Head Lice

Walk-in Dermatology > Head Lice
Head Lice

What are head lice?

Head lice are small parasitic insects that feed on blood from your scalp. An infestation of head lice is called pediculosis capitis. These tiny insects most often infect the scalp of children, spreading by direct contact from the hair of one child to another. Head lice do not carry diseases but may cause itching and discomfort.

What causes head lice?

Head lice are naturally attracted to the warm environment near the scalp. Female head lice secrete a sticky substance that binds their eggs to human hair close to the scalp. Eggs typically hatch within 9 days. The emerging nymphs develop into mature lice within another 12 days and may live for up to a month.

How dermatologists diagnose head lice

Your dermatologist will diagnose head lice with a close visual inspection of the hair and scalp, possibly using a magnifying glass. The lice are smaller than a grain of rice. Running a fine-toothed comb through the hair may pull off lice eggs, which are called nits, confirming the diagnosis.

How dermatologists treat acne

There are several over-the-counter lice treatment products that can be effective in treating lice. It is important to follow the directions carefully and retreat if instructed in 7 to 9 days.

Your dermatologist may prescribe a medicated shampoo to kill head lice. This product may come with a special comb to run through the hair for removing nits. Your dermatologist will also likely recommend thoroughly laundering bed linens and bath towels and cleaning personal products that have come in contact with the hair or scalp, such as a hairbrush where head lice could migrate. Personal items that may not be washable, such as hats, can be placed in a sealed plastic bag for two weeks. Any head lice inside will die of starvation. Brushes and combs can be disinfected by soaking in hot, soapy water for at least 10 minutes, which should destroy any lingering head lice.

If you are concerned about head lice, click here to schedule an appointment with our board-certified dermatologists or walk into Walk-in Dermatology at your convenience for immediate evaluation.