No abstract

Introduction Silicones (e.g., dimethicone) are effective and safe alternatives to insecticides for the treatment of head lice. However, silicones are lipophilic substances and do not only leave the hair greasy but they are also difficult to wash out. We have evaluated the efficacy and safety of a potential solution to this problem: an aqueous dispersion of a novel silylated polyol that has the same mode of action as dimethicone (suffocation) without its negative impact on hair characteristics. Methods This was a randomized, controlled, investigator-blinded, bicentric study that was conducted at two locations in the state of Florida (USA) to compare the test product (medical device) to a pyrethrum-based pediculicide that is a first-line, prescription-free treatment against head lice in the USA. The subjects ( n = 70) were randomly divided into two groups of 35 persons (test product group and reference product group), with each participant receiving two applications (day 0 and 7) of the product to be tested, according to the instructions for use. Efficacy and safety was evaluated at distinct time points. The primary objective was to establish a cure rate for the test product that was better than 70% at study end (day 10). Esthetic effects of the test product versus dimethicone were evaluated in a blinded, cross-over consumer study ( n = 100). Results At study end, the cure rate (corrected for re-infestation) of 88.2% with the test product significantly surpassed the pre-defined target of 70%, and thus the superiority of the test product versus the reference product was confirmed. The number of subjects cured (free of head lice) after the first treatment was remarkably higher with the test product than with the reference product (57.1 vs. 2.9%, respectively). Both products were safe and well tolerated and both showed beneficial esthetical effects. The consumer test demonstrated that the test product had better washing-out properties than dimethicone, as reflected by a significantly lower average rinsing time and number of washings required to restore the visual aspect of the hair, especially in terms of greasiness. Conclusion Aqueous dispersions of silylated polyols are a promising new class of pediculicides that combine high cure rates with optimal user convenience (short treatment period, easy wash-out with positive effect on hair quality). Trial Registration ClinicalTrials.gov identifier, NCT03617926. Funding Oystershell Laboratories.

Head lice are a public health issue, and resistance to available over-the-counter pediculicides is a concern. The objective of this randomized study was to evaluate the pediculicidal activity and safety of 1% Sodium Chloride spray (0.1709 M), (LiceFreee Spray ®) compared to the current recommended treatment for head lice with 1% Permethrin Crème Rinse. Forty-two subjects were randomized equally into Sodium Chloride or Permethrin group. Products were applied to hair according to the label instructions. After application of the products at Day 1 and Day 8, pediculicidal efficacy and safety were assessed at Day 1, Day 8 and Day 15. Second treatment was only applied on Day 8 to individuals with observed live lice using the same products and protocols as Day 1. Proportion of lice free subjects per group, the reduction in number of live lice per head and adverse effects were recorded after each visit. The results showed significantly higher pediculicidal activity for Sodium Chloride spray (85%) as compared to Permethrin (45%) at Day 15 (p < 0.05). Similar numbers of lice per head (21.76 range 10 to 68 versus 21.29 range 10 to 60 for Sodium Chloride and Permethrin groups, respectively) were observed for individuals at Day 1. At Day 15, lice per head infested reduced to 0.55 ± 1.50 in Sodium Chloride spray group compared to 5.45 ± 7.91 in the Permethrin group (p < 0.01). No serious adverse effects were observed in both groups. Sodium Chloride spray had superior efficacy to 1% Permethrin Crème Rinse in treating head lice and is a safe and excellent alternative to the current recommended treatment.

No abstract