New head lice product trials show strong anti-lice activity

A recent publication focussing on novel potential physically-acting anti-lice treatments has identified the surfactant 1,2-octanediol as an effective pediculicide in both in vitro and in vivo studies.

The study by Burgess et al., published on 16 April 2012 in PLoSone, discusses both in vitro assessment of several different surfactant molecules and several randomly-controlled trials (RCT) of different formulations of the active ingredient.

The study first assessed several surfactant molecules for effective pediculicide activity. These molecules all possessed one or more alcohol groups. The study found molecules with two adjacent alcohol groups (diols) to be the most effective overall. Although 1,2-decanediol was shown to be the most effective diol pediculicide, the smaller 1,2-octanediol was preferred for further testing due to its faster method of acting, in that it worked quickly enough to prevent egg laying.

RCTs using two applications over a two-week period found that a 5% 1,2-octanediol solution was more effective at removing lice infections than a 0.5% malathion solution. For a 2–2.5 h treatment the 1,2-octanediol showed a cure in 71% of cases, compared to 47% of cases for malathion. The cure rate increased to 88% for an 8h 1,2-octanediol exposure (n = ~170 in each group).

A further study was made using different carrier fluids for the 1,2-octanediol. It was found that an alcohol-free mousse (8h treatment) was as effective as the 2 h treatment of the alcohol solution, curing roughly 78% of participants (n = 35).

The authors conclude that 1,2-octanediol is an effective pediculicide with few adverse effects. It is thought to work by disrupting the outer lipid coating of lice, ensuring death by water loss. Full results, statistical analysis and supporting information can be found using the link above.