Anal Glands

What are anal glands?

Anal Glands, also known as Anal Sacs,  are small scent glands situated either side and slightly below the anus of many mammals including dogs and cats.

They are a pair of sacs located on either side of the anus between the external and internal sphincter muscles.  They enable the animals to mark their territory and identify other dogs.

These sacs are emptied every time the dog defecates a healthy firm stool and does not require regular cleaning.

The fluid scent inside gland sacs is unique per dog, it is their signature. This is why dogs first smell the posterior of other dogs when they meet.


Diet plays an important role in the health of anal glands.  High Fibre food adds bulk to the stool but the variety of food is also critical to help maintain a balanced diet.

Anal glands are not normally cleaned as part of a dog grooming session.  These glands should not be interfered with unless the dog in question has a blocked gland.

In soft stools, insufficient pressure is exerted in anal glands, therefore these may fail to empty.   In most cases, these can be painful for the pet and glands may need to be expressed (i.e. cleaned) by the dog owner, dog groomer or the Vet.

This technique is called anal sac expression and should only be carried out by fully trained person to help maintain good hygiene and reduce discomfort.

Symptoms of discomfort and signs of blocked anal sacs:

  • Dog drags its posterior across the floor, also known as scooting.
  • Excessive licking of the anus.
  • Soreness and red swollen anal  area may be hidden in long hair dogs.
  • Constant position changes from standing to sitting down or difficulty in sitting down. for long periods of time.
  • Chasing its tail or trying to bite its anal area.
  • Bad odor even after a bath.
  • Constant itching and scratching its posterior.
  • Regular soft stools or diarrhea.
  • Dogs that do not defaecate regularly.
  • Overweight dogs
If your dog or pet is showing any of above symptoms, please consult a trained person to express its anal glands. 

When symptoms persist the dog may require a repeat session or to visit the local Vet for other possible causes.     If in doubt, check it out!

Scooting highlighted above is a common symptom but also check for tape worms, which may be easily treated with antibiotics, try worming treatment regularly.Please note that dog owners should not attempt to carry out this procedure without training as it may cause more pain than relieve for the dog.

In case of an infection, it can also cause further damage if the person expressing the anal sac is not trained or persists with an incorrect method of expressing.

Dog must be adequately restrained to eliminate the risk of injury to person or dog.
It is also important to note that excessing cleaning of anal glands may cause long term damage like fecal continence dysfunction.

The anal gland expression is a procedure only required if it is not occurring naturally when dog defecates or if dog restarts scooting across the floor.

If left untreated, it may cause unnecessary pain and lead to a serious problems:

  • Swollen anal sacs or bright red coloured anal area.
  • Gland abscess (may be treated with antibiotics if diagnosed early).
  • Blood in stools.
  • Drainage from the anal area.
  • Gland rupture (hole in the skin of anal sac).
  • Gland removal.
  • Tumors that requires  surgery.


There are to two methods  to express the anal sacs:

  1. External anal sac expression ( the most common)
  2. Internal anal sac expression

External anal sac expression is accomplished by squeezing the gland until its contents are released.

Internal anal sac expression is addressed by pushing  sac with thumb and inserting index finger inside anal area.

Gloves and protective clothing must be worn for both methods.  This procedure should be carried out in an clean and tidy environment.  Also the fluid may release quickly and go everywhere.  Have a clean cloth ready to hold the fluid and protect yourself and the other from getting dirty.

Fluid released from anal glands has a strong smell, it can be watery or thicker.  Colour may vary: white, cream, brown and black. If pasty and bloody, consult the vet.

In cats, one of the symptoms is for cat to defecate outside the litter tray.   Once the anal glands are expressed, normally cats resume to use litter tray.

Also cats can often lick the fur off under the posterior area or tail.  If the glands have been expressed and the problem persists please seek advice from the Vet.

Please note that the information provided here is for generic guidance purposes only.  It does not replace the advice from a qualified Vet.
If you are concerned with your pet, always consult the Vet.By: Isabel Robson and Ana Raquel Almeida

 How to clean anal sacs – Free video