Urinary Incontinence in Dogs: Not the Same as House Soiling
We have two female adopted dogs who were neutered at eight weeks and six weeks. The younger one has had incontinence since she was very young. After taking hormones for a year it cleared up, but it is occurring again. A different vet said the hormones were bad and that there is another treatment. Also, the other dog has begun having the same problem. Do you have an opinion about this, and what other treatments are available?
Hormone-responsive urinary incontinence occurs often among middle-aged and older spayed female dogs. The syndrome is rare but not unheard of in young spayed female dogs, and rarer still among males and unspayed females.
The precise cause is not known. However, it is believed that hormones produced by the ovaries (and hence not present in the bodies of dogs that have been spayed) help to promote the competence of the sphincter muscle that controls output from the bladder. Some vets have speculated that anatomical changes that occur after spaying also contribute to the condition.
Dogs with the condition leak or dribble urine without being aware of it. Leakage is most likely to occur when a dog is sleeping or resting, but can occur at any time. This form of incontinence should not be confused with house soiling, in which dogs deliberately urinate inappropriately due to behavioral or medical concerns.
The first step is to confirm the diagnosis. Urinary tract infections, diabetes, and neurological disorders also can cause incontinence and require different treatments. Your vet should perform blood and urine tests and a neurological exam to rule out these other possible causes.
Despite its name, the most common treatment for hormone-responsive urinary incontinence is not a hormone. It is a medication called PPA (phenylpropanolamine) that helps to increase the function of the sphincter. Side effects are not common, and usually are temporary. The most frequently seen are restlessness, gastrointestinal upset, and decreased appetite.
Old-school types (and some newfangled vets) often prescribe a different medication that is a hormone. DES (diethylstilbestrol) developed a bad reputation a decade or two ago because it was linked to serious side effects including potentially life-threatening blood cell shortages. Cheryl, it sounds like the hormone you've mentioned is DES.
Recently experts have begun to develop a consensus that DES is safe for use in the treatment of this syndrome at low doses. However, the drug's historically bad reputation means it isn't commonly used, and a lot of vets still have a knee-jerk negative reaction when they hear about its use.
I always recommend the minimum effective dose, regardless of the medication. Also, many dogs grow out of hormone-responsive incontinence or experience the problem only intermittently. It often isn't necessary to medicate affected dogs for life. If the problem resolves, medication should be stopped and then re-started only if necessary.
A recent paper in California Veterinarian (published by my former surgery professor, Clare Gregory) described a new surgical treatment in which a device is implanted around the urethra. The device can be filled with saline solution (using a port on the thigh) as needed to apply supplemental pressure. Although the procedure is not yet commonly available, it appears to offer a permanent solution.
Some diets claim to help with hormone-responsive urinary incontinence, although I have not seen any evidence. In fact, I would avoid any diet whose supporters make such a claim, since they're claiming in essence that the diet contains hormones.
Finally, I want to be clear: Anti-spay fanatics should not get the idea that this post (or the existence of hormone-responsive urinary incontinence) gives them ammunition for their agenda. This is a minor problem (frankly, it's usually more of a problem for owners than for affected dogs), which is not always permanent. Compared to issues such as pregnancy (with concomitant complications and inevitable overpopulation and euthanasia), uterine and ovarian cancer, pyometra, and breast cancer -- all of which can be prevented with appropriate spaying -- incontinence does not even register as a drop in the bucket of canine health problems.