Bladder spasms in dogs usually indicate a bladder infection. Infections irritate the bladder wall, causing its muscles to spasm. This in turn leads to an urge to urinate more often than usual or necessary. Often, this leads to frequent urination attempts with straining and very little production of urine released. Sometimes the small amount of urine is cloudy or bloody. This signals a visit to the veterinarian for diagnosis and treatment.
Bladder Stores Urine
The bladder is a sac-like organ located within the abdomen between the rear legs. After the blood is filtered by the kidneys, any liquid waste material is directed into the bladder for temporary storage. When the bladder is almost filled, the bladder muscles contract, sending the urine through the urethra and outside the body. The ring-like sphincter muscle surrounding the urethra near the bladder constricts, trapping the urine inside the bladder. When this sphincter muscle relaxes, the urethra is opened and this allows the urine to flow outside of the body.
Bladder Infection
Normally urine is bacteria-free; however, bacteria can enter the bladder through the urethra. These bacteria can cause inflammation, pain, crystals or stones inside of the bladder. Stones can obstruct the flow of urine, which is toxic, and can cause several health problems. Ultrasound and/or x-rays will confirm the presence any bladder stones. Stones can be dissolved by feeding the dog a special diet. They can also be treated with sonic vibrations that break stones apart and into smaller pieces that can pass through the urethra, or by surgery.
Muscle Spasms
Bacteria inside of the bladder will cause irritation. This leads to spasms of the bladder wall muscles. This in turn causes the dog to attempt to urinate even if he does not have to relieve himself. This straining attempt to urinate can cause cloudy or bloody urine to be expelled. This can be exhausting and frustrating for the dog as well as the owner.
Since there is no medication to treat the bladder muscle wall spasms, the treatment targets the cause of the spasms, i.e., the bladder infection itself. Urinary infections are the most common cause of incontinence. This is especially true for female dogs of all ages. The female urinary tract is more susceptible to infection since the length of the urethra is shorter.
A urine culture will determine the type of bladder infection and what types of antibiotics are available for the treatment. Different antibiotics fight different types of bacteria. Determining factors in the selection of an antibiotic include: rate of success against the particular bacteria, expense, ease of use and potential side effects. After one to three weeks of treatment, a second culture is taken to determine the success or failure of the antibiotic being used. Then the antibiotic is continued or a new one is tried. Usually shortly after treatment starts, the incontinence improves and the bladder wall muscle spasms cease.
The antibiotic must be continued until the veterinarian determines that the infection has been cured. If the antibiotic is discontinued too early, the infection can return and can actually be worse than the previous bout. In addition, the bacteria can become a "super bacteria," meaning that the bacteria are now immune to the antibiotic.