Treat head lice effectively with over-the-counter options like permethrin 1% lotion or pyrethrins with piperonyl butoxide, applied to the scalp for 10 minutes and rinsed, with a repeat treatment in 7–10 days. For resistant cases, prescription options such as ivermectin 0.5% lotion, malathion 0.5% lotion, or oral ivermectin may be necessary. Ensure thorough application and follow-up to eradicate lice and nits.
January 10, 2025

Getting Rid of Head Lice

Evidence-Based Over-the-Counter Guide

William Shen

William Shen

Co-founder & CPO

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Head lice are parasitic insects that infest the scalp and hair, causing itching and discomfort. Treatment aims to eliminate live lice and eggs (nits).

First-line recommendations:

  • Permethrin 1% lotion/cream rinse: Applied to the scalp and hair for 10 minutes, then rinsed. Repeat in 7–10 days to ensure eradication. Nix Lice Killing Creme Rinse (FDA NDA 019918).

  • Pyrethrins with piperonyl butoxide: Pyrethrins 0.3% with piperonyl butoxide 4% applied to the affected area, then rinsed off with water after 10 minutes. Rid Lice Killing Shampoo (FDA M031).

Prescription medications:

  • Ivermectin 0.5% lotion: Applied to dry hair and left for 10 minutes. Kills live lice and newly hatched lice without requiring combing.

  • Malathion 0.5% lotion: Applied for 8–12 hours before washing off. Recommended for resistant cases. Recommended product.

  • Oral ivermectin: Single-dose oral therapy for resistant cases.

Citations:

Kimberlin DW. Red Book: 2024-2027 Report of the Committee on Infectious Diseases, 33rd Edition. American Academy of Pediatrics; 2024

Gunning K, Kiraly B, Pippitt K. Lice and Scabies: Treatment Update. Am Fam Physician. 2019; 99(10): p.635-642. pmid: 31083883.

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