Urinary incontinence is the involuntary passing of urine. Pets can be incontinent for many different reasons. Those reasons can involve the bladder, the urethra which is the tube from the bladder to the outside, or incontinence can be caused by abnormalities in the parts of the brain and spinal cord that control bladder function. Incontinence can be confused with diseases that cause a pet to urinate frequently. A physical exam and laboratory tests will help in the proper diagnosis.
More than 20% of spayed females are affected with urinary incontinence. Both male and female dogs can be affected, with medium to large breeds being more prone for the problem. The number of cases is likely to increase with the growing number of older dogs, advances in geriatric veterinary care and significant amount of time pets spend indoors. Urethral Sphincter Mechanism Incompetence is the most commonly diagnosed cause of urinary incontinence: 81% of incontinent adult females and 57% of all dogs with involuntary urine loss. Phenylpropanolamine is the most frequently dispensed medication for this type of incontinence.
A bladder infection can cause either a strong urge to urinate or if the bladder infection is long standing it can cause scarring of the bladder preventing it from stretching to hold urine. In this case the pet is usually not truly incontinent in that they know they are urinating, but they have such a strong urge to empty their bladder that they may urinate in abnormal locations or urinate very frequently.
Hormone-responsive incontinence occurs in neutered dogs of both sexes but occurs most commonly in female dogs. The pet can urinate normally, but they leak urine while resting. Hormone-responsive incontinence can occur months to years after a pet is neutered. As pets age they may become incontinent. This may be due to a weakening of the muscles that hold urine in the bladder. There are also diseases that can cause a pet to create more urine than normal and several of these occur in older pets. Older pets can also develop senility and simply be unaware that they are dribbling urine.
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