What is the treatment for pediculosis capitis (head lice) in adults?

From the Guidelines

For adult head lice treatment, I recommend starting with over-the-counter pediculicides containing permethrin 1% (like Nix) or pyrethrins with piperonyl butoxide (like RID), as these are the most studied and recommended treatments with low mammalian toxicity 1. The treatment should be applied according to package directions, typically leaving it on for 10 minutes before rinsing.

• A second treatment is usually needed 7-10 days later to kill newly hatched lice.
• For persistent infestations, prescription options include malathion 0.5% (Ovide), benzyl alcohol 5% (Ulesfia), ivermectin 0.5% lotion (Sklice), or spinosad 0.9% (Natroba) 1. Regardless of the treatment chosen, it is essential to combine medication with thorough wet-combing using a fine-toothed lice comb to remove lice and nits.
• Wash bedding, clothing, and personal items used in the past 48 hours in hot water (at least 130°F) and dry on high heat.
• Items that cannot be washed should be sealed in plastic bags for two weeks. Head lice cannot survive more than 1-2 days without feeding on human blood, and they do not infest pets. The treatment works by either paralyzing the lice's nervous system or suffocating them, preventing their ability to feed and reproduce. It is crucial to note that resistance to permethrin and pyrethrins has been reported, and malathion 0.5% can be used in people who are 24 months of age or older when resistance to these products is documented or when treatment with these products fails despite their correct use 1.

From the FDA Drug Label

Adults and children 2 years and over ... if either lice or nits are found, treat with this product Treat apply thoroughly to DRY HAIR or other affected area. For head lice, first apply behind ears and to back of neck. allow product to remain for 10 minutes, but no longer use warm water to form a lather, shampoo, then thoroughly rinse for head lice, towel dry hair and comb out tangles Remove lice and their eggs (nits) se a fine-tooth or special lice/nit comb a second treatment must be done in 7 to 10 days to kill any newly hatched lice Malathion lotion is indicated for patients infected with Pediculus humanus capitis (head lice and their ova) of the scalp hair.

The treatment for pediculosis capitis (head lice) in adults is to:

• Apply pyrethrin or malathion topical products to dry hair
• Leave the product on for 10 minutes before rinsing
• Use a fine-tooth or special lice/nit comb to remove lice and nits
• Repeat the treatment in 7 to 10 days to kill any newly hatched lice 2, 3

From the Research

Treatment Options for Pediculosis Capitis (Head Lice) in Adults

• The optimal therapy for head lice includes malathion lotion 0.5% repeated in one week, left on for 30 minutes to 8 hours 4
• Spinosad topical suspension 0.9% repeated in one week, left on for 10 minutes, is another option 4, 5
• Permethrin 1% lotion or shampoo is considered a first-line pharmacologic treatment for pediculosis 6
• Wet combing is an effective nonpharmacologic treatment option 6
• Isopropyl myristate/ST-cyclomethicone solution and dimeticone can be considered as second-line therapies when there is evidence of treatment failure 7
• Topical ivermectin 0.5% lotion is a safe and efficacious treatment for head lice, but it should be reserved as a third-line treatment due to limited clinical experience, prescription requirement, and high cost 8

Key Considerations

• Treatment of close contacts is essential to control outbreaks and repeated infestations 4, 6
• Washing affected clothing and bedding is necessary to prevent re-infestation 6
• Environmental decontamination, such as placing fomites in a dryer at 60 °C for 10 minutes, may be helpful in preventing re-infestation 4