Addressing urinary incontinence in dogs

Owners should know that dogs that “leak” urine aren’t doing it on purpose, writes veterinarian Natalee Holt, and there may be an underlying anatomical abnormality or hormone imbalance causing the problem. Dr. Holt explains that ectopic ureters and estrogen insufficiency are two conditions that can lead to urinary incontinence. Both usually respond to treatment.

Canine bedwetting is usually a lack of urinary control

Published:         Monday, July 9, 2012   

Usually, I like to start an article with a personal anecdote about me or my pet. The topic of urinary incontinence makes me less inclined to do that.

Urinary incontinence is a lack of voluntary control of urination. What that means for you is that your dog leaves a puddle in the house. The important thing about urinary incontinence in dogs is that it is not intentional. They have no knowledge that they are urinating inappropriately; they just can’t help leaking urine. Usually, this occurs while they are sleeping, and they will leave puddles on the couch or the bed. Sometimes, a dog will drip urine while they are walking around. If you see your dog posture to urinate inside the house, that is not incontinence.

There are two major causes of incontinence. Puppies can be born with an inappropriately formed urinary system called ectopic ureters. In this case, the kidneys produce urine appropriately, but the tubes carrying the urine into the bladder attach to the urethra instead of the bladder. The urethra is the tube leading from the bladder out to the open world. There is a sphincter at the juncture of the bladder and urethra that acts like a rubber band and keeps urine in the bladder. If the ureters deposit urine past this mechanism, the puppy will not be able to store urine in the bladder, and the urine will leak.

Many puppies with this problem have ureters that exit into the bladder and the urethra. This puppy will be able to urinate normally, but may leak in between. Most puppies with ectopic ureters will present for being difficult to house break. Sometimes dogs are adults by the time they are diagnosed. While a history can help a veterinarian make an educated guess as to what the cause of a puppy’s incontinence is, usually further diagnostics are required to confirm. A camera can be placed in the urethra to look for where the ureters exit or a CT scan can be done to identify the path of the ureters from the kidneys to their end point. The abnormal ureters usually are corrected surgically. A newer technique uses a laser introduced through a camera as a non-invasive method.

The other major cause of incontinence in dogs is hormone responsive incontinence, also known as spay incontinence. This problem has been reported in 10 percent to 20 percent of spayed female dogs, although it can occur in male dogs as well. The sphincter (the rubber-band around the urethra) is controlled by several chemicals in the body. Estrogen controls the number of receptors available to receive these chemicals. When a dog is spayed, the estrogen level changes and the sphincter control can be altered. This usually develops within three years of the spay procedure, but occasionally, it will develop further out from the procedure.

This type of incontinence is treated primarily with medication. About 85 percent of dogs will respond to a daily medication that activates adrenaline receptors. Sometimes this medication can cause anxiety, high blood pressure and increased aggression. Supplementing estrogen once weekly can help about 65 percent of dogs and has fewer side effects. Some dogs require both to have control. Dogs with mild incontinence can benefit from supplementation of soy isoflavones, which are marketed for post-menopausal women.

While the majority of dogs can be treated with medication, a small number don’t respond to either or a combination. Therapies for these dogs get a little more creative. One recommended therapy is collagen injections into the urethra. The collagen bulks up the urethra and creates an artificial sphincter that can help them keep urine in the bladder. There is also a band that can be placed surgically around the urethra. The band is filled with fluid to help create an artificial sphincter mechanism. Finally, there is a surgical method that pulls the bladder forward to alter the physics of emptying. Dogs requiring these procedures usually require medication afterward.

If you have a bedwetting dog at home or a dog that leaks urine, it is important to realize your dog may have no control over this. Consult your veterinarian to see if your dog could be incontinent and to see what therapies are available.

Your Pet is published on the second Monday of each month. Dr. Natalee Holt holds a doctorate of veterinary medicine from the Kansas State College of Veterinary Medicine. She became board-certified in internal medicine in 2011. Holt loves all aspects of internal medicine, but has a special interest in gastrointestinal diseases and immune mediated diseases. She and her husband Jonathan share their home with Becca the dog, Jasmine the rabbit, and their three cats, Kitty, Clara and Appomattox. Holt is a board-certified internal medicine specialist who practices with the Animal Medical Center of New England, 168 Main Dunstable Road, Nashua.