Anal sac inflammation in dogs

The anal sacs contain a fluid secretion that is both oily and smelly. If we were to look at the anal opening like a clock, the anal sacs sit at 4 and 8 o'clock, just under the skin between the external and internal sphincter muscles. The glands have a short exit, which opens into the dog's anus, one on each side of the opening.

The contents are partially emptied, a couple of drops, every time the dog poops. The anal sacs can also be emptied if the dog is frightened, or really scared. Then they can be emptied completely, of all their contents, and thus smell even worse. When the sacs are not emptied, the risk of inflammation and possible bacterial infection in them increases, which in turn leads to pain, swelling in the area and finally an abscess that bursts outwards through the skin.

Why do dogs have anal sac problems?

The anal sacs can fill up and remain unemptied for several reasons:

• Sometimes when the animal's faeces are soft (for example, after a few days of diarrhoea), the pressure needed to empty the sacs is lacking.
• It may also be because the dog was born with narrow passageways, or because the secretion becomes so dry that it dries and forms plugs in the passageways.
• Inflammation can also occur when the animal is constipated and does not poop.
• Dogs that are overweight or have allergies are at greater risk of suffering from anal sac inflammation.

When the anal sacs are not emptied daily, they remain full and the risk of inflammation increases. Anal sac inflammation is a painful condition that requires veterinary treatment. Overfilled bags can also result in the contents leaking out at times other than when the dog defecates, such as when the dog jumps on the sofa or car. Then the dog often smells very badly from behind.

Symptoms of anal sac inflammation

Your dog or cat can go their entire lives without ever having problems with their anal glands, but not all animals are so lucky. Normal anal discharge is grey to dark brown in colour and watery in consistency. Inflamed secretions can be all kinds of colours (red from blood or greenish-yellow from pus, indicating inflammation) and often viscous, but can also squirt out when the plug is released.

Some dogs seem unable to empty the glands completely on their own, causing the glands to become full, inflamed and uncomfortable. This usually results in the dog trying to fix the problem himself.

Symptoms that the dog's anal sacs are not emptied:

• The dog may drag its bottom along the floor or ground in an attempt to empty the anal sacs.
• The dog may lick or bite the area around the anus.
• The dog smells bad back there, or it leaks into the dog's sleeping area.
• You see blood stains or blood in the anus area.
• You see that the area is swollen or red.
• The dog seems to be in pain when it poops, maybe you see that the poop is narrower / flatter than usual.

If it gets really bad, irritation in and around the anal sacs, causing blockages in the exit passages, can lead to the development of abscesses. These boils can then rupture and break through the skin next to the anal opening, causing blood and pus to come out of the wound. A ruptured abscess may feel good for the moment for the animal when the pressure is released, but the dog is still in great need of treatment.

Treatment of anal sac inflammation

The first thing you can do - if you suspect that your animal is suffering from anal sac inflammation - is to wash the area, preferably with a hand shower, around the anal opening with lukewarm water twice a day. Two to five minutes each time is fine. You should see a vet if your dog continues to lick its bottom excessively, or to rub it's bottom along the floor.

How does a vet treat anal sac inflammation?

If you notice that your animal is not getting better, you should make an appointment with the vet. The vet will then empty the anal sacs. If it turns out that they are not inflamed or infected, that is usually enough for the animal to feel well again.

If the anal sacs or the area around the anus are inflamed, the vet may recommend anti-inflammatory and pain-relieving drugs until the worst is over. It is very rare that the vet considers your animal to need antibiotics in these cases.

If there has been a blockage, or if abscesses have formed, then the vet might need to flush the anal sacs.

If the situation is serious, and the dog is in a lot of pain, this may be because an abscess has formed. The vet may then have to sedate or anaesthetise the dog before opening the abscess, letting the us out and flushing it clean.

After the visit, the animal owner usually receives instructions about new washes/shower treatments of the anal area to prevent new problems from arising, as well as book a return visit to ensure that the anal sacs are functioning as usual again.

How to prevent problems with the anal sacs

If your animal has had recurrent problems with the anal sacs, it may be time to change the diet. Dog food rich in fibre sometimes helps to get the anal sacs in order. 

It is not advisable to empty the anal sacs if the animal is not showing symptoms, as this may contribute to the animal not emptying them in a normal way. Individual animals that cannot empty their anal sacs themselves, however, need continuous help with emptying. Let your vet assess this.

If the animal has recurring problems with the anal sacs and no solutions recommended by the veterinarian have helped, then a last resort may be surgery to remove the anal sacs. Your vet can guide you if this option needs to be considered.

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