Anal Sac Disease

Anal Sac Disease

by Dr. Paul Newman

The anal sacs are located on either side of the anus, under the skin and sphincter muscle. They connect to the anus by means of small canals, or ducts. Anal sacs produce and store a dark, foul smelling fluid. These are the same type of sacs/glands that a skunk has, but their purpose in the dog or cat is questionable and may be related to territorial marking.

Normal emptying of the sacs are caused by the pressure a bowel movement and the contractions of the anal sphincter muscle. If, for whatever reason, this natural emptying does not occur the glands become distended with secretion. Discomfort or infection may follow.

Picture Showing Location of Anal Sacs

Diseases of the sacs/glands include:

  • Impaction – normal secretions are thick and cannot escape.
  • Infection – bacteria produce yellow or bloody pus. Other parts of the body may also be infected.
  •  Abscessation – as a result of infection, hot, tender, or red swelling forms near the anus and may burst and drain bloody pus.

Symptoms of anal sac disease are:

  • Scooting or dragging the anal area.
  • Excessive licking under the tail.
  • Soreness near the tail or anus.
  • Swollen area near anus.
  • Bloody or sticky drainage under the tail.

Treatment may include one or more of the following:

  • Massage to empty the sacs.
  • Antibiotic medication.
  • Instilling medication into the sacs.
  • Surgical drainage (lancing).
  • Surgical removal of the sacs and glands.

Obesity (overweight) and poor diet can be predisposing factors to anal sac disease.

A good weight control program and a high fiber diet will minimize this type of problem.