|Veterinarians use a small piece of absorbent material called a 'Schirmer tear test strip' to help in measuring tear production. This small strip is placed inside the lower eyelid. Over a measured period of time, usually one minute, the tears soak and migrate up the strip, causing a change in color. The wet area of the strip is then measured and compared to normal values. In the photograph below, a normal result is shown on the left, and an abnormal reduction in tears is shown on the right.
Abnormal tear production with the associated signs of a red eye with a lot of discharge can occur in several diseases. One of them is called keratoconjunctivitis sicca (KCS), or 'dry eye,' in dogs.