Q. I have a 9-year-old 46-pound Fox Terrier/Lab mix. She has been urinating in her kennel (which is never locked) and on her blanket. This has never happened before. What do you think could be wrong? She is extremely mortified when she has an accident.
A. Urinary accidents in middle-aged, spayed, female dogs are almost always one of two things, so perhaps we can sort it out. If your dog appears to be urinating small amounts frequently and seems agitated or uncomfortable, she may very well have a urinary tract infection. This is fairly common in older females. The only way to be sure is to have your veterinarian examine her and run a test on a sample of her urine.
The second and most probable explanation is that your dog has developed estrogen-related urinary incontinence. As spayed females get older, their estrogen levels drop, and this can decrease their muscle tone in their urethral sphincter, a ring of muscle that controls urination. An owner will notice random accidents, without evidence of straining or discomfort. Urinalysis will be normal. Sometimes, dogs will even urinate while they are sleeping, and you will find a puddle of urine when they awake.
The treatment for both conditions requires a veterinary exam and prescription. For a urinary tract infection, antibiotics usually clear up the problem, while urinary incontinence usually responds to phenylpropanolamine, a medication that improves muscle sphincter tone and control.
Rarely, abnormal urination could be the result of something more unusual such as a bladder tumor or bladder stones. Usually there is significant discomfort, possibly blood in the urine, and sometimes other signs such as weight loss that suggest a more serious problem.
Most likely this is a straightforward problem that can be solved with a visit to your vet and a simple lab test. By the way, the best way to collect urine from a female dog is to follow her outside with a soup ladle, and catch some urine when she squats.
Make sure to refrigerate the sample until you can take it to your veterinarian, and by all means label it. Your housemates and family will appreciate it!