Comparative Efficacy of Vinegar Before and After using Permethrin Shampoo for Removal of Head Lice in the Elementary School Students

Background and Aim: Nowadays, there are many challenges in the treatment of head lice infestation and the efficacy of anti-lice products is a very important factor. The aim of this study was to determine the effectiveness of using vinegar before and after application of permethrin shampoo for the treatment of head lice infestation in the elementary school students in Qom Province. Materials and Methods: Our study inclueded 200 female students infested with head lice referring to two comprehensive urban health centers of Qom University of Medical Sciences from September to February 2020. The patients were between 13 and 17 years of age. Using blocked randomization with randomly selected block sizes, the patients were treated with either application of vinegar before or after using 1% permethrin shampoo. Removal of adult human head lice, nymphs, and nits were considered as the outcome of the treatment methods. Results: The current standard treatment method proposed by the Ministry of Health (use of vinegar after applying permethrin shampoo 1%) resulted in the treatment of the infestation in 45% of cases. But the experimental treatment method (using vinegar before applying permethrin shampoo 1%) led to successful treatment of 79% of the participants and showed a high Odds Ratio (OR = 4.6 CI = 2.5-8.5 p = .000). Conclusion: This study did not approve the current standard treatment method of the Ministry of Health (use of vinegar after consuming permethrin shampoo 1% for removal of head lice infestation). Therefore, we recommend application of vinegar before using permethrin shampoo 1%.