Top 7 Tips for Managing Chronic Anal Sac Disease

Nonneoplastic anal sac disease is a common concern among pet owners and clinicians; however, research on this topic is limited. Although disease usually occurs along a spectrum, starting with anal sac impaction that may progress to anal sacculitis or anal sac abscess in some cases (see Nonneoplastic Anal Sac Disease Terminology), anal sacculitis and anal sac abscesses can occur without history of anal sac impaction. Differentiation between anal sac impaction and anal sacculitis relies on subjective evaluation and is not clearly defined.¹ Recurrent anal sac problems warrant investigation into potential anal sacculitis or an underlying systemic condition.

Following are the author’s top 7 tips for managing patients with chronic anal sac problems.

1. Pain & Anxiety Relief

It is important to manage discomfort and prevent escalation of fear and/or anxiety because anal sac expression is often a recurrent procedure. Patients may benefit from anxiolytic and pain relief medication and should be evaluated on a case-by-case basis. Suggested medications include gabapentin (dogs, 10-20 mg/kg PO; cats, 50-200 mg/cat PO) for pain relief and mild sedation and trazodone (dogs, 5-10 mg/kg PO) or alprazolam (dogs, 0.02-0.1 mg/kg PO; cats, 0.5-1 mg/cat PO) for anxiety—alprazolam is a controlled medication, and state laws should be followed regarding dispensing controlled medications for pets.² These suggested medications can be continued for 1 to 2 days after anal sac expression, depending on the patient and amount of pressure used during expression. Injectable sedatives can be considered if oral medications administered prior to arrival at the clinic are not effective or owners are unwilling or unable to administer oral medications.

2. Physical Examination & Diagnostic Evaluation

If anal sac expression is required >2 to 3 times per year, a complete examination that includes CBC, serum chemistry profile, urinalysis, thyroid profile, and fecal flotation, as well as evaluation of diet and BCS, is recommended. Potential causes of recurrent anal sac disease include obesity, gastroenteritis, and decreased muscle tone.³

Allergy

Allergy may be the primary cause of or a contributing factor for anal sac disease. It is thus important during physical examination to look for subtle changes (eg, erythema or alopecia on the paws, erythema on the pinnae or inside the ear canals) owners may not observe in the home. Patients may be presented for signs of anal sac disease only, as owners typically focus on the odor and perceived mess associated with anal sac problems and overlook classic signs of allergy (eg, scratching, licking paws). In one study of patients with recurrent anal sac disease, atopic dermatitis was the most common comorbidity.⁴  

Patients with signs of allergic dermatitis should undergo an allergy workup, typically starting with an 8- to 10-week elimination diet trial. Treatment for environmental allergy can be initiated if response is not beneficial. Allergen-specific immunotherapy based on allergy testing is a safe and effective long-term treatment option. Other allergy treatment options include oral corticosteroids, oral cyclosporine, and oral oclacitinib. Reducing allergy triggered inflammation is the primary mechanism of allergy therapy for prevention of anal sac disease. Consequently, oclacitinib is usually least beneficial for long-term control due to its primary mechanisms of action, which are to block the sensation of itch via Janus kinase 1 and interleukin-31 inhibition. In addition, quality flea prevention is essential for all allergy patients, as flea bites can trigger a food or environmental allergy flare, even without presence of a flea allergy. Response to treatment should be based on behavior in the home and rectal examination with anal sac expression/palpation.

3. Anal Sac Secretions

Physical characteristics of anal sac secretions rarely help distinguish between anal sac impaction and anal sacculitis.⁵ A study evaluating anal sac material found no cytologic difference between healthy dogs and those with anal sac disease.⁶ Patient behavior in the home, gross examination of the perineum, ease of anal sac expression, characterization of the anal sac after expression, and gross appearance of anal sac secretions should be considered before selecting a therapy. The author does not recommend cytology of anal sac secretions as a major factor in treatment decisions.

4. Anal Sacculitis

Anal sacculitis occurs when inflammation develops in the anal sacs and results in thickening of the sac lining and duct. In addition to dragging and licking the perianal region, dogs with anal sacculitis may experience chronic leakage of hemorrhagic or purulent secretions from the anal sacs.⁶

5. Anal Sac Flushing

Anal sac flushing with the patient under sedation, followed by infusion of an antibiotic/antifungal/anti-inflammatory ointment without systemic antibiotic therapy, can be effective treatment for anal sacculitis but may need to be repeated every 2 weeks for 1 to 6 cycles.⁴ Combining systemic anti-inflammatory drugs and pain relief medication (eg, prednisone and gabapentin) with anal sac flushing can accelerate resolution and improve patient comfort.

6. Bacterial Culture

Bacterial culture and susceptibility can help manage anal sac abscesses. Samples should be collected from the draining tract after the perineum has been cleaned and before the tract has been flushed, helping avoid contamination. Only the draining tract should be swabbed.  

Culture of anal sac secretions in patients without an abscess is rarely useful because the anal sacs contain an array of bacteria.⁵

7. Alternative Options

Topical treatment can be considered in dogs that continue to drag and lick the perianal region after anal sacs have been expressed and underlying causes have been addressed. Anecdotally, some patients may benefit from therapy laser sessions focused over the anal sacs.  

Alternatively, 4% or 5% topical lidocaine cream applied to the perianal area can soothe irritation. Topical corticosteroids can also help manage pruritus and inflammation. Initially, 1% hydrocortisone can be applied every 12 hours for 7 to 10 days. If additional relief is needed, 0.025% triamcinolone cream can be applied every 24 hours for 7 to 10 days. Owners should be cautioned when using topical corticosteroids, as chronic application can cause local adverse effects (eg, alopecia, erythema, thinning of the skin, localized calcinosis cutis).  

Surgical removal of anal sacs is a viable treatment option. Complications (eg, fecal incontinence) can occur but are typically rare when the procedure is performed by an experienced surgeon.

Editor's note: A previous version of this article incorrectly noted oclacitinib's mechanism of action. This has been corrected as of April 19, 2023.