Which Topical Glucocorticoids Should Be Used?

The antiinflammatory potency of topical glucocorticoids varies widely (Table 109-1 and Figure 109-1). Lotions and gels are easier and less messy to apply and dry quickly, leaving fewer residues. Oils, creams, and ointments may moisten and soothe dry and inflamed skin but can be occlusive and are contraindicated for use in exudative or seborrheic ears.

The topical glucocorticoids incorporated in most polyvalent ear medications are appropriate for managing the mild to moderate inflammation in acute otitis externa. Use of antimicrobial-containing products, however, is not indicated in the absence of infection.

A variety of glucocorticoid-containing eyedrops, eardrops, and ear cleaners are available, although some of these are human products not licensed for use in animals. Soluble glucocorticoid preparations also can be added to tromethamine/ethylenediaminetetraacetic acid (Tris-EDTA) solutions or compounded with sterile saline to create solutions with an appropriate glucocorticoid concentration (e.g., 0.02% to 0.1% dexamethasone).

Mild inflammation responds rapidly to low-potency topical glucocorticoids, but progressively more severe inflammation requires longer courses of more potent products. Fluocinolone acetonide in 60% dimethylsulfoxide (DMSO) is particularly effective at reducing tissue hyperplasia.

Products should be applied once or twice daily until remission occurs; efficacy may be greater with more frequent administration, but compliance with treatment may be lower. Once the otitis has resolved, topical glucocorticoids should be used at the lowest frequency that controls the inflammation or discontinued if possible. When continued use is required, data on owner compliance from studies of atopic dermatitis and recurrent pyoderma suggest that a regimen of treatment on 2 or 3 consecutive days each week (i.e., “weekend therapy”) is better adhered to than therapy every other day or twice weekly (Carlotti et al, 2004; Martins et al, 2012).