# Anal Fistula in Dogs: Perianal Fistula Guide An anal fistula in dogs is a tunnel-like tract that forms between the inside of the rectum and the skin around the anus. The medical term for the condition is perianal fistula, and an older name you may still see in veterinary textbooks is anal furunculosis. The single most important fact for owners is this: perianal fistula in dogs is not an infection. It is an immune-mediated disease in which the dog's own immune system attacks the skin and tissues around the anus, and it is strongly linked to genetics in German Shepherd Dogs [1][2]. The disease is painful, progressive, and often foul-smelling. It causes straining to defecate, licking at the rear end, and open, draining sores that can spread around the entire circumference of the anus. Treatment has improved dramatically over the past two decades, and most dogs can be managed, but the condition is chronic and frequently recurs. This guide explains what causes perianal fistula in dogs, how veterinarians diagnose and stage it, and what the evidence says about medical and surgical treatment. **Owner-facing triage summary:** If your dog has open sores, a foul odor, or a discharge near the anus, or if your dog cries or strains when passing stool, see a veterinarian promptly. This is not a condition that resolves on its own, and antibiotics alone will not fix it. Early treatment produces the best outcomes. This article is educational and is not a substitute for veterinary diagnosis or treatment. ## At a Glance: Perianal Fistula in Dogs | Feature | What Owners Should Know | |--|--| | What it is | Immune-mediated inflammation and ulceration of perianal tissue, with sinus tracts or rectocutaneous fistulas [3] | | What it is not | Not a primary bacterial infection, though bacteria can colonize the wounds | | Most affected breed | German Shepherd Dog, accounting for over 80% of reported cases [2] | | Typical age | Middle-aged to older dogs, though homozygosity for a risk gene is linked to earlier onset [2] | | Classic signs | Straining to defecate, vocalizing during defecation, licking the rear, foul odor, open draining sores | | First-line treatment | Cyclosporine, an immunosuppressive medication [4] | | Duration of treatment | Often weeks to months, with a mean of about 8.8 weeks in one study [5] | | Common side effects | Increased coat turnover and transient vomiting [6] | | Role of antibiotics | Not effective as sole therapy | | Role of surgery | Reserved for refractory cases or residual lesions after medical treatment [7][4] | | Prognosis | Manageable but recurrent. Owner-reported improved quality of life is high after surgical resection [7] | ## What Is a Perianal Fistula? A perianal fistula is a chronic inflammatory disease of the tissues surrounding the anus. The word "fistula" describes an abnormal channel. In this disease, inflammation destroys the skin and deeper tissue around the anus, creating ulcers and narrow tracts that can tunnel from the rectal lining out through the skin. These tracts are called rectocutaneous fistulas [3]. The condition is also called anal furunculosis. "Furunculosis" refers to the boil-like nodules that form as the tissue breaks down. Despite the name, the process is not driven by a boil-causing infection. It is driven by immune dysregulation. The lesions are typically found in a circular pattern around the anus. In severe cases, they can extend outward onto the surrounding skin and inward into the anal canal and rectum. The tissue becomes thickened, ulcerated, and painful. ## Why Perianal Fistula Is an Immune-Mediated Disease, Not an Infection Owners often assume that a foul-smelling, draining wound must be infected. That assumption leads to a common and costly mistake: treating perianal fistula with antibiotics alone. Antibiotics do not resolve the disease because bacteria are not the root cause. The evidence for an immune-mediated cause is strong and comes from several directions. ### Genetic evidence German Shepherd Dogs account for more than 80% of all reported cases of anal furunculosis, which points to a genetic basis for susceptibility [2]. Researchers have identified a highly significant association between the disease and a specific dog leukocyte antigen allele, DLA-DRB1*00101. Dogs carrying this allele have roughly five times the odds of developing the disease, and dogs that are homozygous for it tend to develop the disease earlier in life [2]. A separate study examined the tumor necrosis factor alpha gene region and found an association that appeared to be secondary to linkage with DLA-DRB1, reinforcing the central role of the major histocompatibility complex in disease susceptibility [8]. A genome-wide association study in German Shepherd Dogs identified the ADAMTS16 and CTNND2 gene regions as most significantly associated with disease, and also implicated members of the butyrophilin protein family, which are important in intestinal inflammatory regulation [1]. A study of pattern recognition receptor genes found that German Shepherd Dogs have highly restricted genotypes in these immune genes, likely the result of selective breeding, which may influence innate immune responses in the breed [3]. No significant association between these specific receptor polymorphisms and the disease was found, but the restricted genetic diversity itself is relevant to how the breed's immune system functions. ### Tissue-level evidence Biopsies of perianal fistula lesions show a consistent pattern of T cell-mediated inflammation. Interleukin-2 was detected in 11 of 15 affected dogs but in only one of 24 control dogs, and interferon-gamma was detected in 14 of 15 affected dogs but in none of the controls [9]. This is a T helper type 1 cytokine profile, the signature of a cell-mediated immune attack. Interleukin-2 and interferon-gamma mRNA levels are significantly elevated in affected tissue compared with control perianal tissue [10]. Matrix metalloproteinases 9 and 13, enzymes that break down tissue matrix and are primarily produced by macrophages, are also significantly increased in lesions [11]. This suggests that tissue destruction results from aberrant macrophage activation, possibly triggered by interferon-gamma from T helper type 1 cells [11]. ### Clinical response evidence The strongest practical evidence for an immune-mediated cause is that immunosuppressive drugs resolve the disease. Cyclosporine, which specifically suppresses T cell activation, produced complete resolution in 69% of dogs and improvement in another 27% in one study of 26 dogs [5]. A medication that works by suppressing the immune system would not be expected to resolve a primary bacterial infection. ### What about bacteria? Bacteria, particularly Staphylococcus intermedius, are commonly found in these wounds, but they are secondary colonizers rather than the cause. A study of the humoral immune response found that dogs with anal furunculosis had elevated antistaphylococcal IgG, similar to dogs with other forms of deep skin infection, but normal levels of antistaphylococcal IgA [12]. This pattern is consistent with secondary bacterial involvement in a wound, not with a primary staphylococcal disease. ## Anatomy and Physiology: Why the Perianal Area Is Vulnerable The anus sits at the end of the gastrointestinal tract and is surrounded by a ring of tissue that includes skin, subcutaneous fat, the external anal sphincter muscle, and the anal sacs. The anal sacs are two small pouches located on either side of the anus that empty through ducts onto the perianal skin. This region is under constant mechanical stress. Every bowel movement stretches and compresses the tissue. The skin here is thin and moist, and it is exposed to fecal bacteria. When the immune system attacks this tissue, the combination of inflammation, mechanical stress, and bacterial exposure produces the characteristic ulcers and fistulas. The proximity of the anal sphincter muscle matters for treatment. Aggressive surgery can damage the sphincter and cause fecal incontinence. This is one reason medical management is preferred as the first-line approach. ## Causes and Risk Factors ### Breed The German Shepherd Dog is by far the most commonly affected breed [2]. This is not a mild predisposition. The breed accounts for the large majority of reported cases. ### Genetics The DLA-DRB1*00101 allele is a major risk factor [2]. The ADAMTS16 and CTNND2 gene regions and the butyrophilin family are also associated with disease [1]. The TNFA haplotype association appears to be secondary to linkage with DLA-DRB1 [8]. ### Age The disease most often affects middle-aged to older German Shepherd Dogs [2]. Dogs that are homozygous for the risk allele tend to develop the disease at a younger age [2]. ### Concurrent colitis There is an association between perianal fistula and [colitis in dogs](/knowledge/veterinary-medicine/clinical-methods/canine-colitis-diagnosis-management). In one study, 50% of dogs referred for treatment of anal furunculosis had a histopathological diagnosis of colitis [13]. Clinical signs alone cannot reliably distinguish which dogs have colitis, so the authors recommended that colonic biopsies be performed in all dogs presented with anal furunculosis [13]. This matters for treatment because colitis may complicate management. A study of German Shepherd Dogs with perianal fistulas and histological evidence of colitis found that treatment with immunosuppressive doses of prednisone and an alternative protein diet completely resolved fistulas in 33.3% of cases, improved them in another third, and left them unchanged in the final third [14]. ### Diet Dietary factors have been investigated as both a potential trigger and a treatment tool. An exclusive white fish and potato diet was used perioperatively in a surgical case series and was associated with a low rate of complications [15]. The role of diet in the underlying disease process is not fully understood, but dietary modification is part of the treatment landscape. ## Differential Diagnoses: What Else Looks Like a Perianal Fistula Several other conditions can produce sores, swelling, or discharge around the anus. Distinguishing them from perianal fistula is essential because the treatments are completely different. ### Anal sac adenocarcinoma This is the most important differential diagnosis. Anal sac adenocarcinoma is a malignant tumor of the anal sacs that can cause swelling, pain, and straining to defecate. It can also cause hypercalcemia, which produces increased thirst and urination. A veterinarian must rule out anal sac adenocarcinoma before treating for perianal fistula, because delayed cancer treatment has serious consequences. ### Anal sacculitis Anal sacculitis is inflammation or infection of the anal sacs. It causes scooting, licking, and pain on defecation. Unlike perianal fistula, anal sacculitis does not typically produce the characteristic circular ulcers and fistulous tracts. A retrospective study of 33 dogs with anal sacculitis specifically excluded dogs with perianal sinuses or fistulas, anal sac masses, or anal sac abscesses [16]. This distinction is important because the treatment for anal sacculitis is entirely different, often involving flushing and infusion of a steroid, antibiotic, and antifungal ointment [16]. ### Perianal tumors Other tumors of the perianal region, including perianal adenomas and adenocarcinomas, can cause swelling and discomfort. A veterinarian will palpate the area and may recommend imaging or biopsy. ### Other skin conditions Deep pyoderma, severe dermatitis, and other inflammatory skin diseases can occasionally affect the perianal area. The pattern and distribution of lesions help distinguish these from perianal fistula. ## How Veterinarians Diagnose Perianal Fistula Diagnosis is primarily clinical. A veterinarian can often make a presumptive diagnosis based on the appearance and location of the lesions, combined with the dog's breed and history. ### Visual examination The hallmark finding is ulceration and fistulation of the perianal tissue [1]. Lesions typically form a circular or semicircular pattern around the anus. The tissue may be thickened, red, and covered with discharge. The characteristic odor is often noticeable before the veterinarian even begins the examination. ### Rectal palpation A digital rectal examination allows the veterinarian to assess the extent of the disease inside the anal canal and rectum. It also helps identify any masses, thickening, or strictures. Rectal palpation is also critical for evaluating the anal sacs and detecting anal sac masses that could indicate adenocarcinoma. ### Ruling out anal sac adenocarcinoma Because anal sac adenocarcinoma can mimic perianal fistula, the veterinarian will carefully palpate the anal sacs and may recommend imaging such as radiographs or ultrasound, and possibly fine needle aspiration or biopsy of any mass. Blood work to check calcium levels is also relevant because anal sac adenocarcinoma can cause hypercalcemia. ### Staging the disease Lesion severity is graded using a visual analogue scale in clinical research [10]. In practice, veterinarians assess severity based on the depth of the lesions, the percentage of the anal circumference involved, and whether the fistulas have tunneled into deeper tissue. ### Colonic biopsy Because colitis is common in dogs with perianal fistula, and because clinical signs cannot reliably identify which dogs have it, colonic biopsies are recommended in all dogs presented with anal furunculosis [13]. This is typically performed during anesthesia. ## Severity Staging Table for Perianal Fistula in Dogs The following staging framework is based on clinical assessment of lesion depth and circumferential involvement. It is a practical guide for understanding disease severity and its implications for treatment. | Stage | Lesion Depth | Circumference Involved | Typical Clinical Picture | Treatment Implications | |--|--|--|--|--| | Mild | Superficial ulcers, no deep tunneling | Less than 25% of the anal circumference | One or a few small ulcers, mild discomfort, occasional licking | Good candidate for medical management alone. Topical tacrolimus may be appropriate for very limited disease [17]. | | Moderate | Ulcers extend into subcutaneous tissue, early fistula formation | 25% to 50% of the anal circumference | Multiple ulcers, noticeable odor, straining and vocalizing during defecation, licking | Cyclosporine is the first-line treatment [4]. Dietary modification may be added. Surgical resection of residual lesions may be needed if medical treatment does not fully resolve them. | | Severe | Deep fistulas, rectocutaneous tracts, involvement of deeper structures | More than 50% of the anal circumference | Extensive ulceration, severe pain, foul discharge, difficulty defecating, possible weight loss | Intensive medical management with cyclosporine, possibly combined with ketoconazole to reduce cost [18]. Surgery may be required for refractory disease [7]. Longer treatment duration and higher recurrence risk. | This staging is a clinical tool, not a formal laboratory test. Your veterinarian will assign a stage based on what they see and feel during the examination. ## Diagnostic and Treatment Decision Flow The following flowchart shows the main decision path from presentation to treatment. ```mermaid flowchart TD A[Owner notices perianal sores or straining] --> B[Veterinary examination] B --> C[Visual exam and rectal palpation] C --> D{Rule out anal sac adenocarcinoma} D -->|Mass found| E[Biopsy and staging of tumor] D -->|No mass| F[Diagnose perianal fistula] F --> G[Grade severity] G --> H{Severity stage} H -->|Mild| I[Topical tacrolimus or cyclosporine] H -->|Moderate| J[Cyclosporine first line] H -->|Severe| K[Cyclosporine plus adjunctive therapy] I --> L[Recheck in 4 weeks] J --> L K --> L L --> M{Response} M -->|Resolved| N[Maintain and monitor for recurrence] M -->|Residual or refractory| O[Consider surgery] ``` ## Treatment of Perianal Fistula in Dogs Treatment has two goals: resolve the active lesions and prevent recurrence. The approach depends on severity, response to initial therapy, and owner circumstances. ### Cyclosporine: First-Line Treatment Cyclosporine is recommended as the first-line treatment option for perianal fistula in dogs [4]. It is an immunosuppressive medication that specifically targets T cell activation, which addresses the underlying immune-mediated process. In a study of 26 dogs treated with cyclosporine, 69% experienced complete resolution, 27% improved but had residual lesions, and 4% showed no improvement [5]. The mean duration of treatment until resolution or no further improvement was 8.8 weeks, with a range of 4 to 24 weeks [5]. Recurrence occurred in 35% of dogs [5]. A separate study evaluated once-daily cyclosporine at different doses and found that the highest dose produced significantly better responses than lower doses [6]. The dogs improved most rapidly during the first five weeks of treatment [6]. Of the dogs that achieved remission, some relapsed after one, two, or six months [6]. Side effects are common. In one study, 58% of dogs developed side effects, most commonly increased coat turnover and transient vomiting, though none required treatment to be discontinued [5]. Another study reported similar side effects of increased coat turnover and transient vomiting [6]. ### Cyclosporine Combined with Ketoconazole Ketoconazole can be used to reduce the cost of cyclosporine treatment. Ketoconazole inhibits the liver enzymes that metabolize cyclosporine, which means lower doses of cyclosporine can achieve the same blood levels. A study of 16 dogs treated with ketoconazole and low-dose cyclosporine found that all dogs showed marked improvement in lesions and behavior within 14 days [18]. Thirteen dogs (93%) showed complete resolution during the 16-week treatment period [18]. Seven dogs (50%) had no recurrence after 12 months [18]. Recurrence occurred in three dogs at 8, 10, and 12 months after treatment, and in three dogs within one month of treatment [18]. The medication combination was well tolerated [18]. This combination is an important option for owners who are concerned about the cost of cyclosporine alone. ### Topical Tacrolimus Tacrolimus is a topical immunosuppressive medication that can be applied directly to the lesions. It is particularly useful for mild or localized disease, or as an adjunct to systemic treatment. A study of 10 dogs treated with topical tacrolimus ointment once to twice daily for 16 weeks found that full healing occurred in 50% of dogs and noticeable improvement occurred in 90% [17]. This makes tacrolimus a reasonable option for mild cases or for owners who want to avoid systemic medication. ### Dietary Modification Dietary modification is part of the treatment landscape for perianal fistula. An exclusive white fish and potato diet was used perioperatively in a surgical case series and was associated with a low rate of complications [15]. A study of German Shepherd Dogs with perianal fistulas and colitis found that treatment with immunosuppressive doses of prednisone and an alternative protein diet completely resolved fistulas in 33.3% of cases, improved them in another third, and left them unchanged in the final third [14]. Diet trials are typically used in combination with other treatments, not as sole therapy. The specific diet should be discussed with your veterinarian. ### Surgery for Refractory Cases Surgery is reserved for cases that do not respond adequately to medical management, or for residual lesions after medical treatment has achieved partial improvement [4]. The standard surgical approach is en bloc resection of diseased tissue with primary wound closure, combined with bilateral anal sacculectomy if the anal sacs have not already been removed [7]. In a retrospective study of 51 dogs treated with this technique, lesion recurrence occurred in 2%, fecal incontinence in 4%, and stricture formation in 13% [7]. A total of 94% of owners considered their dogs to have an acceptable level of fecal continence and an improved quality of life [7]. A separate study of 33 dogs treated with en bloc surgical excision and bilateral anal saculectomy, with perioperative administration of an exclusive white fish and potato diet, found that by one year after surgery, 87.9% of dogs had complete or near-complete resolution of visible fistula disease, and only 20.7% continued to have mild intermittent clinical signs [15]. Fecal incontinence was not reported in any dog, and complications were considerably less severe and less frequent than in previous reports [15]. ### Emerging Therapies Fluorescent light energy has been investigated as a treatment for perianal fistula. A preliminary study of four dogs treated with fluorescent light energy as sole management found that all dogs improved, with significant reductions in vocalization, straining, and licking after two weeks [19]. After five weeks, lesional areas had significantly decreased [19]. Only one dog required more than seven applications, and no adverse effects were reported [19]. This is an emerging option that may be appropriate for some cases. Mesenchymal stem cell therapy has also been investigated. A study of six dogs treated with intralesional injection of human embryonic stem cell-derived mesenchymal stem cells found that the treatment was well tolerated and that all six dogs were completely free of fistulas at three months postinjection [20]. However, at six months, two dogs had some fistula relapse [20]. This is an experimental approach, not a standard treatment. ### Why Antibiotics Alone Fail Antibiotics alone do not resolve perianal fistula because the disease is immune-mediated, not primarily infectious. Bacteria are secondary colonizers. While antibiotics may be used to manage secondary bacterial infection in the wounds, they do not address the underlying immune attack. A study of the humoral immune response in dogs with anal furunculosis found elevated antistaphylococcal IgG but normal antistaphylococcal IgA, a pattern consistent with secondary bacterial involvement rather than a primary staphylococcal disease [12]. ## Owner Decision Points Several key decisions will shape your dog's treatment journey. **Decision 1: How aggressively to treat initially.** Mild cases may respond to topical tacrolimus alone [17]. Moderate to severe cases typically require systemic cyclosporine [4]. Your veterinarian will recommend an approach based on severity and your dog's overall health. **Decision 2: Whether to use ketoconazole to reduce cyclosporine cost.** The combination of ketoconazole and low-dose cyclosporine is effective and can significantly reduce medication costs [18]. Discuss this option with your veterinarian. **Decision 3: When to consider surgery.** Surgery is typically considered when medical management fails to resolve the lesions or when residual lesions remain after partial improvement [4]. The decision involves weighing the risks of surgery, including the possibility of fecal incontinence and stricture formation, against the benefits of lesion resolution [7]. **Decision 4: How to manage diet.** Dietary modification may be part of the treatment plan. An exclusive white fish and potato diet has been used perioperatively in surgical cases [15], and an alternative protein diet was used in a study of dogs with concurrent colitis [14]. Discuss dietary options with your veterinarian. **Decision 5: How to monitor for recurrence.** Recurrence is common. In one study, 35% of dogs treated with cyclosporine experienced recurrence [5]. Regular follow-up examinations are essential to catch recurrence early. ## Monitoring and Follow-Up Cyclosporine treatment requires monitoring. Your veterinarian will likely recommend regular blood work to assess liver and kidney function, and to monitor cyclosporine levels if ketoconazole is used to reduce the dose [18]. The typical treatment duration is weeks to months. In one study, the mean duration of treatment until resolution or no further improvement was 8.8 weeks [5]. Dogs are typically rechecked after four weeks of treatment to assess response [10]. If the lesions have resolved, your veterinarian may recommend a maintenance dose or gradual tapering. If lesions persist, the dose may be adjusted or surgery may be recommended. ## Unsafe Home Remedies and Mistakes to Avoid **Do not treat with antibiotics alone.** Antibiotics do not address the immune-mediated cause of the disease and will not resolve the lesions. **Do not assume the condition is infectious.** Perianal fistula is not contagious to other pets or to people. It is an immune-mediated disease with a genetic basis [1][2]. **Do not delay veterinary care.** Perianal fistula is progressive. Early treatment produces better outcomes and may reduce the need for surgery. **Do not use over-the-counter creams or ointments without veterinary guidance.** Some products can worsen the condition or delay proper treatment. **Do not ignore signs of colitis.** Colitis is common in dogs with perianal fistula [13]. If your dog has diarrhea, mucus in the stool, or increased frequency of defecation, tell your veterinarian. ## Prevention Because perianal fistula has a strong genetic basis, prevention is limited. The disease is associated with specific genetic markers in German Shepherd Dogs [1][2]. If you are considering acquiring a German Shepherd Dog, be aware of the breed predisposition. There is no genetic test that can predict the disease with certainty. For dogs already diagnosed, the best prevention is consistent treatment and regular veterinary follow-up. Recurrence is common, and early detection of recurrent lesions allows for prompt treatment. ## Prognosis The prognosis for perianal fistula is guarded but manageable. Most dogs respond to medical treatment. In one study, cyclosporine resolved or reduced lesions in 96% of dogs [5]. However, recurrence is common, affecting 35% of dogs in that study [5]. For dogs that require surgery, the prognosis is also favorable. In one surgical case series, 94% of owners considered their dogs to have an acceptable level of fecal continence and an improved quality of life [7]. In another surgical series, 87.9% of dogs had complete or near-complete resolution of visible fistula disease by one year after surgery [15]. The disease is chronic. Many dogs require long-term management, and some require multiple courses of treatment. The goal of treatment is to control the disease and maintain a good quality of life, not necessarily to achieve a permanent cure. ## Limitations and When to Contact a Veterinarian This article provides general information about perianal fistula in dogs. Individual cases vary, and your veterinarian is the best source of advice for your dog's specific situation. Contact a veterinarian promptly if your dog has any of the following: - Open sores, ulcers, or draining tracts near the anus - A foul odor from the rear end - Straining, crying, or vocalizing during defecation - Excessive licking or biting at the rear end - Difficulty passing stool or passing thin, ribbon-like stool - Blood or pus in the stool or on the perianal skin - Weight loss or decreased appetite - Swelling or a mass near the anus - Increased thirst and urination, which can indicate hypercalcemia associated with anal sac adenocarcinoma These signs require veterinary evaluation. Do not attempt to treat perianal fistula at home. ## Frequently Asked Questions ### What causes anal fistula in dogs? Anal fistula in dogs is caused by an immune-mediated attack on the perianal tissues, not by an infection. The disease has a strong genetic basis, particularly in German Shepherd Dogs, and is associated with specific immune system genes [1][2]. ### Is perianal fistula in dogs contagious? No. Perianal fistula is not contagious to other dogs or to people. It is an immune-mediated disease with a genetic basis [1][2]. ### Can antibiotics cure perianal fistula in dogs? No. Antibiotics alone do not resolve perianal fistula because the disease is immune-mediated, not primarily infectious. Antibiotics may be used to manage secondary bacterial infection, but they do not address the underlying cause. ### What is the first-line treatment for perianal fistula in dogs? Cyclosporine is recommended as the first-line treatment option for perianal fistula in dogs [4]. It is an immunosuppressive medication that targets the underlying immune-mediated process. ### How long does treatment for perianal fistula in dogs take? Treatment duration varies. In one study, the mean duration of cyclosporine treatment until resolution or no further improvement was 8.8 weeks, with a range of 4 to 24 weeks [5]. Some dogs require longer treatment or maintenance therapy. ### Is surgery necessary for perianal fistula in dogs? Surgery is reserved for cases that do not respond adequately to medical management, or for residual lesions after medical treatment [4]. Many dogs can be managed with medication alone. ### What is the prognosis for a dog with perianal fistula? The prognosis is guarded but manageable. Most dogs respond to medical treatment, but recurrence is common [5]. Surgical treatment can produce good outcomes in refractory cases [7][15]. ### Can diet help a dog with perianal fistula? Dietary modification may be part of the treatment plan. An exclusive white fish and potato diet has been used perioperatively in surgical cases [15], and an alternative protein diet was used in a study of dogs with concurrent colitis [14]. Discuss dietary options with your veterinarian. ## Related Articles - [Anesthesia for Patients with Perianal Disease: Anal Sac and Mass Removal](/knowledge/veterinary-medicine/anesthesia-analgesia/anesthesia-patients-perianal-disease-anal-sac-mass-removal) - [Impacted Anal Glands In Dogs](/knowledge/veterinary-medicine/clinical-methods/impacted-anal-glands-in-dogs) - [How Do You Express Anal Glands On A Dog](/knowledge/veterinary-medicine/clinical-methods/how-do-you-express-anal-glands-on-a-dog) - [How To Express My Dogs Anal Glands](/knowledge/veterinary-medicine/clinical-methods/how-to-express-my-dogs-anal-glands) - [Dog Anal Glands Symptoms](/knowledge/veterinary-medicine/symptom-guides/dog-anal-glands-symptoms) - [How to Express Your Dog's Anal Glands at Home: When and How](/knowledge/veterinary-medicine/senior-and-chronic-care/express-dog-anal-glands-home) - [Cat Anal Gland Issues: Signs and Treatment](/knowledge/veterinary-medicine/digestive-and-urinary-care/cat-anal-gland-issues-signs-and-treatment) ## Sources 1. 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