To the Editor We applaud the important research findings by Patel et al1 regarding pediatric onychomycosis. In this study, the authors appropriately conclude that routine laboratory monitoring of children during treatment with terbinafine may be unnecessary, considering (1) the low incidence of clinically significant adverse effects; (2) the costs of laboratory tests; (3) workup of spurious laboratory abnormalities; and (4) patient discomfort.