Lice are little insects that inhabit on humans and feed on blood. An infestation occurs when a big number of lice inhabit and multiply on a person.

Most common symptom: Itching due to an allergic reaction to lice saliva. Itching depends on:

  • the number of exposures
  • inherent sensitivity of person

For first time cases: may take several weeks or months for itching to start or to be noticed.

Subsequent exposures: it may take just 2 days before itching starts due to the faster response time of the immune system to a condition it is already familiar with.

Varying symptoms of lice infestation depend on the type of lice involved:

Head lice

  • Lice and eggs (called “nits”) can be found on:
    • Hair
    • Back of the neck
    • Behind the ears
  • Lice color can differ from white to brown to dark gray.
  • Eggs are small round or oval shaped that are stuck near the scalp and do not move when the surrounding scalp is moved.
  • If a person keeps scratching, he may cause sores to form and break skin on the scalp, making them susceptible to infection. The lymph nodes behind the ears and in the neck may then become tender and swollen.

Pubic lice

  • May cause itching around the following areas:
    • Genitals
    • Anus
    • Armpits
    • Eyelashes and areas with hair
  • Bites may cause small, flat, blue-gray marks hat look like bruises on the torso, thighs, or upper arms.
  • Lice can also be seen on hair shafts
  • Route of transmission tends to be through sexual contact, thus there might be the presence of some other sexually transmitted infections.

Body lice

  • Sores develop in the following areas:
    • Armpits
    • Around the waist
    • Trunk
  • Unlike other types, body lice and eggs are usually not found on the skin but on the seams of the person’s clothing.


  • Visual exam by physician for presence of live lice or eggs (nits) on hair.
    • A fine-toothed comb may be used to help detect lice.
  • Microscopic exam to confirm diagnosis.



Over-the-counter (OTC) medicines for head or pubic lice:

  • Permethrin creme rinse 1
  • Shampoos containing pyrethrins and piperonyl butoxide

Prescription medicines for head lice:

  • Benzyl alcohol 5%: Left on for 10 minute, then rinsed
  • Malathion lotion: left on for 8 to 12 hours, then rinsed. If there are still lice seen 7 to 9 days later, a second treatment has to be performed.

Antihistamines (both prescription and nonprescription) for relief of itching. It may cause drowsiness; check with physician first before use.

Antibiotics for presence of severe skin infection.

For body lice: Wash clothing and bedding in hot water [54.5°C or higher] in a washing machine to kill lice and eggs.

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