Treatment of head lice

The standard pharmaceutical agents for head-lice eradication are lindane (1%) (gamma benzene hexachloride), permethrin (1%), and malathion (0-5%). After recent arguments for resistance against pediculicides,2-4 wet-combing with a fine-toothed comb was recommended as first-line treatment for pediculosis by the UK Department of Health in 1996.5 Wet-- combing has been assessed when used in combination with pediculicides6,7 but not when used alone. However, today's Lancet carries a report by R J Roberts and colleagues of a comparison of a commercial wet-- combing kit against malathion. Parents were asked to treat children with head lice chemically or physically with a comb. The combing procedure was complex, involving several types of comb and repeat treatments every 3-4 days for 2-3 weeks, whereas, malathion was given in only two doses, a week apart. Fewer patients in the combing group demonstrated cure than in the malathion group. Some patients in both groups had recently used a pediculicide before entering the study, which may have influenced the results in favour of malathion. However, even after this pretreatment was taken into account, cure rates were still higher in the malathion group. The finding in this study thus indicates that policies based on wet combing may not be justified without further data from clinical trials.