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5 Fast Facts About Underarm Rashes

Beware of Allergens

Contact dermatitis is a very common cause of skin irritation on the body, including the underarms. Contact dermatitis works just like it sounds -- if something touches your skin that irritates it or causes a reaction, a rash can develop.

If you suspect that skin care products or household chemicals are causing your rash, the best way to avoid contact dermatitis is to identify the offending product and discontinue its use. If your symptoms don't improve, or if you're unable to identify what's causing your rash, see your physician -- he or she can test for a specific allergy [source: Mayo Clinic].