Springdale Mason Pediatrics

Rash Localized - Cause Unknown

Definition

  • Rash or redness on one small part of the body (localized)
  • Red or pink rash
  • Small spots or solid redness
  • Rash can be smooth or bumpy
  • Cause of the rash is unknown

Call or Return If

  • Rash spreads or gets worse
  • Rash lasts for more than 1 week
  • You think your child needs to be seen
  • Your child becomes worse

About This Topic

Causes

  • The cause of a localized rash usually is just from skin contact with something. Examples are rashes caused by chemicals, allergens, or insect bites. Ringworm fungus or bacteria can also cause rashes. It's never a food or drug reaction.
  • Irritant dermatitis. Skin contact with an irritant (such as a harsh chemical). This is the most common cause of new localized rashes. Usually, it's not itchy. If it's just on the fingers, it's usually due to a soap or hand cream. Rubber gloves can also be a cause.
  • Contact dermatitis. Skin contact with an allergic substance. If the rash is very itchy, the cause is probably this. The location of the rash may suggest the cause:
  • Poison ivy or oak. Exposed areas, such as the hands.
  • Nickel (metal). Anywhere the metal has touched the skin. (Neck from necklaces, earlobe from earrings, or fingers from rings. Stomach from metal snap inside pants, wrist from watch, or face from eyeglass frames.)
  • Preservatives in creams, lotions, cosmetics, sunscreens, shampoos: where applied
  • Neomycin in antibiotic ointment: where applied
  • Contact dermatitis usually is an allergic reaction. It lasts 2 to 3 weeks. Most contact dermatitis needs a prescription steroid cream to control itching.

Localized Rashes That Are Easy to Diagnose

  • Athlete's Foot (itchy pink rash between the toes)
  • Impetigo (infected small sores covered by soft yellow scabs)
  • Mosquito Bites
  • Poison Ivy
  • Ringworm (round pink patch that slowly gets bigger)

After Care Advice

Overview:
  • Most new localized rashes are due to skin contact with an irritant.
  • Here is some care advice that should help.
Avoid the Cause:
  • Try to find the cause and avoid it.
  • Consider irritants like a plant (such as evergreens or weeds). Also, chemicals (such as solvents). Irritants also can include fiberglass or soaps. A new cosmetic or new jewelry may also be the cause.
  • A pet may carry the irritant. Also, some children react directly to pet saliva.
Do Not Use Soap:
  • Wash the red area once with soap. Reason: To remove any irritants left on the skin.
  • Then, do not use soaps on it. Reason: Soaps can slow healing.
  • Cleanse the area when needed with warm water.
Steroid Cream:
  • If the rash becomes itchy, put on 1% hydrocortisone cream.
  • No prescription is needed.
  • Use it 3 times per day.
  • Exception: Do not use for suspected ringworm.
Try Not to Scratch:
  • Help your child not to scratch the rash.
  • Cut the fingernails short.
What to Expect:
  • Most of these irritant rashes go away in 2 to 3 days.
Return to School:
  • Your child does not need to miss any child care or school.

Author: Barton Schmitt MD, FAAP
Copyright 2000-2020 Schmitt Pediatric Guidelines LLC
Disclaimer: This health information is for educational purposes only. You the reader assume full responsibility for how you choose to use it.
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