Dyschezia (Painful Defecation) in Dogs

Dyschezia is the medical term used to describe painful or difficult defecation. There are a variety of causes of dyschezia. Some pets have temporary dyschezia but in others, difficult defecation may represent a more severe illness. For this reason, dyschezia should not be ignored and should be addressed if it persists or worsens.

Painful defecation usually arises with some disorder of the colon or rectum. It can also occur when there is some physical impediment to defecation in the area of anus or perineum (area around the anus under the tail). Because the colon and rectum pass through the canal formed by the pelvic bones, fractures, dislocations and diseases of the pelvis may also result in dyschezia. The colon also passes immediately over the prostate gland in the male dog, so diseases of the prostate may secondarily cause painful defecation.

Causes

• Constipation or obstipation (severe constipation)
• Colitis or proctitis (inflammation of the colon/rectum)
• Masses within the colon or rectum and at the anus or perianal area, such as cancers or polyps
• Foreign bodies within the colon or rectum
• Strictures (narrowing) of the colon, rectum or anus
• Deviation or sacculation (dilation of a portion) of the rectum
• Anal sac infection, abscessation, or cancer
• Perineal hernia, which is herniation of tissue from within the pelvis into the soft tissues behind the hip
• Perianal fistula (ulcerated, infected tracts that lead from the rectum to the skin around the anus)
• Pseudocoprostasis where hair around the anus becomes matted with feces
• Masses, fractures, injuries or infections of the pelvic bones
• Disorders of the prostate, such as infection, abscessation, and cancer

What to Watch For

• Distress and vocalization during defecation
• Excessive straining associated with defecation
• Reluctance to defecate
• Fresh blood in the stool
• Weight loss
• Poor appetite
• Diarrhea

Diagnosis

• Thorough history and physical examination, with a digital rectal palpation and close examination of the anus and perineum
• Complete blood count (CBC)
• Biochemical profile
• Urinalysis
• Fecal examination
• Abdominal and pelvic radiographs (X-rays)
• Possibly abdominal ultrasonography
• Colonoscopy or proctoscopy – examination of the colon and rectum with either a rigid or flexible scope

Treatment

There are several things your veterinarian might prescribe to treat your pet symptomatically; however, depending on the underlying cause of dyschezia, a more specific therapy would be recommended.

• Clipping the hair and washing the perineal area may be of benefit in some cases of perineal and rectal disorders.
• Enemas, fluid therapy, and/or stool softeners may be used to treat constipation and obstipation. Relief of obstipation may require general anesthesia and the administration of high enemas.
• Stool softeners may also be helpful in the management of rectal sacculations, hernias, certain prostate diseases, strictures, and during the healing of pelvic fractures.
• Dietary management (such as increasing the fiber in the food) may be of benefit in certain cases of colonic disease, particularly colitis and proctitis.
• Antibiotic therapy is administered for anal sac infections and abscesses, and for certain colonic and prostatic disorders.
• Surgical intervention may be necessary in disorders such as perineal hernias, certain pelvic fractures, tumors, foreign bodies, and strictures.
• A variety of treatments that involve both medications and surgery are available for perianal fistulas.

Home Care

Administer any prescribed medications as directed by your veterinarian. Follow dietary recommendations and observe your pet's general activity and appetite. Watch closely for the presence of blood in the stool or a worsening of signs. If pseudocoprostatis was the source of the dyschezia, then continue to cut or clip the hair from away from the anal area.