A recent review on head lice treatments available in the United States described a marked decline in the effectiveness of permethrin/synergized pyrethrins (collectively pyrethroids), likely due to resistance arising from widespread and indiscriminate use over 30 years.
The review also noted that the potential toxicity of lindane, and the availability of safer and more effective alternatives, should limit its use. Prescription products that are safe and effective include malathion, benzyl alcohol, spinosad, and topical ivermectin.
Home remedies such as petroleum jelly, mayonnaise, and essential oils, have not been demonstrated as safe or effective and may cause adverse reactions.