Do Brown Stains on a Dog's Eyes Come From the Food?

The rusty stains under your dog's eyes make her look a little sad, but more importantly, they may signal a health problem. Her tears naturally contain a red-brown pigment called porphyrin. A variety of health issues, from food allergies to eye disease, can cause excessive tearing that builds up stains on her fur. You can determine the cause of chronic tearing and eventually reduce the reddish-brown stains that mar her pretty face.

Dyes, additives and preservatives in dog food don't cause your dog's tears to stain her face, according to The Complete Healthy Dog Handbook, but it's possible your pup is allergic to something in her food. A food allergy may cause chronic tearing, itchy skin or an upset stomach. Determining whether your pal has an allergy and then learning the cause will require the help of your vet. Ask about a special diet to limit common allergen ingredients such as pork, beef, chicken, soy, wheat and corn. Your vet might recommend a hydrolyzed protein diet that breaks down protein so your dog's immune system won't react, or she may suggest a diet based on a protein source your pooch has never eaten before, to see if the problem clears up.

Airborne and environmental allergens such as pollution, dust, grass and pollen can irritate your pal's sensitive eyes, causing them to water. If allergies plague your pup's eyes, tearing can create rusty marks below her eyes and along her nose. Tests can isolate the cause of your puppy's teary eyes. Once your vet determines the cause, try to eliminate things your dog is sensitive to from her environment. A weekly bath with a medicated shampoo can remove irritants from your dog's coat and ease her allergic reaction, according to the ASPCA.

Toy and short-faced breeds are particularly prone to excessive tearing, also known as epiphora. Toy-sized pups, such as poodles and Pekingese, may have inadequate space for tears to pool, causing them to overflow onto facial fur, according to the Dog Owner's Home Veterinary Handbook. Short-faced breeds, such as boxers and bulldogs, may have bulging eyes with misshapen tear ducts that divert tears onto the dog's nose. Blocked tear ducts, shallow eye sockets and eyelids that turn inward all can produce the excessive tearing that discolors the fur. Teething puppies are also prone to watery eyes.

Your canine friend's weepy eyes may be a sign of a more serious illness, an ear or eye infection, or degenerative eye diseases such as glaucoma, cataracts or Progressive Retinal Atrophy (PRA). If you suspect your pup's tears are due to a serious eye disorder, seek veterinary treatment immediately, as some breeds inherit eye problems that can cause eventual blindness.

Check your dog's eyes for irritants. Trim facial hair away from her eyes to reduce the potential for aggravation. Ask your vet about medical treatments or surgery to address blocked tear ducts, cataracts and some types of glaucoma. He may prescribe medication to control tearing, and can advise you on how to safely clean brown stains from your dog's face without hurting the eyes. Wiping your dog's face daily with warm water or hydrogen peroxide can prevent stain buildup.