What is the recommended treatment for head lice?

Head Lice Treatment Recommendations

Permethrin 1% cream rinse is the first-line treatment for head lice, applied to affected areas and washed off after 10 minutes, with re-treatment in 7-10 days if live lice are still present. 1

First-Line Treatment Options

1. Permethrin 1% cream rinse
   • Apply to affected areas and wash off after 10 minutes
   • Re-treat in 7-10 days if live lice are still present
   • Safe for pregnant and breastfeeding women
   • Possible side effects include pruritus, erythema, and edema 1

Alternative Treatment Options

If permethrin treatment fails despite correct application, consider these alternatives:

1. Pyrethrins with piperonyl butoxide

   • Apply to dry hair, leave on for 10 minutes, then wash off thoroughly
   • Re-treat in 7-10 days if live lice are still seen
   • Safe for pregnant and breastfeeding women 1

2. Malathion 0.5% lotion (for children ≥24 months)

   • Apply to dry hair, leave on for 8-12 hours, then wash off thoroughly
   • Pay particular attention to the back of head and neck during application
   • CAUTION: Highly flammable - avoid open flames, electric heat sources, and smoking
   • Do not use in children under 24 months 1, 2

3. Ivermectin (for children weighing >15 kg)

   • Oral administration of 250μg/kg repeated in 2 weeks
   • Limited ovicidal activity
   • Do not use in children weighing less than 15 kg 1

4. Benzyl alcohol 5% (for children ≥6 months)

   • Apply for 10 minutes and repeat in 7 days
   • Not ovicidal 1

Non-Pharmacological Interventions

To prevent re-infestation:

• Machine wash clothing, bedding, and towels in hot water and dry on high heat cycle for at least 20 minutes
• Soak combs and brushes in hot water (>130°F) for 5-10 minutes
• Items that cannot be washed should be removed from body contact for at least 72 hours
• Use a fine-toothed (nit) comb to remove dead lice and eggs after treatment 1

Special Populations Considerations

• Children under 2 years: Avoid lindane
• Children under 24 months: Avoid malathion
• Pregnant/breastfeeding women: Use permethrin or pyrethrins with piperonyl butoxide 1

Follow-Up and Re-Treatment

1. Evaluate patients after 1 week if symptoms persist
2. Re-treat if live lice are found
3. Consider switching to an alternative regimen if initial treatment fails despite correct application 1

Important Caveats

• School attendance: No healthy child should be excluded from school because of head lice. "No-nit" policies for return to school should be abandoned as head lice do not pose significant health risks 1, 3

• Misdiagnosis risk: Misdiagnosis of lice infestations is common and contributes to pediculicide resistance through overuse. Only use treatments if live lice or viable nits are discovered 3

• Malathion application time: While the FDA label recommends 8-12 hours application time for malathion, research suggests that a shorter application time (30 minutes) may be sufficient to kill lice while reducing transdermal absorption 2, 4

• Resistance concerns: Resistance to pyrethroids and lindane has been documented, but malathion has not shown significant resistance patterns in the United States 3

• Nit removal: After treatment, use a fine-toothed comb to remove nits. Formulations containing 5% acetic acid or 8% formic acid, as well as acid shampoos and conditioners, can help with nit removal 5