Anal Sac Disease in Dogs

Medically Reviewed by Vanesa Farmer, DVM on August 20, 2024
2 min read

If you’ve seen your dog scooting across the room on their bottom, it could be a sign of anal sac disease.

Dogs have two small pouches on either side of their anus. They make a smelly, oily, brown fluid that dogs use to identify each other and mark their territory. It’s why they often sniff each other’s behinds.

Anal sac disease begins as an uncomfortable impaction and can progress to an infection or abscess.

  • Scooting
  • Licking or biting their rear end
  • A bad smell
  • Constipation or pain when pooping/sitting

Normally, when a dog poops, the fluid in their anal sacs is squeezed out, too. It’s when they aren’t completely emptied that problems develop. The fluid inside can become so dry and thick that it plugs up the openings. This is called impaction.

There are two commonly done ways to empty or express anal glands. They can be emptied either externally or internally. Many dogs with truly impacted anal sacs need internal anal sac expression.

If your dog repeatedly has impactions, your vet may suggest adding more fiber to their diet. This increases the size of their poop, which puts more pressure on the sacs to empty naturally.

If your dog doesn't have a problem, there is no need for you to empty their sacs.

Left untreated, the impaction will turn into an infection. Look for yellow or bloody pus oozing from their sacs. This painful condition can cause your dog to act fearful or angry. Your vet will wash out the sacs and give your dog antibiotics.

An untreated infection will develop into an abscess (a swollen, tender mass of pus) and could break open. Your vet will open and drain the abscess and usually prescribe antibiotics and anti-inflammatory drugs. Daily warm compresses can help, too.

If your dog keeps having problems, your vet may want to remove their anal sacs with surgery. Ithe procedure may seem simple, but it can result in complications like fecal incontinence (when their poop leaks uncontrollably).

Put your dog on a healthy diet and make sure they get plenty of exercise. Small, obese dogs are at the highest risk of anal sac disease. Also, if you dog has problems with their anal sacs, have your vet check them at every checkup.