Despite her best efforts, your house-trained dog may sometimes leak a bit of urine here and there. You may call those leaks "accidents," but when a dog can't control passing urine, she has incontinence. If your dog takes steroids, they may be indirectly causing her lack of control.
About Incontinence
According to Washington State University's School of Veterinary Medicine website, urinary incontinence is the "involuntary passing of urine." Different from frequent urination, incontinence can present for a variety of reasons, including issues with the urethra and bladder, and irregularities in the communication between the areas of the brain and spinal cord responsible for bladder control.
Effect of Steroids on Incontinence
A dog's adrenal cortex naturally produces cortisol, a hormone with anti-inflammatory properties and helpful in dealing with stress. Synthetic hormones, such as prednisone and trimacinolone, are used to treat a variety of diseases in dogs. Though steroids are effective, they also have potential short-term side effects including increased thirst, potentially leading to incontinence if the dog doesn't have easy access to a break spot. Using steroids for longer than four months may result in long-term side effects including latent urinary tract infections, also a cause of incontinence.
Other Causes of Incontinence
Older dogs often experience incontinence as the muscles responsible for holding urine in the bladder weaken. Hormone-responsive incontinence may occur in spayed and neutered dogs, causing them to leak urine while they rest; older dogs may simply become senile and unaware that they're dribbling urine. When incontinence is caused by hormone reactions or loss of muscle control, medication is often effective for controlling leaking urine.
Estrogen to Help
The synthetic estrogen known as diethylstilbestrol is commonly prescribed to tone a dog's bladder muscles. Though estrogen is a hormone, diethylstilbestrol is a nonsteroidal hormone, so it doesn't present the side effects that steroids risk. High doses of diethylstilbestrol carry the risk of bone marrow suppression, though. Other medications, such as phenylpropanolamine, pseudoephedrine and ephedrine, target the bladder sphincter's receptors as a signal to hold urine.