In this issue of JAMA Dermatology, Mikailov et al1 challenge our propensity to automatically order costly confirmatory diagnostic testing before initiating systemic therapy with terbinafine hydrochloride for onychomycosis. There are 2 issues of importance here: safety and cost-effectiveness.
The issue of cost-effectiveness is relatively straightforward now that the price of generic terbinafine for an entire treatment course has fallen from $547 to $10. Mikailov et al1 have shown that it is more cost-effective to treat every presumptive case of onychomycosis with oral terbinafine rather than prove that the abnormality of the toenail is in fact due to onychomycosis.
Kanzler MH. Reevaluating the Need for Laboratory Testing in the Treatment of OnychomycosisSafety and Cost-effectiveness Considerations. JAMA Dermatol. 2016;152(3):263-264. doi:10.1001/jamadermatol.2015.4203