Clinical efficacy of treatment for head lice - reply

EDITOR,--Both Manice Stallbaumer and colleagues and Ian F Burgess point out the potential or inevitable development of resistance to broadly used pediculicides, which makes extrapolation of results of studies performed in one country to another country hazardous. Indeed, since we completed our manuscript reports of resistance to permethrin have been published.1 2

We agree that a strategy for containing the pandemic of head lice should be based on the use of several active ingredients of proved efficacy. Hence we deplore …