Anal Sac Disease

What is their function?

The secretion acts as a territorial marker – a dog’s ‘calling card’. The sacs are present in both male and female dogs, and are normally emptied when the dog defecates. This is why dogs are so interested in smelling one another’s feces.


Why are the anal sacs causing a problem in my dog?

Anal gland anatomy

Anal gland anatomy

Anal sac disease is very common in dogs. The sacs frequently become impacted, usually due to blockage of the ducts. The secretion within the impacted sacs will thicken and the sacs will become swollen and distended. It is then painful for your dog to pass feces. The secreted material within the anal sacs forms an ideal medium for bacterial growth, allowing abscesses to form. Pain increases and sometimes a red, hot swelling will appear on one or both sides of the anus at the site of abscessation. If the abscess bursts, it will release a quantity of greenish yellow or bloody pus. If left untreated, the infection can quickly spread and cause severe damage to the anus and rectum.


How will I know if my dog has anal sac problems?

The first sign is often scooting or dragging the rear along the ground. There may be excessive licking or biting, often at the root of the tail rather than the anal area. Anal sac impaction and infection is very painful. Even normally gentle dogs may snap or growl if you touch the tail or anus when they have anal sac disease. If the anal sac ruptures, you may see blood or pus draining from the rectum.


What should I do?

Problems with the anal gland are common in all dogs, regardless of size or breed. If you are concerned that your pet may have an anal sac problem, call your veterinarian at once.  Treatment for impaction involves flushing and removal of the solidified material. Since this condition is painful, many pets will require a sedative or an anesthetic for this treatment. Antibiotics are often prescribed and sometimes may need to be instilled into the sacs over a period of several days. Most dogs will receive pain relief medications for several days until the swelling and pain have subsided. In advanced cases, surgery may be necessary.


Is the condition likely to recur?

Many dogs w ill have recurrent anal sac impactions or abscesses.  Recurrence often results in scarring and narrowing of the ducts, leading to even more frequent recurrences.  If this condition recurs frequently, surgical removal of the sacs is indicated.


Are anal glands necessary for my dog?  Will removal have any adverse effects?  Will my pet miss them?

Anal glands produce the pungent smelling secretion that allows the dog to define his or her territory. For our domesticated dogs, this is unnecessary and will not adversely affect your pet.


Are there any other risks attached to surgery?

This is a delicate and specialized surgery. Many veterinarians perform this procedure routinely; however, in severe cases, your veterinarian may recommend referral to a board-certified veterinary surgeon. The main complication of surgery is permanent damage to the nerves that close the anal sphincter. Although this complication is rare, it can result in fecal incontinence or the inability to control bowel movements.

Some dogs will experience loose stools or lack of bowel control for one to three weeks following surgery, which resolves without further treatment in the majority of pets.

As with any surgery, there are other risks and potential complications. Continued advances in anesthesia have lead to fewer risks. . For dogs suffering from chronic or recurrent anal sac infection or impaction, surgical removal is the best option to relieve the pet’s pain.


My dog is very nervous and sometimes seems to express his own glands. Is this normal?

It is common for dogs to express their anal sacs, particularly if frightened. Some dogs even appear to lack control of the anus or anal sac ducts so that small quantities of fluid will drain out when they are resting. This, of course, leaves an unpleasant lingering odor in the home. For dogs with this condition, surgery may be recommended.



  This client information sheet is based on material written by Ernest Ward, DVM.

© Copyright 2005 Lifelearn Inc. Used with permission under license. April 21, 2014