Chronic stress, or a constant stress experienced over a prolonged period of time, can contribute to long-term problems for heart and blood vessels. The consistent and ongoing increase in heart rate, and the elevated levels of stress hormones and of blood pressure, can take a toll on the body.
Excess Tearing. The most common cause of tear stains in dogs is excess tearing or epiphora, which makes the hair and skin around the eyes damp. This can lead to the growth of bacteria and yeast. Red yeast, which produces a reddish brown discoloration of the face, is a common cause of tear stain problems.
Dry eyes are caused by a lack of adequate tears. Your tears are a complex mixture of water, fatty oils and mucus. This mixture helps make the surface of your eyes smooth and clear, and it helps protect your eyes from infection. For some people, the cause of dry eyes is decreased tear production. For others it's increased tear evaporation and an imbalance in the makeup of your tears. Decreased tear production.