How should lice be treated in children and adults? - briefly
Apply a 1 % permethrin or 0.5 % malathion lotion to dry hair, leave it for the indicated period, then comb meticulously to remove nits; repeat the application after 7–10 days to eliminate any newly hatched lice.
How should lice be treated in children and adults? - in detail
Effective control of head‑lice infestations requires a coordinated approach that addresses both the human host and the surrounding environment. The first step is to confirm the presence of live nits or adult insects through visual inspection of the scalp and hair shafts. Once confirmed, treatment proceeds as follows.
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Topical pediculicides – Over‑the‑counter products containing 1 % permethrin or 0.5 % pyrethrin with piperonyl butoxide are applied to dry hair, left for the recommended duration (usually 10 minutes), then rinsed. Resistance to these agents has been documented; in such cases, a prescription‑strength lotion with 0.5 % malathion or 0.05 % ivermectin may be used, following the specific label instructions for timing and repeat application after 7–10 days.
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Mechanical removal – A fine‑toothed nit comb, used on wet, conditioned hair, extracts nits and adult lice. The comb must be passed through each section of hair from scalp to tip at least twice per session, with sessions repeated every 2–3 days for a total of three to four times. This method can be employed alone for mild infestations or as an adjunct to chemical treatment.
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Oral therapy – Single‑dose ivermectin (200 µg/kg) may be prescribed for individuals who cannot tolerate topical agents or when topical resistance is suspected. Contraindications include pregnancy, lactation, and children weighing less than 15 kg.
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Environmental decontamination – Items that contact the head (combs, brushes, hats, pillowcases) should be soaked in hot water (≥ 50 °C) for at least 10 minutes or placed in a sealed bag for two weeks to kill dormant lice. Non‑washable fabrics may be sealed in plastic bags for the same period. Vacuuming carpets and upholstery reduces the risk of re‑infestation but is not a primary control measure.
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Follow‑up assessment – A second inspection should occur 7–10 days after the initial treatment to verify the absence of live lice. If any are found, repeat the chosen chemical or mechanical method according to the product’s guidelines.
Safety considerations differ by age. For children under two months, chemical agents are generally avoided; manual removal is the preferred strategy. For children older than six months, permethrin is considered safe when applied correctly. Adults may use the same regimens, with the addition that hair‑type considerations (e.g., thick or curly hair) may necessitate more thorough combing.
Adhering to the outlined protocol—accurate diagnosis, appropriate chemical or mechanical intervention, environmental hygiene, and scheduled re‑evaluation—provides reliable eradication of head‑lice infestations across all age groups.