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PEER REVIEWED 52 CE: CANINE ATOPIC DERMATITIS Oral and Topical Glucocorticoids Glucocorticoids are fast-acting medications that deactivate many inflammatory cells and reduce inflammatory/itch mediators. They are used for both inducing remission and maintaining long-term control in CAD. Unfortunately, prolonged systemic use is associated with polyuria, polydipsia, polyphagia, muscle and skin atrophy, bacterial and fungal infections, demodicosis, and iatrogenic hyperadrenocorticism. 1,29-31 Topical steroids are the mainstay of therapy for bringing localized CAD skin lesions under remission; medium-potency glucocorticoid sprays, such as triamcinolone acetonide (Genesis, us.virbac.com ) and a diester hydrocortisone aceponate (Cortavance, us.virbac.com ), show high efficacy in CAD. 3 The triamcinolone acetonide and hydrocortisone aceponate sprays are currently unavailable in the United States; however, another highly potent diester steroid, mometasone furoate, is available as a cream through pharmacies and is widely used in my practice. As suggested for human atopic dermatitis, daily application of steroids for 2 to 4 weeks to clear localized skin lesions should be followed with the intermittent use of the same product (eg, 2 to 3 times per week) on the previously affected skin even if visible lesions have disappeared. This "proactive treatment" approach reduces the risk for flares and extends the time of remission in humans 32 and dogs 33,34 compared with reactive therapy (ie, therapy only when clinical signs are visible). Even though mometasone furoate and hydrocortisone aceponate induce mild dermal degradation through inhibition of collagen I and III propeptides, no visible skin atrophy has been observed in CAD skin lesions during long-term intermittent topical application. 33-35 If CAD signs are too extensive to be controlled with only topical formulations, then short-acting oral glucocorticoids are recommended in conjunction with topical steroids. 3 Prednisone/prednisolone (0.5 to- 1 mg/kg PO) or methylprednisolone (0.4 to- 0.8 mg/kg PO) should be administered q24h or divided into 2 doses for 5 to 15 days, then reduced or discontinued as signs decrease based on patient response. To reduce the adverse effects and dose of oral glucocorticoids in some allergic dogs, the glucocorticoid-antihistamine combination Temaril-P (trimeprazine 5 mg/prednisolone 2 mg, zoetis.com ) can be effectively used; the antihistamine trimeprazine seems to potentiate the low dose of prednisolone, achieving a steroid-sparing effect. 36 TABLE 1 Highly Effective Drugs for Remission and Management of Canine Atopic Dermatitis INDUCING REMISSION: "GET CONTROL" LONG-TERM MANAGEMENT: "KEEP CONTROL" Oral and/or topical glucocorticoids Oral and/or topical glucocorticoids Oclacitinib Cyclosporine Lokivetmab Lokivetmab Surgery Oclacitinib BOX 6 Improving Epidermal Barrier Dysfunction The complex process of epidermal differentiation is disturbed in CAD lesions, and the impaired skin barrier offers potential targets for therapeutic intervention, such as fatty acids (oral supplements or topical solutions) and various topical treatments. Weekly bathing with a mild nonirritating shampoo and postbathing topical moisturizers are recommended for each patient; this therapy provides a direct soothing effect to the skin, physically removes surface allergens, and increases skin hydration. 1,5 According to the systematic review of clinical trials, essential fatty acid supplementation is indicated only for long-term management of CAD as an adjunctive treatment; the clinical benefit of essential fatty acid supplements on the skin may take up to 2 months to be seen. 1,5 In recent years, some topical (spot-on, spray, shampoo, emulsion) formulations containing fatty acids and ceramides have been introduced for dogs with CAD; however, their efficacy is inconsistent, and veterinarians should weigh their benefit and cost before pdeciding to use them. 5