What works best against lice and nits? - briefly
The most reliable approach combines a prescription pediculicide—such as 1 % permethrin or 0.5 % malathion—applied according to label directions, with thorough nit removal using a fine‑toothed comb. A second treatment 7–10 days later eliminates any newly hatched lice and prevents re‑infestation.
What works best against lice and nits? - in detail
Effective eradication of head lice and their eggs requires a combination of chemical, mechanical, and environmental strategies.
First‑line chemical agents include over‑the‑counter products containing 1 % permethrin or 0.5 % pyrethrin. These formulations must remain on the scalp for the recommended duration (usually 10 minutes) before rinsing. When resistance is suspected, prescription‑strength options such as 0.5 % malathion, 0.05 % ivermectin lotion, or 0.025 % spinosad provide higher efficacy. All treatments should be applied to dry hair, ensuring complete coverage from scalp to tips, and left undisturbed for the full contact time.
Mechanical removal complements topical therapy. A fine‑toothed nit comb, preferably metal with teeth spaced 0.2 mm apart, extracts live insects and unhatched eggs. The comb should be used on wet, conditioned hair, progressing from scalp outward in systematic passes. Repeating the combing session every 2–3 days for a total of three cycles eliminates newly hatched nymphs that survive the initial chemical exposure.
Silicone‑based lotions (e.g., dimethicone 4 %) act by suffocating lice and loosening the cement that secures nits to hair shafts. Application involves saturating the hair, covering with a plastic cap for 8–10 hours, then washing and combing. Studies show comparable cure rates to traditional insecticides with reduced risk of resistance.
Adjunctive measures address reinfestation risk. Immediate washing of bedding, hats, and clothing in hot water (≥ 60 °C) or sealing items in airtight bags for two weeks prevents egg hatching. Vacuuming upholstered furniture and car seats removes detached lice. Personal items such as combs, brushes, and hair accessories should be immersed in hot water (≥ 55 °C) for 10 minutes.
The recommended protocol is:
- Apply a suitable pediculicide (permethrin, malathion, ivermectin, or spinosad) according to label instructions.
- After drying, comb hair with a nit comb, removing all visible insects and eggs.
- Repeat the chemical treatment after 7 days to target any surviving hatchlings.
- Perform combing sessions on days 2, 5, and 9 post‑treatment.
- Process all personal textiles and environmental surfaces as described.
Adherence to this multi‑modal regimen yields cure rates above 90 % in controlled trials, minimizing recurrence and limiting the spread of resistant lice populations.