Head lice are small, wingless insects that feed on human blood. They’re only found as parasites on humans.

Female head lice lay small oval-shaped eggs (nits) on hair. The eggs measure 0.3 to 0.8 millimeters. The eggs hatch in about 7 to 10 days and must have human blood within 24 hours to survive.

Head lice become sexually mature in about 8 to 10 days. They live for about 30 to 40 days.

Anecdotal reports suggest apple cider vinegar is effective for treating and preventing head lice.

However, research is lacking and not supportive.

In fact, a 2004 study doesn’t support the use of vinegar. Researchers compared six popular alternative remedies for treating head lice infestations, including:

  • vinegar
  • isopropyl alcohol
  • olive oil
  • mayonnaise
  • melted butter
  • petroleum jelly

They found vinegar was actually the least effective treatment method for getting rid of lice or suppressing the hatching of nits.

Vinegar wasn’t the only home remedy that didn’t do well. No home treatment prevented lice from laying eggs. Even with prolonged exposure, most home remedies were unable to kill nits. But only applying petroleum jelly killed a significant amount of lice.

According to the Penn State Department of Entomology, vinegar isn’t effective in ungluing nits from the hair shaft.

Over-the-counter products

Your doctor will likely suggest over-the-counter shampoos with permethrin (Nix) or pyrethrin (Rid) as the first step to treat an infestation. You can find Nix and Rid shampoos online.

Prescription oral medication

If your head lice are a strain that have developed resistance to permethrin and pyrethrin, your doctor might prescribe an oral medication, such as ivermectin (Stromectol).

Prescription topical medication

Your doctor might also prescribe topical medication to put on your scalp and hair, such as:

  • spinosad (Natroba)
  • malathion (Ovide)
  • benzyl alcohol lotion (Ulesfia)
  • ivermectin lotion (Sklice)

Even if you’re using prescription medication, there are still a number of steps you should take when handling an infestation of head lice, including:

  • Check the family. Make sure others in the household don’t have head lice. If they are, start treatment.
  • Comb hair. Use a fine-toothed comb to physically remove lice from your wet hair.
  • Wash bedding, clothes, etc. Bedding, stuffed animals, hats, clothing — anything that might have been contaminated — should be washed in soapy, hot water that’s at least 130ºF (54ºC). Dry for at least 20 minutes on high heat.
  • Wash brushes and combs. Wash brushes just like clothing and bedding, or soak them for an hour in rubbing alcohol.
  • Seal up items. For items that can’t be washed, seal them in an airtight container for a week or two.

Although apple cider vinegar hasn’t been scientifically proven to work, many people have reported success using it.

If you decide to use apple cider vinegar, understand that it might not work at all. If it doesn’t, talk with your doctor. They can help you select the most effective and least toxic way to manage your head lice infestation.

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