What to use to poison lice and nits? - briefly
Apply a pediculicide formulated with permethrin 1% or pyrethrin plus piperonyl butoxide; for resistant infestations, use 0.5% malathion lotion or a dimethicone‑based product. Follow the label instructions precisely and repeat treatment after 7‑10 days to eliminate any surviving eggs.
What to use to poison lice and nits? - in detail
Effective agents for eradicating head‑lice infestations and their eggs fall into three categories: prescription neurotoxicants, over‑the‑counter (OTC) pediculicides, and non‑chemical alternatives. Each class works through a distinct mechanism, requires specific application procedures, and carries particular safety considerations.
Prescription neurotoxicants such as permethrin‑based creams (5 % concentration) and ivermectin oral tablets (200 µg/kg) target the nervous system of the insects, causing paralysis and death. Permethrin is applied to dry hair, left for 10 minutes, then rinsed; a second application after 7–10 days eliminates newly hatched nits. Ivermectin is taken orally as a single dose, with a repeat dose after one week if live lice persist. Both require physician authorization and are contraindicated for children under two years (permethrin) or under 15 kg (ivermectin).
OTC pediculicides include:
- 1 % pyrethrin‑piperonyl‑butoxide (PBO) lotions – rapid knock‑down, but resistance is common; repeat treatment in 7 days recommended.
- 1 % permethrin shampoos – similar to prescription formulation but lower concentration; apply to damp hair, leave 10 minutes, rinse; repeat after 7 days.
- Dimethicone‑based silicone oils (e.g., 4 % silicone lotion) – physically coat lice and nits, disabling respiration; leave on hair for 8–12 hours, then wash; repeat after 7 days.
- Spinosad 0.9 % suspension – insecticide with a novel mode of action; apply to dry hair, leave 10 minutes, rinse; repeat after 7 days.
Non‑chemical methods comprise:
- Heat treatment devices – calibrated combs or hair‑dryers delivering ≥50 °C for 10 seconds; effective against both adults and eggs when used correctly.
- Enzyme‑based products (e.g., malathion‑free formulations containing potassium permanganate) – degrade the protective coating of nits, facilitating removal; apply for 30 minutes, then comb out dead insects.
- Manual nit removal – fine‑toothed nit combs used on wet, conditioned hair; must be performed daily for at least 14 days to capture emerging lice.
Safety measures:
- Verify age and weight limits before applying any neurotoxicant.
- Perform a patch test for topical agents to detect hypersensitivity.
- Avoid simultaneous use of multiple chemical products to prevent additive toxicity.
- Wash all bedding, clothing, and personal items in hot water (≥60 °C) or seal them in plastic bags for two weeks to eliminate residual stages.
Monitoring:
- Inspect hair 48 hours after the first application; presence of live lice indicates treatment failure, possibly due to resistance.
- Conduct a thorough combing session every 2–3 days for two weeks to confirm eradication.
- Document any adverse reactions and consult a healthcare professional if symptoms persist.
By selecting an appropriate agent based on age, resistance patterns, and safety profile, and by adhering to the prescribed treatment schedule, complete elimination of head‑lice and their eggs can be achieved.