What can kill nits and lice? - briefly
Effective eradication requires FDA‑approved pediculicides such as 1 % permethrin or pyrethrin formulations, and, when resistance is suspected, prescription oral ivermectin or benzyl‑alcohol lotion. Complementary measures—hot‑water laundering of clothing and bedding and meticulous combing with a fine‑toothed nit comb—remove remaining eggs.
What can kill nits and lice? - in detail
Effective eradication of head‑lice infestations requires agents that destroy both the insects and their eggs. Chemical pediculicides, such as permethrin (1 %) and pyrethrin‑based shampoos, act on the nervous system of the lice, causing rapid paralysis and death. Dimethicone, a silicone‑based oil, suffocates the parasites and penetrates the egg shell, providing a non‑neurotoxic alternative. Malathion (0.5 %) and spinosad (0.9 %) are prescription‑only options that remain effective against strains resistant to pyrethroids.
Non‑chemical approaches complement topical treatments. Fine‑toothed nit combs, used on wet, conditioned hair, mechanically remove lice and nits; repeated combing at 2‑day intervals eliminates newly hatched insects. Heat devices that raise hair temperature to 50 °C for several minutes denature proteins in the parasites, achieving mortality without chemicals.
Environmental control limits re‑infestation. Washing clothing, bedding, and towels in hot water (≥ 60 °C) for at least 10 minutes, followed by drying on high heat, kills residual lice and eggs. Items that cannot be laundered should be sealed in airtight bags for two weeks, a period exceeding the lice life cycle. Vacuuming carpets and upholstered furniture removes detached insects and nits.
In summary, a comprehensive regimen combines an appropriate topical agent (permethrin, dimethicone, malathion, or spinosad), systematic nit combing, heat treatment if available, and rigorous laundering or isolation of personal items. This multi‑modal strategy ensures complete destruction of both adult lice and their unhatched eggs.