Podophyllin, a resin derived from the May apple ( Podophyllum peltatum Linné ), contains the active agent podophyllotoxin, which is a cytotoxic agent that arrests mitosis in metaphase. It is a physician-applied medicine used in the treatment of external genital warts and condyloma acuminatum. It can be applied weekly for up to 6 weeks. Warts visible after 6 treatments usually do not respond to further therapy.