How many times should the head be washed to treat lice? - briefly
A single thorough wash with an approved lice‑killing shampoo, followed by a repeat wash after 7–10 days, effectively eradicates the infestation. Further washes are unnecessary unless a new infestation is confirmed.
How many times should the head be washed to treat lice? - in detail
Effective lice eradication requires a defined washing schedule combined with appropriate treatment agents. The adult louse survives for about five days, while eggs (nits) hatch after 7‑10 days; therefore, a single wash cannot eliminate the entire population.
The standard protocol includes:
- First wash with a pediculicide shampoo or lotion, applied according to product directions and left on the scalp for the recommended time.
- Second wash 7–10 days after the initial treatment, targeting newly emerged lice that survived the first application.
- Optional third wash 14 days after the first, employed only if live lice are still observed.
Repeating the wash within the 7‑10‑day window aligns with the hatching period of nits, ensuring that any newly emerged insects are removed before they reproduce. Additional measures such as combing with a fine-toothed lice comb, laundering bedding at high temperature, and vacuuming furniture support the chemical treatment and reduce reinfestation risk.