cyclosporin and tacrolimus to alleviate this condition.

The key distinction in pigmentary keratitis is determining the causation, as treating the underlying issue will alleviate the condition.

Dosing:

• Cyclosporin 1% or 2%: Instill 1-2 drop(s) into affected eye(s) every 12 hours
• Tacrolimus 0.02% or 0.03%: Instill 1 drop into affected eye(s) every 12 hours

Reference: Williams DL, Hoey AJ, Smitherman P. Comparison of topical cyclosporin and dexamethasone for the treatment of chronic superficial keratitis in dogs. Vet Rec. 1995 Dec 16;137(25):635-9. PMID: 8693674.