Pruritus

Alternative names
Itching

Definition
Itching is a peculiar tingling or uneasy irritation of the skin that causes a desire to scratch the affected area.

Considerations

Itching may be over the whole body (generalized), or only in a particular location (localized). There are many causes of itching, ranging from the simple to the complex.

Insect bites and stings may cause localized itching and skin irritation.

Either localized or generalized itching may be caused by:

     
  • Chemical irritation, such as from poison ivy or stinging nettle  
  • Environmental causes such as sunburn  
  • Hives  
  • Parasites (body lice, head lice, pubic lice)

Generalized itching may be caused by:

     
  • Infectious diseases (chicken pox)  
  • Allergic reactions  
  • Kidney disease  
  • Liver disease with jaundice  
  • Reactions to medications

Common Causes

     
  • Insect bites  
  • Dry skin  
  • Contact dermatitis (poison ivy or poison oak)  
  • Contact irritants (such as soaps, chemicals, or wool)  
  • Atopic dermatitis  
  • Rashes (may or may not itch)  
  • Childhood infections (such as chicken pox or measles)  
  • Aging skin  
  • Allergy caused by food or drugs (antibiotics)  
  • Superficial skin infections such as folliculitis and impetigo  
  • Pregnancy  
  • Hepatitis  
  • Iron deficiency anemia  
  • Parasites such as pinworm  
  • Pityriasis rosea  
  • Psoriasis  
  • Seborrheic dermatitis  
  • Urticaria  
  • Drugs such as antibiotics (penicillin, sulfonamides), gold, griseofulvin, isoniazid, opiates, phenothiazines, or vitamin A

Home Care

For persistent or severe itching, see your health care provider for a precise diagnosis and specific treatment instructions.

In the meantime, there are some steps you can take to help deal with the itch:

     
  • Avoid scratching or rubbing the itchy areas. Keep fingernails short to avoid skin damage from any inadvertent scratching. Family members or friends may be able to help by calling attention to your scratching.  
  • Wear cool, light, loose bedclothes. Avoid wearing rough clothing, particularly wool, over an itchy area.  
  • Take lukewarm baths using little soap and rinsing thoroughly. Try a skin-soothing oatmeal or cornstarch bath.  
  • Apply a soothing lotion after bathing to soften and cool the skin.  
  • Apply cold compresses to an itchy area.  
  • Avoid prolonged exposure to excessive heat and humidity.  
  • Engage in activities that distract from the itching during the day and make you tired enough to sleep at night.  
  • Try over-the-counter oral antihistamines such as diphenhydramine (Benadryl), but be aware of possible side effects such as drowsiness.  
  • Try over-the-counter hydrocortisone cream on localized itchy areas.

Call your health care provider if

Call your provider if itching is associated with other unexplained symptoms, is severe, prolonged, or cannot be easily explained.

Most itching does not require medical evaluation. Try to rule out the obvious causes of itching.

It is sometimes easy for a parent to discern the cause of a child’s itching. Usually a simple visual examination will help you identify any bites, stings, rashes, dry skin, or irritation. Often the cause of itching is fairly obvious, such as a mosquito bite.

Recurrent itching without obvious cause, total body itching, and recurrent hives are all indications that the itching should be evaluated as soon as possible. Such itching may be a symptom of an underlying disease or possibly serious condition.

What to expect at your health care provider’s office
Your health care provider will obtain your medical history and will perform a physical examination.

Medical history questions documenting itching may include the following:

     
  • How long have you had this itch?  
  • Does it itch all the time?  
  • Does it seem to get worse, and has it spread?  
  • What do you think caused this itch?  
  • Have you ever had this kind of itch before? What caused it then?  
  • Do you recall any irritant that you recently came in contact with?  
  • Do you have any allergies or sensitivities?  
  • What medications are you taking?  
  • Have you started using any new products recently? What was it?  
  • Have you used any new soaps, fabric softeners, perfumes, deodorants, fabrics such as wool, or chemicals?  
  • Have you been around animals?  
  • Have you eaten shellfish or nuts recently?  
  • Have you had insect bites recently?  
  • Do you use lotions on your skin?  
  • Have you been in the sun recently?  
  • What part of your body itches?  
  • Is it all over your body (generalized itch)?  
  • Is the itch limited to a specific area? What area?  
  • What does the skin that itches look like?  
  • Is there a rash? If so, are there blisters or scales?  
  • Are you being treated for other medical conditions?  
  • What other symptoms do you have?

If there is no localized infection or skin lesion, diagnostic studies such as blood tests, skin biopsies, or x-rays will focus on finding a systemic (whole body) cause.

Prescribed medications may include topical corticosteroids, antihistamines, or tranquilizers.

Johns Hopkins patient information

Last revised: December 6, 2012
by Simon D. Mitin, M.D.

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All ArmMed Media material is provided for information only and is neither advice nor a substitute for proper medical care. Consult a qualified healthcare professional who understands your particular history for individual concerns.