Anal Sacs (Glands)

Reviewed by Paula Hendricks 12/17/16

Anal Sacs are small paired pockets located between the internal and external anal sphincter muscles, one on each side of the anus at the 4 and 8 o’clock position. The sac empties through a short and narrow duct to the surface near the inside edge of the anus. Each sac is lined with abundant sebaceous (oil) glands and numerous apocrine (sweat) glands. The secreted substance is a semi-oily, brownish fluid that packs a very unpleasant odor. Problems with the anal sacs are more common in smaller breeds of dogs than in the larger breeds.

If you notice your dog scooting on the rug or across the floor, licking or biting their rear end, a strong unpleasant odor or constipation/pain when pooping/sitting, chances are the dog may have anal sac disease.  Normally, when a dog poops the fluid in the anal sacs is squeezed out, also.  Problems can arise when the anal sacs are not completely emptied.  If that occurs, the fluid then becomes dry and thick, plugging the openings.  This is called impaction.  Left untreated, anal impactions can become infected.

Impacted anal sacs are easy to treat.  The glands can be gently emptied, or expessed with your fingers.  Your vet can show you how to express anal glands or you can watch this video: How to Express Your Dog’s Anal Glands You TubeYour vet can advise on if this is necessary and if so, how often it should be done.  If your dog has repeated problems, your vet may want to remove his anal sacs with surgery.

Putting your dog on a healthy diet, keeping it at a healthy weight and making sure it gets plenty of exercise may help avoid anal sac disease.

Research for this article includes:

The Merck Veterinary Manual

The 5 Minute Veterinary Consult by Larry Tilley & Francis Smith

Textvbook of Medical Physiology by Aurthur Buyton & John E. Hall

The Dog Owner’s Home Veterinary Handbook by James Griffen & Lisa Carlson