Overview of Preputial Discharge in Dogs

Preputial discharge is any substance flowing from the prepuce, which is the fold of skin that covers the penis. Often, licking at the prepuce/penis accompanies the discharge, so we may use the terms interchangeably.

General Causes of Canine Preputial Discharge

Preputial discharge may consist of blood, urine, or pus. The normal dog should have no discharge, although a small amount of whitish yellow “smegma” can accumulate around the preputial opening and is not considered clinically significant.

There are many potential causes. These include:

• Disorders affecting the prepuce, including neoplasia (cancer), trauma, foreign body, or inflammation of the penis/prepuce (balanoposthitis).
• Disorders of the urethra, including neoplasia, trauma, or stones (calculi).
• Disorders of the urinary bladder including infection, calculi, inflammation, or neoplasia.
• Disorders of the prostate, including infection or inflammation of the prostate (prostatitis), neoplasia, enlargement (hyperplasia), cyst, or abscess.
• Bleeding disorders (coagulopathies), including decreased platelet count (thrombocytopenia) or ingestion of rat poison.
• Urinary incontinence (inability to hold urine) secondary to an ectopic (abnormally placed) ureter or improperly functioning sphincter (tissue that acts like a door, controlling the release of urine).

The presence of preputial discharge most often suggests an underlying problem, ranging from a mild, relatively benign disorder to a severe, even life-threatening disease (such as a coagulopathy).

What to Watch For

• Spotting
• Swelling or inflammation associated with the prepuce/penis
• Excessive licking
• Any discharge
• Lethargy
• Fever
• Lack of appetite

Diagnosis of Preputial Discharge in Dogs

• Baseline tests to include a complete blood count (CBC), biochemical profile, and urinalysis. Although results may be within normal limits, they may reveal overt infection and inflammation.
• A bacterial urine culture to rule out a urinary tract infection.
• A bacterial culture and cytology of the preputial discharge.
• A coagulation (clotting) profile to document a coagulopathy in cases of hemorrhagic discharge.
• Abdominal radiographs (X-rays) to evaluate the urogenital tract, including the prostate.
• Abdominal ultrasound to assess the prostate and urinary structures.

Treatment of Preputial Discharge in Dogs

Although specific therapy may be indicated once a definitive diagnosis is established, there are several things that can be done to treat the symptoms while awaiting test results.

• Remove or treat any obvious inciting or underlying cause, such as foreign body, tumor, or infection.
• Flush the prepuce daily with antiseptic solution.

Home Care

• Administer all prescribed medication as directed by your veterinarian.
• Observe your pet closely. If the clinical signs are not improving or are getting worse, contact your veterinarian at once.