How should lice be treated? - briefly
Lice infestations are managed with a single application of a 1 % permethrin or pyrethrin‑based shampoo or lotion, followed by thorough combing of wet hair with a fine‑toothed nit comb, and a repeat treatment after 7–10 days to eliminate any newly hatched nits. For resistant cases, prescription options such as ivermectin, benzyl‑alcohol lotion, or malathion may be used, and all bedding, clothing, and personal items should be washed in hot water or sealed for two weeks.
How should lice be treated? - in detail
Effective management of head‑lice infestations requires a systematic approach that combines accurate diagnosis, appropriate therapeutic agents, mechanical removal, and preventive measures.
First, confirm the presence of live lice or viable nits attached within ¼ inch of the scalp. Use a fine‑toothed comb on damp hair to separate strands and expose any insects. Detection of live adults, nymphs, or viable eggs confirms the need for treatment.
Second, apply a proven pediculicide. Options include:
- Permethrin 1 % lotion – applied to dry hair, left for 10 minutes, then rinsed; a second application after 7 days eliminates newly hatched lice.
- Pyrethrin‑based products – combined with piperonyl‑butoxide to enhance efficacy; follow manufacturer instructions regarding exposure time.
- Spinosad 0.9 % suspension – single application, no repeat required for most cases.
- Ivermectin 0.5 % lotion – applied for 10 minutes, safe for children over 6 months; a repeat dose after 7 days may be necessary.
Third, conduct mechanical removal. After chemical treatment, use a fine‑toothed nit comb at least twice daily for 10 days. Wet the hair, apply a conditioner to reduce friction, and systematically comb from scalp to ends, removing each egg and adult. Dispose of combed material in sealed plastic bags.
Fourth, address resistant infestations. If lice survive after two standard treatments, consider:
- Dimethicone 4 % lotion – a silicone‑based product that suffocates insects without neurotoxic action.
- Malathion 0.5 % lotion – reserved for highly resistant cases; avoid use on children under 6 years.
- Prescription oral ivermectin – a single dose of 200 µg/kg, repeated after one week, for severe or refractory cases.
Fifth, implement preventive strategies. Wash bedding, hats, and personal items in hot water (≥ 130 °F) or seal them in plastic bags for two weeks. Encourage regular head‑checking in schools and households, especially after known outbreaks. Avoid sharing combs, brushes, or headgear.
Finally, schedule a follow‑up examination 10–14 days after the initial treatment to verify eradication. Absence of live lice and viable nits confirms success; otherwise, repeat the chosen regimen or switch to an alternative agent.
By adhering to this protocol—diagnosis, appropriate chemical therapy, diligent combing, resistance management, and prevention—head‑lice infestations can be eliminated efficiently and with minimal risk of recurrence.