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This information is provided by Provet for educational purposes only.

You should seek the advice of your veterinarian if your pet is ill as only he or she can correctly advise on the diagnosis and recommend the treatment that is most appropriate for your pet.

Urinary incontinence due to sphincter mechanism incompetence is common in adult female dogs, and uncommon in males

Many female dogs (especially large and giant breeds) develop sphincter mechanism incompetence. Urine leakage usually occurs when the animal is relaxed and lying down. 

Contrast radiography reveals that the urethra is very short in many of these bitches, and the bladder lies well within the pelvic canal. There is an increased risk of this disorder developing in :

  • Bitches that have been spayed
  • The following breeds : Doberman Pinschers; Irish Setter; Old English Sheepdogs; Rottweilers; Springer Spaniels; and Weimaraners.

Because the underlying cause is still not fully understood and there are several possible mechanisms involved, treatment that is successful in some cases does not always work for others.

Treatments that may be used include :

  • Colposuspension - this technique, which involves fixing the bladder neck within the abdomen by stitching the vaginal walls to the prepubic tendon on either side,  is preferred by many veterinary urologists as it results in about a 50% success rate when performed by an experienced surgeon.
  • Surgery to increase urethral resistance or increase urethral length - not recommended
  • Therapeutic drugs
    • Phenylpropanolamine (a sympathomimetic, alpha-adrenergic drug) - 1.5mg/kg body weight twice daily.
    • Oestrogens - with or without phenylpropanolamine

Sphincter mechanism incompetence is much less common in male dogs but when it does occur medical treatment is used more often than surgery (and androgens may be tried), though the success rate of all forms of treatment is lower than in females.


Updated October 2013