Introduction

Conjunctivitis (“red eye”) refers to inflammation of the delicate, well-vascularized membrane lining the eyelids and covering parts of the eyeball (called the “conjunctiva”). There are many causes of conjunctivitis, including trauma, allergies, foreign body intrusion and bacterial or viral infection. Treating conjunctivitis requires extensive testing to determine its underlying cause. Of course, any treatment protocol must be tailored to the cause of conjunctivitis in that particular dog.

Treating Conjunctivitis

The goals of treating conjunctivitis are to resolve the underlying cause, eliminate any bacterial, viral or fungal infection and eliminate ocular pain associated with the condition. A thorough ophthalmic examination must be done, including assessment of all conjunctival surfaces, taking samples for bacterial and fungal cultures, examination of conjunctival cells microscopically for infection or other disorder, applying fluorescein dye to examine internal eye structures, assessing tear production via a Schirmer tear test and testing intraocular pressure.

In most cases, topical, broad-spectrum antibiotics in the form of prescription eye drops will resolve conjunctivitis caused by bacterial infection in dogs. These drops also sooth and wash over the eyes, promoting healing. Topical steroid eye drops may be added to the protocol to reduce inflammation.

If eye drops are not effective and a more chronic condition develops, further investigation into the cause of the condition is necessary. Normally, this will include referral to a specialized veterinary ophthalmologist for advanced diagnostic testing. These tests will check for foreign objects or parasites which may be contributing to eye irritation. The veterinarian will examine and sample cells of the irritated eye tissue to determine whether any viral components or resistant bacteria are involved. If a foreign object or parasitic infection is found, surgical removal may be necessary. If a virus is detected, anti-viral eye drops may be prescribed. If an especially resistant bacteria is suspected, samples will be cultured to determine which particular antibiotic, or combination of antibiotics, will effectively eliminate the infection. Dogs experiencing chronic conjunctivitis due to seasonal allergies can be given prescription eye drops, especially during the seasons in which the condition is worse. A number of oral medications are available as well, particularly if the eye redness is secondary to some other underlying condition.

While chronic conjunctivitis can be frustrating for owners, it usually can be treated effectively once the cause is determined. In most cases, it is best to consult with a veterinarian who has advanced training in ophthalmology in order to resolve chronic eye conditions.