Updated: Mar 3, 2021
Anal gland impaction is when the glands inside a dog's anus become full and blocked, causing the dog irritation and discomfort.
What are anal glands?
The anal glands are paired sacs that sit just inside the anus. They secrete a strong smelling liquid, which plays a role in territory marking.
Normally, the contents of the anal glands are squeezed out as a firm stool passes through the rectum. If they're not emptied properly, they can become over full and uncomfortable for the dog.
What are the signs of anal gland impaction?
You might notice a strong fishy odour. Blocked anal glands are irritating and painful and so your dog may also:
Sit down suddenly
Turn to look at their bottom
Lick or chew their bottom
Repeatedly lick or chew another area of skin nearby e.g. the thigh or hip
Straining or difficulty passing faeces
What should I do if I think my dog has blocked anal glands?
Left untreated, blocked anal glands can develop into more serious issues such as infections and abscesses. If you suspect your dog has blocked anal glands, you should get them checked out by a vet.
The vet will examine your dog’s bottom and express (empty) the glands for them.
Do not try to empty the glands yourself as you pain cause further pain and damage.
Will my dog need any other treatments or surgery?
Your dog may also require additional treatment such as antibiotics (given in 20% of cases) and pain relief (12% of cases).
The need for surgical removal of the anal sacs is uncommon (1%) and is reserved only for chronic and complicated cases.
How quickly will the signs resolve?
Relief from expressing impacted anal glands can be instantaneous, although dogs will experience some degree of irritation for up to 24 hours afterwards.
However, recurrence is common, with one study reporting that symptoms can reappear after around 3 weeks and that repeat emptying is required every 2 months.
How can I stop my dog's anal glands getting blocked?
Prevent your dog becoming overweight as obesity increases the risk of anal gland impaction.
Feed your dog a good quality, complete diet. This will not only keep them in shape, but might help ensure their stools are firm enough to empty the glands as they pass through the rectum.
If your dog repeatedly suffers from anal gland impaction, it is thought that adding fibre to their food might help. However, evidence for the role of diet in preventing and treating anal gland disorders is, lacking.
How common are anal gland problems?
A study published in 2021 reported that non-cancerous anal gland disorders affect 4.4% of dogs. The infographic on the right provides more details about the study findings.
Do all dogs get anal gland problems?
All dogs can get anal gland disorders but there are certain factors which increase the risk. These include:
Age - elderly animals are more commonly affected
Body condition - being overweight increases the risk
Breed - certain breeds have been shown to be more commonly affected. These include the cavalier King Charles spaniel, King Charles spaniel, cockapoo and brachycephalic (flat-faced) dog breeds. Other breeds are less commonly affected. These include boxers, German Shepherds, lurchers, Staffordshire bull terriers, border collies and labradors.
As always, always speak to your vet if you have any concerns about your dog's health.
O'Neill, DG, Hendricks, A., Phillips, JA., Brdbelt, DC., Church, D.C., Loeffler, A. (2021). Non‐neoplastic anal sac disorders in UK dogs: epidemiology and management aspects of a research‐neglected syndrome. Early view e203. doi.org/10.1002/vetr.203
James DJ, Griffin CE, Polissar NL, Neradilek MB. (2011). Comparison of anal sac cytological findings and behaviour in clinically normal dogs and those affected with anal sac disease. Vet Dermatol. 22(1):80-7. doi: 10.1111/j.1365-3164.2010.00916.x. Epub 2010 Nov 29. PMID: 21114559.