What Causes Anal Sac Block in Dogs?

Anal sac blockage can be miserable for your pooch.
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Every dog has two anal sacs, also called anal glands, located under the skin on either side of the anus. While members of the wild dog family used to use these glands for scent marking territory, in domesticated dogs the glands serve no real purpose. The glands by design express themselves when a dog has a bowel movement -- but when they clog, they become uncomfortable for your pet and may require medical attention.

Blocked Glands

Anal glands have the potential to become blocked if fluid builds up and becomes too thick to drain naturally. When this obstruction goes untreated, potential for infection to develop and for the gland to abscess exists. This presents as fluid, sometimes bloody, draining from the dog’s anal region. Depending on the severity of the situation, your dog may need both full expression and antibiotic treatment.

Symptoms of Blockage

If your dog is experiencing any type of problem with his anal sacs, you may see him drag his bottom across the ground in an effort to express the glands himself. He may also bite and lick at the area to alleviate itching. If the glands have reached a point of impaction, you may notice the area becoming red and inflamed, possibly swollen and warm to the touch. A bad smell coming from the rear of your pooch is also an indication that the glands need attention.

Treatment Options

Expressing clogged anal sacs is the most common form of treatment for blocked glands. You can do this yourself by using a gloved finger to gently palpitate the glands on either side of the anus or by inserting a finger into the rectum and expressing the glands internally. It may take several attempts before the sacs are completely evacuated. Many pet owners find this to be distasteful and prefer to take their dog to a vet or a professional groomer to have it done.

Preventative Measures

Talk to your vet about your dog’s fiber requirements. Sometimes adding fiber to a pup’s diet can help reduce the recurrence of anal sack blockage. Dropping a few pounds can help reduce the occurrence of problems, as overweight dogs are more likely to suffer from this disorder. Your vet may recommend surgically removing the glands -- a procedure called a sacculectomy -- if your dog has regular, ongoing problems with them.