No butts about it, anal gland issues are not at the top of anyone’s conversation list. However, it is a fairly common problem that occurs in many of our pets.
Anal sac impaction most often results in only minor irritation (or, shall we say, “rear-itation”), but if left unchecked, an anal sac abscess can develop. This is a common complication that I see in the ER. Owners usually present their pet for “bleeding from the rectum,” when in reality, it is a ruptured anal sac that is draining blood-tinged fluid. It’s what I refer to as “anal sacs gone bad.”
What are they?
Anal sacs are two grape-sized glands just inside of your pet’s anus that contain a foul-smelling material. Prior to domestication, these glands served the purpose of marking an animal’s territory, and could be readily emptied voluntarily. Pets nowadays have largely lost their ability to empty their sacs on demand, and the process occurs naturally during normal defecation when firm feces are passed, lubricating the anal opening in the process. Glands can also “spontaneously empty” during times of stress or excitement; you can recognize this has happened if your dog suddenly develops a very unpleasant odor.
What is the anatomy?
The drawing (below, left) shows the location of normal-appearing anal glands in the dog. The glands lie beneath the surface of this skin and are not something that you can visibly see. The second image (below, right) shows both an inflamed anal gland as well as a ruptured anal gland (more on this below).
How does it happen?
Anal sacs become impacted when a blockage develops in the duct that leads from the gland to the anus. Main causes for the development of a blockage in the duct include having a softer stool or diarrhea, allergies that result in inflammation of the sac and duct, or just plain luck of the genetic draw. Surprisingly, worms are NOT a general cause. (It is a common misconception that a “dog scooting” means that your dog has worms.)
At this stage, the gland is generally swollen and not painful. However, if an infection develops the area can then become painful, swollen and sometimes result in the formation of an abscess. Infection develops because blockage of the duct results in inflammation of those local tissues. In general, when any tissue is inflamed it is no longer happy and healthy, making it easy for the bacteria that normally live in the area to get out of check and “take over,” causing an infection.
How can I tell if my pet’s anal sacs are causing a problem?
One of the first things owners often report is a “scooting” behavior; they observe their pets dragging their bottoms along the floor or carpeting in an attempt to empty the glands. Some dogs will also lick the anal area while others will nip and bite at their bottom or chase their tails.
How is it treated?
I bravely tackled the mission of watching a disturbing array of YouTube videos, trying to find one that best demonstrated the task properly. This video  provides a good illustration of the task. It may be considered graphic by some, so please don’t click the link if you are easily queasy—some things are best left to professionals.
Can I express my pet’s anal glands at home?
Obviously, this is not for everyone, but if you feel comfortable doing so, this is a procedure that can be done at home. It is strongly recommended that you have your veterinarian or groomer demonstrate how to do this for you, for your first time. A second pair of hands up at the front of your dog or cat is helpful to give distracting rubs on the head and praise. A word of caution: Expressing incorrectly can cause irritation and lead to further problems so make sure you are able to perform the task correctly.
What if the scooting continues?
Your veterinarian should recheck the glands if the scooting behavior continues more than a couple of days following sac emptying. If left unattended, an abscess can develop in the gland and rupture through the skin of the rectal region. A ruptured anal sac abscess is oftentimes mistaken for rectal bleeding. Anal sac abscesses are generally treated with antibiotics, pain medications and warm compressing the area at home.
Another important reason to have your pet examined by your veterinarian if scooting continues is that there could also be other causes of this behavior such as allergies, parasites or even referred back pain.
What if my pet suffers from anal sac impaction on a regular basis?
If your pet’s anal sacs need to be emptied every month or more, you may opt to have the sacs surgically (and therefore permanently) removed. The procedure can be complicated as the sacs are located next to many important nerves—mainly those that control rectal sphincter function—and meaning, if improperly performed, your pet could permanently loose control of its bowel function. Despite how scary this sounds, anal sac removal is considered a relatively “simple” surgery by experienced surgeons.
While not the most pleasant of topics to cover, I hope you have found this information informative and helpful!