Antifungals for Tinea Corporis: When to Choose an Oral Agent

I enjoyed Dr Kirk Barber’s interesting Dermclinic quiz featuring a 5-year-old boy with a dramatic presentation of tinea corporis (CONSULTANT FOR PEDIATRICIANS, February 2009, page 43). I am curious to know why Dr Barber prescribed oral terbinafine for this patient. I was taught to reserve oral antifungals for the treatment of onychomycosis or tinea capitis but to use topical antifungals for other purposes.
-- Syed Rizvi, MD

In my experience, when tinea corporis is extensive, the best way to treat it is with a systemic agent. Otherwise, you often wind up “chasing” the infection from area to area and find it difficult to obtain a cure. In addition, in extensive tinea corporis, the hair follicles have likely been invaded, and much as in tinea capitis, topical therapy will not penetrate to the site of infection.
-- Kirk Barber, MD, FRCPC
Clinical Associate Professor of Medicine
and Community Health Sciences
University of Calgary
Alberta