How Do You Get Lice?

What Are Lice?

Lice are transmitted through direct contact with an infected person, or by sharing items from an infected person such as clothing, bed linens, furniture, brushes and combs, towels, pillows, and toys.

Lice are parasites that feed on human blood and can be found on people’s bodies. 

Lice found on different parts of the body are different. There are three types of lice that live on humans:

  • Pediculus humanus capitis: head louse, lives on the scalp and in the hair
  • Pthirus pubis: pubic louse, also called “crabs,” lives in pubic hair, eyebrows, eyelashes, armpits, facial hair, and other areas
  • Pediculus humanus corporis: body louse, feeds on the body and can live in clothing (uncommon)
    • Body lice are the only type known to spread disease

What Are Symptoms of Lice?

Symptoms of lice vary depending on the body part affected but include itching in the area where the lice are. 

Symptoms of head lice include: 

  • Itching on the scalp
  • Feeling something moving or tickling in the scalp and hair
  • Sores on the head from scratching that may become infected
  • Difficulty sleeping: head lice are most active in the dark

Symptoms of body lice include: 

  • Intense itching and rash on the body
  • Thick and discolored skin in areas infested for a long time
  • Sores on the body from scratching 
  • May become infected 

Symptoms of pubic lice include:

  • Itching in the genital area
  • Nits (lice eggs) or crawling lice visible to the naked eye

What Causes Lice?

Lice are transmitted through direct contact with an infested person, or by sharing items from an infested person such as clothing, bed linens, furniture, brushes and combs, towels, pillows, and toys.

How Are Lice Diagnosed?

Lice are diagnosed by visualization of lice or nits (louse eggs), which sometimes can be seen with the naked eye, however, lice may be difficult to see unless filled with blood from a recent meal. 

If lice are suspected but are not able to be visualized, a fine-toothed louse comb may help identify live lice. In some cases, use of a magnifying lens may be necessary to see them. The presence of nits can be confirmed by a special lamp which causes nits to glow a pale blue color, or by dermoscopic examination. 

What Is the Treatment for Lice?

Home remedies can treat itching caused by lice bites but they do not get rid of the infestation. The infestation needs to be treated. 

Lice infestations are initially treated by improving the personal hygiene of the infested person. Launder clothing, bedding, and towels used by the infested person with hot water (at least 130°F) and machine dry using the hot cycle. After that, both over-the-counter (OTC) and prescription shampoos and medications may be used.

Lice treatment includes both over-the-counter (OTC) and prescription shampoos and medications. 

Over-the-counter lice medications include:

  • Pyrethrins combined with piperonyl butoxide (A–200, Pronto, R&C, Rid, and Triple X)
  • Permethrin lotion, 1% (Nix)

Prescription head lice medications include:

  • Benzyl alcohol lotion, 5% (Ulesfia lotion)
  • Ivermectin lotion, 0.5% (Sklice)
  • Malathion lotion, 0.5% (Ovide)
  • Spinosad 0.9% topical suspension (Natroba) 
  • Lindane shampoo 1%

Excessive scratching can lead to sores and infections which may need antibiotics. Consult a dermatologist if you suspect you have lice bites. 

There are some home remedies that recommend applying oils, mayonnaise, or vinegar to the head or body overnight to suffocate the lice. These remedies don’t always work and can be messy and time consuming. Talk to your doctor before trying any home remedy to get rid of lice. 

Natural home remedies will not get rid of lice but may help relieve itching caused by lice bites: 

  • Wash the area thoroughly with soap and water
  • Wrap an ice pack in a towel and apply to the affected area 
  • Mix 1 teaspoon baking soda with 3 teaspoons of water, apply paste to the affected area, and let sit for 10 minutes. Rinse. Repeat as needed. 
  • Pat lemon juice on the affected area (lemon juice can make the skin sensitive to sunlight so avoid the sun)
  • Soak a cotton ball in witch hazel, apply to the affected area and let sit for 10 minutes
  • Apply Aloe vera gel to the bites
  • Apply apple cider vinegar to the bites
  • Make a fine paste with oatmeal and water, apply to the affected area, let sit for 20 to 30 minutes, rinse with water. Repeat for a couple of days. Or mix 1/2 cup of colloidal oatmeal into a bathtub filled with warm water and soak for 10 to 15 minutes. 
  • Apply a cucumber slice to the affected area and let sit for 20 to 30 minutes.
  • Moist, cool tea bags may ease swelling and itching. Cool a moist tea bag in the refrigerator, and place on the affected area for 15 minutes. 

How Do You Prevent Lice?

Prevention of lice infestation includes:

  • Do not share beds, couches, pillows, carpets, or stuffed animals of an infested person.
  • Machine wash and dry clothing, bedding, and other items an infested person used during the 2 days before treatment in hot water (130°F) and the dry on high heat. 
  • Vacuum the floors and furniture.

Prevention of head lice infestation includes:

  • Avoid head-to-head (hair-to-hair) contact during play, sports, on the playground, at slumber parties, or camp
  • Do not share clothing, especially head wear 
  • Do not share hair care items such as brushes, combs, hair accessories, or towels

Prevention of body lice infestation includes:

  • Bathe regularly and wear clean clothes that are laundered in hot water and dried on high heat at least once a week
  • Fumigate or dust with chemical insecticides as needed to control and prevent the spread of body lice for certain diseases 

Prevention of public lice infestation (“crabs”) includes:

  • Avoid sexual contact with infested person(s) and their sexual partner(s) until everyone has been treated 
  • Persons with pubic lice should be examined and treated for other possible sexually transmitted diseases (STDs