Hormone-induced urinary incontinence. Hands down, the most common reason for involuntary urine leakage in dogs is hormone-induced urinary incontinence. After a dog is spayed or neutered, the sex hormones estrogen and testosterone, which are necessary to help close the external urethral sphincter, are no longer available. This often results in urine dribbling.

Hormone-induced urinary incontinence is extremely common in spayed female dogs, and somewhat less common in neutered males. These are typically healthy, vibrant pets that just happen to dribble urine anywhere from multiple times a day to just once or twice a year.

Age-related urinary incontinence. Older pets can develop weak pelvic floors or poor bladder tone that can result in urine dribbling. If your dog has signs of canine senility or dementia, he can also simply forget to signal you when he needs to potty outside. His bladder can overfill, and there can be leakage.

Damage to the pudendal nerve. This is a problem of the lower back in dogs, often in older dogs with arthritis, degenerative myelopathy or joint disease, or trauma to the lower back. If the pudendal nerve, which works the neck of your petís bladder, is impinged, the bladder neck can remain slightly open, allowing urine leakage.

Birth defects. Birth defects ó structural abnormalities existing from birth ó can cause incontinence. If your puppy has been difficult or impossible to housetrain, there could be a birth defect present. An example: the ureter ó a tube that collects urine from the kidneys and passes it into the bladder ó can bypass the bladder entirely and go directly to the urethra.

This plumbing problem, known as an ectopic ureter, will cause urine, as itís produced, to dribble right out of your petís body. Some dog breeds have more of these types of from-birth plumbing problems than others, including Siberian Huskies, Miniature Poodles, Labrador Retrievers, Collies, Westies, Wirehaired Fox Terriers and Corgis. If your puppy is leaking urine, you should investigate the possibility of a birth defect.

Bladder stones. A dog with a bladder stone will often strain while trying to urinate. Heíll appear to successfully empty his bladder, but when heís back inside heíll continue to leak urine. If youíve noticed this behavior with your pet, you need to consider the possibility of bladder stones.

Urethral obstruction. Obstruction of the urethra can also cause involuntary passage of urine. A tumor, for example, can obstruct urine flow and cause dribbling. So can urethral stones.

A stone in your petís urethra is a medical emergency. You may notice along with urine leakage that your pet is in pain, seems stressed and might even act panicked. This can be because she needs to empty her bladder and canít. The bladder is filling up with urine and thereís no way for her to relieve the mounting pressure.

You should seek veterinary care immediately if your pet seems to have pain along with incontinence, and especially if heís not able to pass any urine at all.

Disease of the bladder, kidneys or adrenals, Cushingís disease, hypothyroidism and diabetes can all cause dribbling of urine.

Central nervous system (CNS) trauma. If your petís brain or spinal cord isnít signaling correctly to the bladder, this miscommunication can cause urine dribbling.