- Red or pink rash on one small part of the body (localized)
- Small spots, large spots or solid redness
- Includes redness from skin irritation
Causes of Localized Rash or Redness
- Irritants. A rash in just one spot is usually caused by skin contact with an irritant.
- Plants. Many plants cause skin reactions. Sap from evergreens can cause a red area.
- Pollen. Playing in the grass can cause a pink rash on exposed skin.
- Pet Saliva. Some people get a rash where a dog or cat has licked them.
- Food. Some children get a rash if a food is rubbed on the skin. An example could be a fresh fruit. Some babies get hives around the mouth from drooling while eating a new food.
- Chemicals. Many of the products used in the home can be irritating to the skin.
- Insect Bite. Local redness and swelling is a reaction to the insect's saliva. Can be very large without being an allergy. Kids often get mosquito bites without anyone noticing it.
- Bee Sting. Local redness and swelling is a reaction to the bee's venom. Can be very large without being an allergy.
- Cellulitis. This is a bacterial infection of the skin. The main symptom is a red area that keeps spreading. Starts from a break in the skin (such as a scratched insect bite). The red area is painful to the touch.
- Other Common Causes. Look at the "See Other Care Guide" section. 8 rashes that you may be able to recognize are listed there. If you suspect one of them, go there. If not, use this guide.
Localized Versus Widespread Rash: How to Decide
- Localized means the rash occurs on one small part of the body. Usually, the rash is just on one side of the body. An example is a rash on 1 foot. Exceptions: athlete's foot can occur on both feet. Insect bites can be scattered.
- Widespread means the rash occurs on larger areas. Examples are both legs or the entire back. Widespread can also be on most of the body surface. Widespread rashes always occur on matching (both) sides of the body. Many viral rashes are on the chest, stomach and back.
- The cause of a widespread rash usually goes through the blood stream. Examples are rashes caused by viruses, bacteria, toxins, and food or drug allergies.
- The cause of a localized rash usually is just from contact with the skin. Examples are rashes caused by chemicals, allergens, insect bites, ringworm fungus, bacteria or irritants.
- This is why it's important to make this distinction.
Contact Dermatitis
Contact dermatitis is a common cause of a rash in one area. This is especially true of a small rash that will not go away. Contact dermatitis usually starts as raised red spots. It can change to blisters, as in poison ivy. The rash is itchy. Contact dermatitis is an allergic skin rash. 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.)
- Tanning agents in leather: tops of the feet from shoes or hands from leather gloves
- Preservatives in creams, lotions, cosmetics, sunscreens, shampoos: where applied
- Neomycin in antibiotic ointment: where applied