What should I do if lice shampoos are ineffective? - briefly
When an over‑the‑counter lice shampoo fails, switch to a prescription pediculicide (e.g., ivermectin or malathion) and perform thorough nit combing, repeating the treatment after 7–10 days. Additionally, launder all bedding, clothing, and personal items in hot water and vacuum the living area to eliminate residual eggs.
What should I do if lice shampoos are ineffective? - in detail
If over‑the‑counter lice‑killing shampoos do not eradicate the infestation, begin by verifying that the product was used according to the label: apply to dry hair, leave for the prescribed duration, and rinse thoroughly. Inadequate exposure time or insufficient coverage frequently allows surviving nits to hatch.
Next, adopt a systematic approach:
- Repeat the treatment – most shampoos require a second application 7–10 days after the first to kill newly emerged lice. Follow the exact timing recommended on the packaging.
- Combine with mechanical removal – use a fine‑toothed lice comb on wet, conditioned hair. Comb from scalp to tips, cleaning the comb after each pass. Perform this every 2–3 days for at least two weeks.
- Switch to a prescription option – oral ivermectin or topical permethrin 1 % (applied for 10 minutes) are more potent than many OTC formulas. A healthcare professional can prescribe these after confirming the diagnosis.
- Consider alternative OTC agents – products containing dimethicone, benzyl alcohol, or spinosad have demonstrated efficacy against resistant lice strains. Apply as directed and repeat the second dose if required.
- Treat the environment – wash all bedding, clothing, and personal items used within the previous 48 hours in hot water (≥ 130 °F) or seal them in a plastic bag for two weeks. Vacuum carpets and upholstered furniture; discard vacuum bags or clean filters afterward.
- Educate household members – ensure that all close contacts are examined and, if infested, treated simultaneously to prevent re‑infestation.
If lice persist after these measures, seek professional evaluation. Resistant populations may require combination therapy or a longer course of prescription medication. Documentation of treatment dates and outcomes assists clinicians in selecting the most effective regimen.