Why Do My Dog’s Anal Glands Smell? Signs Your Dog May Have Impacted Anal Glands

In this article, Hannah Godfrey, our in-house animal nutritionist, discusses what to do if your dog’s anal glands smell, causes and symptoms, and the best food for dogs with anal gland issues. 

Does your pup scoot their bottom along the ground? Or maybe they excessively lick around their anus area? Or have you noticed some pretty foul-smelling fluids escaping from your dog’s anus?

These could be signs that your dog is experiencing an anal gland issue. 

What are the anal glands? Your dog has two anal glands which are small oval-shaped sacs. They sit on either side on the anus and their job is to produce a fluid that has an odour specific to them. Typically, this fluid is expressed from the anal glands when your dog poops and it is thought that it may also be used for territory marking. 

dog in grass                                                                           Photo by Mia Anderson

Most dogs can naturally express their anal glands. However, if a dog is unable to naturally express them then fluid builds up in the glands which causes them to swell and results in a block, referred to as anal gland impaction. This can go on to cause infections or abscesses and is referred to as anal succulitis. 

In this post, impacted anal glands will refer to both impaction AND succulitis.  

What are the signs of impacted anal glands?

  1. Your dog is scooting their bottom on the ground 
  2. Difficulty pooping and/or diarrhea
  3. Scratching and licking around the anal region
  4. Blood or pus visible in their feces or around the anus
  5. Foul or pungent “fishy” odour 

What are the causes for impacted anal glands? There are various reasons for impacted anal glands in dogs. These can include:

  • Allergies
  • Chronic skin conditions
  • Diarrhea or constipation
  • Breed and size
  • Obesity 
  • Poor diet

                                                                  Photo by Nikolay Tchaouchevdog walking down road

How can I help to prevent impacted anal glands in my dog? There are several ways in which you can help prevent the occurrence of impacted anal glands for your pup. The first step is to identify the potential causes or risk factors your pup may be exposed to. 

Ultimately, your dog’s diet can be a big risk factor. We have outlined some helpful tips for the major causes for impacted anal glands and how changes to their diet may help for you here:

1. Allergies

By reducing exposure to allergies, you can help reduce the subsequent inflammation and physiological responses which can result in impacted anal glands. 

You can read more about food allergies and intolerances here: Understanding Allergies in Dogs and How to Help.

For environmental allergies, a diet that is rich in anti-inflammatories and antioxidants may be beneficial. Consider our Rosemary Venison or Coconut Chicken recipes which are jam-packed with soothing nutrients to reduce allergies. Seasonal or environmental allergies may also require veterinary guidance and medications. 

2. Chronic Skin Conditions

You may not know, but the anal glands are considered part of the skin. Therefore, skin disorders will also present on the anal glands. 

While chronic skin conditions are often a result of allergies or intolerances, they can also be due to environment (dry atmosphere, etc) or may be due to dermatitis. Skin conditions may benefit from a dietary change such as incorporating hydration, fatty acids, antioxidants, and digestible proteins. 

dog in nature                                                                                    Photo by Jamie Street

Choosing fresh pet food can help increase your dog’s water intake due to its high moisture content. Ensuring a range of healthy fats is also important for your pet’s skin. You can read more about healthy fats here: What Does “Healthy Fat” Mean for Pets?

In addition, fresh pet food is highly digestible, especially compared to dry foods, which can help ensure your pet is getting sufficient protein. Proteins are crucial for healthy skin and coat!  

Chronic skin conditions may also benefit from medications that can be prescribed by your veterinarian. 

3. Diarrhea or Constipation

Diarrhea or loose stool can be a risk factor for impacted anal glands. Loose or soft stools will not allow the glands to express naturally when defecating. This results in a build-up of fluids in the anal glands causing impaction. 

Similarly, when no stool is passed due to constipation, the anal glands will not receive their “cue” to express fluids.

There are various causes for diarrhea and constipation in dogs including:

  • Low fibre intake or poor diet
  • Untreated gastrointestinal diseases (i.e. inflammatory bowel disease)
  • Food allergies or intolerances
  • Infections
  • Stress

Treating the underlying cause for diarrhea or constipation is critical for reducing diarrhea or constipation and thus preventing anal gland impaction. 

Diet is often a major culprit for diarrhea and constipation. Dietary fibres are important for providing bulk to the stool and can also help with the movement of stool. 

You can read more about fibre here: Dietary Fibre for your Pets

4. Breed and Size

Certain dog breeds may be at a greater risk for impacted anal glands than others. Specifically, small breeds are considered to have the highest risk compared to large dog breeds. However, certain large breeds may also have greater risks. 

The Chihuahua, Cavalier King Charles Spaniel, Labrador, and German Shephard are all at high risks. 

chihuahua                                                                           Photo by Angelina Litvin

For these breeds, prevention of diarrhea, constipation, skin concerns, and other risks for impacted anal glands are of importance. 

5. Obesity

Obesity is one of the most common health concerns for dogs and can lead to other detrimental consequences such as diabetes and arthritis. However, impacted anal glands can also be a consequence of obesity!

How? There are two ways in which obesity can increase anal gland impaction. 

The excess fat depots can compress the ducts of the anal glands. This can cause retention of the contents in the anal glands. 

In addition, obesity can result in reduced muscle tone, even the muscles of the anus. This weakens the ability to express their anal glands naturally. 

6. Poor Diet

And of course, diet is a major player for anal gland impaction. A poor diet can effect muscle tone, body composition, gut motility, the microbiome, and stool quality. All of which can then affect the anal glands’ ability to express. 

What’s the best food for dogs with anal gland issues? Here are some things to be looking for in a diet targeted for preventing impacted anal glands:

  1. Fibre: Both soluble and insoluble fibres are important for gut health, microbiome health, and stool quality. Fibre is one of the few nutrients that have been well studied for their efficacy in preventing impacted anal glands successfully! 
  2. Moisture content: Fresh, gently cooked pet food often has a high moisture content (>70% moisture). Hydration is imperative for gut health, digestion, and stool quality!
  3. Healthy fats: A good ratio of omega 6 to omega 3 fatty acids provides an anti-inflammatory effect which may be beneficial for preventing anal gland impaction.
  4. High digestibility: Gently cooked pet foods are considered to be more digestible than other types of pet food. A high digestibility improves the ability of your pet to absorb all those nutrients! This is important for their overall health but also for the gut and microbiome!

How can I treat impacted anal glands? If your pup is currently experiencing impacted anal glands then it is important to seek out veterinary care. Expressing the anal glands is the primary step for treating impacted anal glands. This should be done by a trained professional to prevent rupturing the anal gland or further spreading an infection. 

two golden retrievers                                                                            Photo by Gulyás Bianka

If the glands are infected then general anesthetic may be required to reduce any pain while expressing the glands.

Flushing the glands with an antiseptic fluid may be required. Other treatments may include warm packs, anti-inflammatory medications, antibiotics in the case of bacterial infection, or corticosteroids. 

Prevention is best! 

Once you’ve confirmed your dog has anal gland issues and your pup receives the appropriate treatment, the focus should be shifted to the preventative steps above. Only in rare cases is it usually recommended to have the anal glands surgically removed as this can cause other health concerns. 

And, if your dog does not currently have anal gland issues, this guide can be used to prevent any future issues.

Other articles you might like:
Understanding Allergies in Dogs and How to Help
What Does Healthy Fat Mean for Pets?
Ferment on This: Dietary Fibre for Your Pets

Written by: Hannah Godfrey
Animal Nutritionist
BSc.H. | MSc. Animal Nutrition


  1. Corbee et al. (2022). A Cross-Sectional Study on Canine and Feline Anal Sac Disease. Animals
  2. Ehrenzweig (2018). Novel Fiber-rich Supplement Effective for Prevention and Treatment of Acute, Episodic and Chronic Anal Gland Disease in Dogs and Cats. Intern J Vet Anim Med. 
  3. Van Duijkeren (1995). Disease conditions of canine anal sacs. J Small Anim Pract. 
  4. Algya et al., (2018). Apparent total-tract macronutrient digestibility, serum chemistry, urinalysis, and fecal characteristics, metabolites and microbiota of adult dogs fed extruded, mildly cooked, and raw diets. J Anim Sci.