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Symptoms

By Mayo Clinic staff

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Illustration showing nits on hair Head lice

Signs and symptoms of lice include:

  • Intense itching.
  • Tickling feeling from movement of hair.
  • Lice on your scalp, body, clothing, or pubic or other body hair. Adult lice may be about the size of a sesame seed or slightly larger.
  • Lice eggs (nits) on hair shafts. Nits resemble tiny pussy willow buds. Nits can be mistaken for dandruff, but unlike dandruff, they can't be easily brushed out of hair.
  • Small, red bumps on the scalp, neck and shoulders.

When to see a doctor
Usually you can get rid of lice by taking self-care steps that include using nonprescription shampoo that's specifically formulated to kill lice.

However, see your doctor if:

  • Nonprescription shampoo doesn't kill the lice — your doctor can prescribe a stronger, prescription shampoo
  • You're pregnant — don't use any anti-lice shampoo until you talk to your doctor
  • You have any infected hives or skin abrasions from scratching
Causes Definition
References
  1. Head lice: Frequently asked questions. Centers for Disease Control and Prevention. http://www.cdc.gov/parasites/lice/head/gen_info/faqs.html. Accessed Feb. 14, 2012.
  2. Body lice: Frequently asked questions. Centers for Disease Control and Prevention. http://www.cdc.gov/parasites/lice/body/gen_info/faqs.html. Accessed Feb. 14, 2012.
  3. Pubic "crab" lice: Frequently asked questions. Centers for Disease Control and Prevention. http://www.cdc.gov/parasites/lice/pubic/gen_info/faqs.html. Accessed Feb. 14, 2012.
  4. Mandell GL, et al. Mandell, Douglas, and Bennett's Priciples and Practice of Infectious Diseases. 7th ed. Philadelphia, Pa.: Churchill Livingstone Elsevier; 2010. http://www.mdconsult.com/book/player/linkTo?type=bookPage&isbn=978-0-443-06839-3&eid=4-u1.0-B978-0-443-06839-3..00293-9. Accessed Jan. 20, 2010.
  5. Goldstein AO, et al. Pediculosis capitis. http://www.uptodate.com/index. Accessed Feb. 16, 2012.
  6. Longo DL, et al. Harrison's Online. 18th ed. New York, N.Y.: The McGraw-Hill Companies; 2012. http://www.accessmedicine.com/content.aspx?aID=2898131. Accessed Feb. 17, 2012.
  7. Burkhart CN, et al. Fomite transmission in head lice. Journal of the American Academy of Dermatology. 2007;56:1044.
  8. Head lice: Treatment. Centers for Disease Control and Prevention. http://www.cdc.gov/parasites/lice/head/treatment.html. Accessed Feb. 14, 2012.
  9. Body lice: Treatment. Centers for Disease Control and Prevention. http://www.cdc.gov/parasites/lice/body/treatment.html. Accessed Feb. 14, 2012.
  10. Pubic "crab" lice: Treatment. Centers for Disease Control and Prevention. http://www.cdc.gov/parasites/lice/pubic/treatment.html. Accessed Feb. 14, 2012.
  11. Mumcuoglu KY, et al. Repellency of citronella for head lice: Double-blind randomized trial of efficacy and safety. Israel Medical Association Journal. 2004;6:756.
  12. Semmler M, et al. Repellency against head lice (Pediculus humanus capitis). Parasitology Research. 2010;106:729.
  13. Frankowski BL, et al. Head lice. Pediatrics. 2010;126:392.
DS00368 May 22, 2012

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