By DR. FRED SELF / Veterinarian

Everybody has heard the question, “Which came first — the chicken or the egg?”

In veterinary medicine, we deal more with the question, “Which came first — the excessive water drinking or the out-of-control urinating?”

Polyuria and polydipsia, sometimes called PU/PD, is a condition that produces an abnormally high desire for water and an abnormally large urinary output. Every time you turn around, your pet needs to go outside.

There are several conditions that can cause PU/PD. Some of these conditions may be mild, like too many salty treats or an uncomplicated urinary tract infection. However, there are several common conditions that require quick attention.

Diabetes mellitus, often just called diabetes, is a common condition in both dogs and cats. Because the body does not use sugars properly, they build up in the blood stream. This build-up of sugars causes the body to think it needs to drink water in order to dilute the blood. The resulting increase in water intake causes an increase in urinary output.

Kidney disease appears in middle-to-older-aged pets. It is the kidneys’ job to flush the body of toxins and maintain the body’s fluid level. A diseased kidney, however, flushes the body’s fluid and maintains the toxins. In addition to feeling sick, a pet with kidney disease has an increased urinary output that causes it to drink more water in order to maintain a proper fluid level.

Cushing’s disease is a condition caused by abnormal adrenal gland activity. The adrenal glands help produce steroids for the body. With Cushing’s disease, the adrenal glands overproduce the steroids. Just like in the case of taking Prednisone, a type of steroid, the body responds by increasing water intake and urinary output.

Without doing some diagnostic work on a pet with PU/PD, there is no way to know which condition is the cause. Any pet with PU/PD should have blood work and a urinalysis performed.

In many cases this basic diagnostic process can reveal the cause. For most causes of PU/PD, there is some form of therapy. The therapy may not cure the condition but should help to lessen the amount of water intake and urinary output.

If you think your pet is drinking more than normal, try to measure its water intake over a 24-hour period, and then call your veterinarian to set up an appointment.

Dr. Fred Self is a veterinarian at Shelbiana Animal Clinic in Columbiana, along with Dr. Charles Thornburg. You can reach them at 669-7717.