What Are Dog Anal Glands?

Every dog has two anal glands, also called anal sacs, positioned just inside the anus at roughly the four o’clock and eight o’clock positions. Each gland is about the size of a small grape in medium-sized dogs, though the size varies with breed and body weight. The glands are lined with sebaceous and apocrine tissue that continuously produces a thin, oily, and extremely pungent fluid.

Under normal circumstances, the anal glands empty naturally each time a dog has a bowel movement. The pressure of a firm stool passing through the anal canal compresses the glands and forces the fluid out through tiny ducts that open just inside the anal rim. This fluid carries a unique chemical signature, which is why dogs instinctively sniff each other’s rear ends — they are reading scent information as distinctive as a fingerprint.

When the system works properly, most owners never notice the anal glands at all. Problems arise when the glands do not empty completely, leading to a buildup of fluid that can thicken, become impacted, and eventually cause pain, swelling, and infection. Understanding how these glands function is the first step toward recognizing when something has gone wrong. If you are considering adopting a dog, learning about common health concerns like anal gland issues will help you provide better care from day one.

Signs of Anal Gland Problems

Dogs cannot tell you when their anal glands are bothering them, but their behavior speaks clearly once you know what to look for. The signs tend to appear gradually and escalate if the underlying issue is not addressed.

Scooting

The most recognizable sign of anal gland discomfort is scooting — when a dog drags its rear end across the floor, carpet, or grass. This behavior is an attempt to relieve the pressure or irritation caused by full or impacted glands. While occasional scooting can happen for other reasons, including intestinal parasites or skin irritation, persistent or frequent scooting strongly suggests an anal gland issue. Dogs may scoot after bowel movements or seemingly at random throughout the day.

Excessive Licking and Biting

Dogs with uncomfortable anal glands often lick or bite at their rear end excessively. You may notice your dog turning to lick the area under the tail repeatedly, sometimes causing redness, hair loss, or raw skin around the anus. Some dogs will also chew at the base of their tail or their hindquarters in an effort to address the discomfort. If you observe this behavior alongside scooting, anal gland problems should be high on the list of suspected causes.

Fishy Smell

Anal gland fluid has a distinctive, strong odor that most people describe as fishy or metallic. Under normal conditions, the small amount released during bowel movements goes unnoticed. However, when the glands are overly full, leaking, or infected, the smell can become noticeable even from a distance. You may detect it on your dog’s bedding, on furniture where the dog sits, or as a sudden, intense burst of odor when the dog is startled or anxious. Stress and fear can cause involuntary release of anal gland fluid, which is why some dogs emit a fishy smell during veterinary visits or thunderstorms.

Other Warning Signs

Additional signs include visible swelling or redness near the anus, difficulty sitting or reluctance to sit down, straining during bowel movements, blood or pus near the anal area, and a sudden change in the appearance or consistency of stool. A dog that yelps when sitting or shows signs of pain when the tail area is touched should be examined promptly.

Impaction vs. Infection vs. Abscess

Anal gland problems exist on a spectrum, and understanding the difference between impaction, infection, and abscess helps you gauge the severity of the situation and respond appropriately.

Anal Gland Impaction

Impaction is the most common and least severe form of anal gland trouble. It occurs when the fluid inside the glands thickens and becomes too dense to express naturally during bowel movements. The glands fill up, stretch, and cause increasing discomfort. Impaction is often the result of soft stools that do not apply enough pressure to the glands, a low-fiber diet, or simple anatomical predisposition. Most impactions can be resolved with manual expression — a relatively simple procedure performed by a veterinarian or trained groomer.

Anal Gland Infection (Sacculitis)

If an impacted gland is not addressed, the stagnant fluid can become a breeding ground for bacteria, leading to infection. An infected anal gland is noticeably more painful than an impacted one. The fluid may change from its normal brownish color to yellow or green, sometimes with traces of blood. The area around the anus may appear red and swollen, and the dog may show signs of systemic illness, including lethargy, reduced appetite, or a low-grade fever. Infected anal glands require veterinary treatment, which typically includes manual expression, antibiotics, and sometimes flushing the glands with an antiseptic solution.

Anal Gland Abscess

An abscess is the most serious stage of anal gland disease. It develops when an untreated infection causes a pocket of pus to form within or adjacent to the gland. The skin over the affected gland becomes hot, swollen, and extremely tender. In some cases, the abscess ruptures through the skin near the anus, creating an open, draining wound that is painful and prone to further infection. A ruptured anal gland abscess is a veterinary emergency. Treatment involves draining the abscess, thoroughly cleaning the area, administering antibiotics, and providing pain management. Some dogs with recurring abscesses may require surgical removal of the affected gland.

When to Express Dog Anal Glands

Not every dog needs manual anal gland expression. Many dogs go their entire lives without any intervention because their glands empty naturally with each bowel movement. Expression should only be performed when there is a clear indication that the glands are not emptying on their own.

The clearest signal is behavior. If your dog is scooting, licking the area excessively, or producing a persistent fishy smell, the glands likely need attention. Some veterinarians recommend checking the glands during routine wellness exams, especially for breeds known to have frequent problems. However, expressing anal glands on a rigid schedule without evidence of fullness is generally not recommended. Over-expression can cause irritation and inflammation that may actually increase the likelihood of future problems by weakening the tissue surrounding the ducts.

If you notice any signs of infection or abscess — significant swelling, discharge, bleeding, or your dog showing signs of pain — skip at-home checks entirely and go directly to a veterinarian.

Professional Expression vs. DIY

There are two approaches to anal gland expression: external and internal. Understanding the difference is important when deciding whether to handle this at home or leave it to a professional.

Professional Veterinary Expression

Veterinarians and veterinary technicians perform internal expression, which is the more thorough and effective method. Wearing a glove, the professional inserts a finger into the rectum and gently compresses each gland between the internal finger and an external thumb. This technique allows them to fully empty the glands and assess the consistency and color of the fluid, which provides diagnostic information about the health of the glands. A veterinary professional can also identify early signs of infection, tumors, or structural abnormalities that would not be apparent externally. The cost of professional expression typically ranges from 20 to 50 dollars and is often included as part of a wellness exam.

DIY External Expression

Some groomers and experienced dog owners perform external expression, which involves applying gentle pressure to the outside of the glands through the skin. This method can relieve mild fullness but is less effective at completely emptying the glands, particularly if the fluid has thickened. Incomplete expression can leave residual material behind, which may worsen impaction over time.

If you choose to attempt expression at home, proceed with extreme caution. Use disposable gloves and have paper towels and warm water ready. Apply gentle, steady pressure — never force or squeeze aggressively, as this can rupture the gland or damage surrounding tissue. If the fluid does not come out easily, or if the dog shows signs of significant pain, stop immediately and consult your veterinarian. For most dog owners, professional expression is the safer and more reliable option.

Diet and Fiber for Prevention

Diet is the single most influential factor in preventing anal gland problems. The connection is straightforward: firm, well-formed stools apply natural pressure to the anal glands during defecation, promoting healthy emptying. Soft or loose stools do not generate enough pressure, allowing fluid to accumulate.

Increasing dietary fiber is the most effective nutritional strategy for supporting anal gland health. Fiber adds bulk to the stool, which improves its consistency and firmness. There are several safe, practical ways to add fiber to your dog’s diet.

Pumpkin is one of the most popular and effective fiber sources for dogs. Plain canned pumpkin — not pie filling — provides soluble fiber that helps regulate digestion and firm up stools. One to four teaspoons per day, depending on the size of the dog, is a common recommendation.

Psyllium husk is another excellent fiber supplement. A small amount mixed into food can significantly improve stool quality. Start with a quarter teaspoon for small dogs and work up gradually to avoid gas or bloating.

Sweet potatoes, green beans, and carrots also provide fiber along with valuable vitamins and minerals. These can be cooked, mashed, and mixed into regular meals as a supplement.

Beyond fiber, maintaining a healthy weight is critical. Overweight dogs are significantly more prone to anal gland problems because excess fat in the perianal area can physically interfere with the glands’ ability to empty. Dogs that are at a healthy weight, eating a high-quality diet with adequate fiber, and producing firm stools are far less likely to develop anal gland issues. Adequate hydration also plays a supporting role, as dehydration can contribute to harder, smaller stools that do not effectively compress the glands.

Dog Breeds Prone to Anal Gland Problems

While any dog can develop anal gland issues, certain breeds experience them at a disproportionately higher rate. Small and toy breeds are the most commonly affected, likely due to the combination of smaller duct openings, softer stool consistency, and a higher rate of obesity within these populations.

Breeds frequently cited by veterinarians as being prone to anal gland problems include Chihuahuas, Toy and Miniature Poodles, Cocker Spaniels, Beagles, Basset Hounds, Lhasa Apsos, and Shih Tzus. Bulldogs and French Bulldogs also appear on the list, as their compact body structure can contribute to gland emptying difficulties. Dachshunds, with their long bodies and short legs, are another breed that commonly presents with anal gland concerns.

Among larger breeds, Labrador Retrievers and German Shepherds are occasionally affected, often in connection with food allergies or chronic soft stools rather than structural predisposition. If you are researching breeds before bringing a dog into your family, our dog breeds directory provides detailed profiles that cover health considerations, including breed-specific vulnerabilities.

Regardless of breed, dogs with chronic allergies — particularly food allergies — are at elevated risk. Allergies cause inflammation throughout the body, including in the tissues around the anal glands, which can lead to swelling that narrows the ducts and prevents normal drainage. Managing allergies through diet, medication, or environmental changes can have a direct positive impact on anal gland health.

When to See the Vet

Many mild anal gland issues can be managed with dietary changes and occasional professional expression. However, there are situations where veterinary attention is not optional and delay can lead to serious complications.

See your veterinarian promptly if your dog shows any of the following: visible swelling, redness, or a lump near the anus; discharge of blood, pus, or foul-smelling fluid from the anal area; a wound or opening near the anus that appears to be draining; signs of significant pain such as crying when sitting, reluctance to walk, or snapping when the hind area is touched; persistent scooting or licking that does not improve after expression; fever, lethargy, or loss of appetite alongside anal gland symptoms; or any recurrence of problems within a few weeks of the last expression.

Your veterinarian may recommend additional diagnostics, including a rectal exam, cytology of the gland fluid, ultrasound, or biopsy if there is concern about abnormal growths. While rare, anal gland adenocarcinoma — a type of cancer — does occur in dogs and can initially present with symptoms similar to chronic impaction or infection. Early detection significantly improves treatment outcomes.

For dogs that experience chronic, recurring anal gland problems despite dietary management and regular expression, your veterinarian may discuss anal sacculectomy — the surgical removal of one or both anal glands. This is a permanent solution that eliminates the source of the problem, though it carries risks including potential fecal incontinence and should only be considered when conservative management has failed. If you are looking to adopt a dog with known anal gland issues, discuss a long-term management plan with your veterinarian so you are prepared from the start.

Frequently Asked Questions

How often should dog anal glands be expressed?

There is no universal schedule. Some dogs never need manual expression, while others require it every four to six weeks. The frequency depends on the individual dog’s anatomy, diet, stool consistency, and overall health. Express anal glands only when there are signs of fullness or discomfort rather than on a fixed calendar. Over-expression without cause can irritate the glands and create a cycle of dependency where the glands lose the ability to empty naturally.

Can I express my dog’s anal glands at home?

External expression can be performed at home, but it requires care and a gentle approach. Internal expression, which is more thorough, should be left to a veterinarian or trained professional. If you are uncomfortable with the procedure, if the fluid does not come out easily, or if your dog reacts with pain, stop and schedule a veterinary appointment. Improper technique can cause bruising, rupture, or push bacteria deeper into the tissue.

Why do my dog’s anal glands keep filling up?

Recurring fullness is typically caused by one or more contributing factors: a low-fiber diet that produces soft stools, chronic allergies that cause inflammation around the glands, obesity that adds pressure to the perianal area, or an anatomical predisposition in certain breeds. Addressing these root causes — particularly by increasing dietary fiber and managing allergies — is more effective than relying solely on repeated manual expression.

What does infected anal gland fluid look like?

Healthy anal gland fluid is typically thin, brownish, and oily. Infected fluid may appear thick, pasty, yellow, green, or gray. It may also contain visible blood or have a significantly more intense and foul odor than normal. If you notice any of these changes during expression, or if the area around the gland is red and swollen, seek veterinary treatment. Early intervention with antibiotics can prevent the infection from progressing to an abscess.

Do anal gland problems go away on their own?

Mild fullness may resolve on its own if the dog produces a firm bowel movement that applies enough pressure to empty the glands naturally. However, true impaction, infection, and abscesses do not resolve without intervention. Waiting for these conditions to improve on their own allows them to worsen, increasing pain for the dog and the complexity of treatment. If your dog is showing signs of anal gland discomfort that persist for more than a day or two, seek professional care.