Table of Contents
Overview
Head lice are tiny, parasitic insects that feed on human blood and live on the scalp. They can spread quickly through direct contact, such as sharing combs, hats, and other personal items. Head lice infestations, while uncomfortable, are usually not serious and can be cleared up with over-the-counter or prescription treatments.
Treatments
Treating head lice requires repeated applications of medication to ensure all lice and eggs (nits) are killed. Over-the-counter treatments typically contain an insecticide called permethrin, which kills adult lice and some eggs. Prescription treatments, such as ivermectin, may be needed for more resistant lice or for people who cannot tolerate permethrin.
In addition, medicated shampoos or lotions, such as NIX, may need to be used more than once, at 7- to 10-day intervals. This is because louse eggs may hatch 7 to 10 days after being laid, allowing the infestation to spread again if they are not killed.
Timeline
It typically takes 1 to 2 weeks of treatment to eliminate a lice infestation. The entire household should be treated at the same time, as lice can easily spread through direct contact. After treatment, lice and their eggs should be removed with a fine-toothed nit comb and some people may choose to repeat treatment.
Prevention
Head lice can be prevented by avoiding direct contact with an infested person and not sharing combs, hats, and other personal items. It is also important to regularly check family members for lice and their eggs.