Although some people believe mayonnaise can kill head lice by smothering them, there is little clinical evidence of the effectiveness of this treatment, reports Mayo Clinic. Wet-combing, household cleaning and essential oils are also clinically unproven treatments.
Over-the-counter medications are available to treat lice. These medications usually contain pyrethrin and are usually applied to the hair after it has been washed. In certain cases, a doctor prescribes a stronger medication. Benzyl alcohol and malathion can only be prescribed to older children. The medicated shampoo Lindane is used as a last-resort treatment because of its severe side effects and is only approved for adult use, according to Mayo Clinic.