Occlusive versus neurotoxic agents for topical treatment of head lice infestation: A systematic review and meta‐analysis

Abstract

Background Topical occlusive agents, such as petroleum jelly and silicone oils, kill head lice by coating and blocking its excretory system and are unlikely to induce treatment resistance. Although a popular alternative to neurotoxic pediculicides, their efficacy and safety remain unclear. Methods We searched CENTRAL, MEDLINE, HERDIN (from inception to October 31, 2017), and other relevant sources for randomized controlled trials that compared topical occlusive agents with neurotoxic pediculicides to treat patients with head lice infestation. Using Cochrane collaboration methods, we selected studies, assessed risk of bias, and pooled similar studies. We assessed certainty of evidence using GRADEPro. Results Seventeen trials (N = 2005) testing occlusive agents met inclusion criteria. Risk of bias was moderate across trials, mainly from lack of blinding of participants and personnel. As a class, occlusive agents may be more pediculicidal than neurotoxic agents (final cure rate, RR 1.20, 95% CI 1.02, 1.41; 16 RCTs, N = 1779; I2 = 88%; low certainty of evidence). Post hoc subgroup analysis suggests that this benefit may be limited to synthetic combination occlusive products. Adverse effects, such as skin and eye irritation, are similar between groups (RR 0.65, 95% CI 0.36, 1.17; 15 RCTs, N = 1790; I2 = 28%; low certainty of evidence). Conclusions In treating head louse infestation, evidence suggests occlusive agents may be superior to or equally efficacious as neurotoxic pediculicides. Adverse effects are few and minor. Future trials should use appropriate comparators and consider effects of confounders such as neurotoxin resistance. Additionally, optimal occlusive formulation and dosing regimen need to be determined.

Presence of the knockdown resistance (kdr) mutations in the head lice (Pediculus humanus capitis) collected from primary school children of Thailand

“…Consequently, instead of the contemporary scientific drug store pediculicides, traditional methods were the mainstay treatment to eliminate the louse. Folk remedies are based on the use of herb like custard apple leaves, plant-based herbal shampoo, occlusion techniques as well as anti-louse medical devices [33][34][35][36][37]. In urban areas, pediculosis cases are more properly managed with higher number of https://doi.org/10.1371/journal.pntd.0008955.g002 pediculicides prescription as they are more accessible at either over-the-counter pharmacy or dermatology clinic.…”

“…In some areas with a high prevalence of pediculosis, the treatment might better lean towards pediculicide-free treatment choices formultiple different reasons as follows; 1) Better safety profile 2) Greater availability in the locals and the advantages of no risk of developing resistant. These treatments include occlusive agents, herbal medicine, and anti-louse devices; heated air, suction, or electronic comb [33][34][35][36][37]. All of which pose no risk of resistance and have the advantages over pediculicides in terms of long term uses.…”

Paediatrics: how to manage pediculosis capitis

“… 98 – 104 A 2020 meta-analysis of 17 trials ( n =2005) showed that occlusive agents such as dimethicone may be superior or equally efficacious as neurotoxic pediculicides. 105 Dimethicone 4% lotion is non-toxic and not absorbed through the skin. As such, it has very few side effects.…”

Comparative efficacy and safety of interventions for treating head lice: a protocol for systematic review and network meta-analysis

“… 34 There is a 2019 systematic review that compared occlusive and neurotoxic head lice treatments as a group but not as individual treatments. 35 It has been many years since a comprehensive systematic review and meta-analysis has been performed comparing individual head lice treatments. 36 With Dodd review withdrawn and the review by Vander Stichele et al 25 years old, recent evidence on head lice treatment is clearly wanting.…”