Young1 reported recently that a 3.3% solution of podophyllotoxin in 90% alcohol had a marked fungicidal action upon hairs infected with Microsporum audouini. No growth was obtained after immersion of infected hairs for as little as one minute. He also reported 64% of cures after treatment of tinea capitis for six weeks with the concentration of podophyllotoxin mentioned above
I obtained podophyllotoxin from the same source2 as Young and prepared a 3.3% solution in 90% alcohol. I could not confirm its fungicidal activity in vitro. I obtained growth of M. audouini after immersing infected hairs not only for 1 minute but even for 15 minutes, one hour, and three hours. The procedure I followed was to place the infected hairs in the solution for the stated interval, rinse them with alcohol several times, and then transfer them to Sabouraud's culture medium. It is possible that Young may not