“Is your cat drinking more or urinating more?” This is one of the most common questions asked by veterinarians to clients about their feline pets. If your answer is “yes” the next step is a thorough exam and routine blood work with a urinalysis on your cat. These tests will help your veterinarian determine why your kitty is drinking and urinating more.
Excessive urination (polyuria) goes hand in hand with excessive drinking (polydipsia). Normal water consumption for your cat should not exceed 20mg/lb/day. For example, a normal 10 pound cat should not drink more than 200 ml of water. This is about one measuring cup of water.
There are many causes of increased drinking and increased urination in cats. Three of the most common causes veterinarians see in middle age to older cats are hyperthyroidism, diabetes mellitus, and kidney failure.
Hyperthyroidism is the most common endocrine (hormone) disease in cats. It is a disease caused by a functional tumor of the thyroid gland resulting in an excess of thyroid hormone. The most common clinical signs of a cat with hyperthyroidism are increased appetite, weight loss, increased thirst and increased urination. Treatment includes a specialized diet, medication, radioactive iodine treatment or surgery.
Diabetes mellitus is the second most common endocrine disease in cats, affecting an estimated one in four hundred cats; it is seen more frequently in middle to old-age, overweight, cats. Diabetes mellitus is a disease process that relates to the inability of the body to make insulin or respond to insulin that is produced by the pancreas. If insulin is not available or the body does not respond normally to insulin then the level of blood glucose will remain high in the blood. When the glucose gets to above a certain level in the blood then it will pass through the kidneys (at normal glucose levels this should not happen). Glucose is a very large molecule and when it passes through the kidneys it drags water with it due to osmosis. The end result is a cat that is peeing more and therefore needs to drink more! The most common clinical sign seen in diabetic cats is an increase in water consumption and urination. Other clinical signs include weight loss, increased hunger, weakness and urinary tract infections. Diabetes is treated with diet and insulin therapy.
Kidney failure is a very common disease in older cats. These cats lose both the ability to filter out toxins in the body and to concentrate urine and maintain hydration. As a result they accumulate toxins in the blood stream that can make them feel ill. These cats need to drink more water to replace what they lose in excess urine production. Treatment includes medications and special diets that may be used to slow the disease progression and keep cats with kidney failure feeling better for longer. Fluids (given either under the skin or intravenously) can help supplement fluid intake when the cat is no longer able to drink enough water to keep himself hydrated.
If you think your cat may be drinking or urinating more that normal please contact your veterinarian for a consult. Many disease processes if caught early can be controlled and treated to allow your kitty a longer, healthier 9 lives!