How to Treat Pruritus

Updated September 2025 by Elizabeth Layne, DVM, DACVD; BluePearl Pet Hospital, Midvale, Utah; Montana Veterinary Dermatology, Bozeman, Montana; Unleashed Veterinary Dermatology, Stratford, Connecticut

Pruritus has many causes (fungal, bacterial, ectoparasites, food allergy, atopic dermatitis; less commonly autoimmune, paraneoplastic, metabolic) in cats and dogs. A general understanding of these causes can help in identification of specific etiology and treatment options for individual patients.

Clinical Signs & Diagnosis

Patient history and physical examination results can help narrow the differentials (see Characteristics of Pruritus Based on Cause). Age and nature of onset can be helpful. Although parasitic infection or food allergy can occur at any age, atopic dermatitis is common in young dogs and does not usually begin in dogs older than 3 to 4 years of age. Atopic skin syndrome typically occurs in younger cats, although the reported age of onset ranges from 6 months to 15 years.¹ Evidence of contagion suggests parasitic infestation or dermatophytosis (especially in cats). Concomitant GI signs may indicate food allergy. Systemic illness, advanced age, and hematologic or clinicopathologic abnormalities can indicate autoimmune, paraneoplastic, or metabolic causes of pruritus.

Basic in-clinic diagnostic procedures (eg, skin scrapings, skin cytology) can help rule out common and obvious causes. Fleas and Cheyletiella spp mites can be identified by brushing or combing the hair coat. Superficial scrapings, deep scrapings, or hair pluckings are required when looking for mites. Samples from lesions should be obtained via impression smear and tape preparation to screen for staphylococcal, Malassezia spp, and dermatophytic infections.

Diagnostic Criteria for Canine Atopic Dermatitis

Atopic dermatitis is highly likely if 5 or more of the following 8 criteria are confirmed and other differentials have been ruled out.²

1. Age of onset <3 years

2. Patient lives mostly indoors

3. Corticosteroid-responsive pruritus

4. Front paws affected

5. Ear pinnae affected

6. Ear margins affected

7. Dorsal lumbosacral area unaffected

8. Chronic or recurrent yeast infection

Diagnostic Criteria for Feline Atopic Skin Syndrome

Nonflea hypersensitivity dermatitis (atopic skin syndrome or food allergy) is likely if 6 or more of the following 10 criteria are confirmed and flea allergy has been ruled out. An elimination diet trial is necessary to rule out food allergy.¹

1. Pruritus at onset

2. At least 2 of the following classical clinical reaction patterns

   1. Symmetrical alopecia

   2. Miliary dermatitis

   3. Eosinophilic dermatitis

   4. Head and neck erosions/ulcerations

3. At least 2 sites affected

4. Miliary dermatitis as a dominant pattern

5. Eosinophilic dermatitis, symmetrical alopecia, or erosions/ulcerations on the head, face, lips, ears, or neck

6. Nonsymmetrical alopecia on the lumbosacral area, tail, or pelvic limbs

7. Symmetrical alopecia on the abdomen

8. Absence of erosions/ulcerations on the thoracic limbs

9. Absence of lesions on the sternum or axilla

10. Absence of nodules or tumors

Treatment for Pruritus

Cause-Specific Treatment

• For identified bacterial and/or yeast infection, appropriate treatment without corticosteroids should be provided, and antimicrobial stewardship principles should be considered. Topical antiseptic therapy and first-choice systemic antibiotics (if necessary) should be prioritized.³

• For moist, greasy, odiferous dermatitis with pronounced pruritus, treatment for yeast infection should be considered, even if not found on cytology.

• If parasites are identified, treatment should be provided accordingly.

• Scabies mites can be difficult to find; empiric treatment is needed when scabies is suspected even if mites are not seen on skin scraping.

• Flea allergy dermatitis can be present without evidence of fleas; all dogs and cats that come into contact with the patient should receive routine flea prevention whether or not fleas are found.

Short-Term Antipruritic Treatment If No Cause or Infection Is Determined

• Glucocorticoids (systemic or topical), oclacitinib (dogs only), and ilunocitinib (dogs only) are rapid-acting and effective for immediate use.⁴

• Cyclosporine may take several weeks to be effective, making this drug less desirable for quick, short-term relief.

• Lokivetmab (dogs only) can be considered for uninfected allergic pruritus.

• Antihistamines are not typically effective.

Medicated Shampoo

• Before a shampoo is prescribed, confirmation is needed that the pet owner is able and willing to bathe the patient.

• Patients with superficial infections should be bathed twice per week for 4 weeks or until cytology is negative.

• Antiseptic shampoo (eg, chlorhexidine with miconazole)

  • If bacteria and/or yeast are found on cytology

  • Single active-ingredient shampoos (eg, chlorhexidine, miconazole) may be used if only bacteria or only yeast are found on cytology, but this occurs less commonly

  • Weekly bathing may be necessary long-term in dogs prone to microbial overgrowth.

• Antipruritic/barrier repair shampoo (eg, colloidal oatmeal, ceramides, sphingolipids)

  • May be considered if cytology is negative for bacteria and/or yeast

  • Weekly bathing is reasonable for dogs without infections.

Two-Week Recheck (If Necessary)

• At the recheck, what has and has not improved should be determined (skin lesions versus pruritus level).

• Uncomplicated parasitic or infectious causes should improve, and further action may not be necessary.

• Treatment of secondary infection often provides a clearer picture of underlying disease. If pruritus is controlled with treatment for infection, nonallergic primary causes of skin infections (eg, hypothyroidism, sebaceous adenitis) can be considered.

• An elimination diet trial can be considered if indicated.

• If substantial lesions are still present, repeat cytology and bacterial culture and antimicrobial susceptibility testing or skin biopsy are needed.

Long-Term Management Plan for Chronic Conditions

• Multiple therapies should be combined to provide effective relief that is affordable and convenient for the owner while potential adverse effects are minimized.

• For food allergy, lifelong dietary restriction should be emphasized.

• For atopic dermatitis/atopic skin syndrome, allergy testing for immunotherapy formulation (with allergen-specific injections or sublingual drops) should be considered and additional long-term management should be implemented.

  • Medication with cyclosporine (dogs, cats), oclacitinib (dogs only), ilunocitinib (dogs only), or lokivetmab (dogs only)

  • Medication with a topical or systemic corticosteroid if necessary

  • Frequent bathing with appropriate antiseptic or cleansing shampoo

  • Epidermal barrier support, including oral and topical fatty-acid supplementation, topical ceramides, and phytosphingosine