What are tear stains in dogs?
Tear stains in dogs are a common problem, visible as reddish-brown marks around the dog’s eyes, most easily seen on dogs with white or light-coloured hair. They are usually the result of the dog producing too many tears or having an inability for the tears to drain away as normal.
Some dogs produce too much of a pigment-containing molecule that can be found in dog tears and cause the staining. When the dog’s body breaks down red blood cells, a naturally occurring molecule remains as a waste product. These molecules, known as porphyrins, contain iron, which is responsible for the red colouration, which gets darker when exposed to sunlight. Porphyrins are usually excreted via the digestive system but in dogs, they are also removed from the body in urine, saliva and tears. Darker coated dogs can also suffer from tear stains, but the marks are harder to see on the dark hair. It is a good idea to check your dog’s eyes regularly for any problems.
There are a number of potential reasons for dogs’ eyes to water excessively, some of which are serious medical conditions. For this reason, it is important for go to your vet so they can perform a check-up when the signs of dog tear stains are first noticed.