Contact dermatitis is caused by exposure to an allergen or irritant. If you have red itchy bumps on your skin, especially at the site of contact with some potential irritant or allergen, you may be experiencing contact dermatitis.

Metals (such as nickel, a component of stainless steel and other alloys used to make costume jewelry), latex, cosmetic products and topical medications are among the most frequent triggers of contact dermatitis.

To diagnose contact dermatitis and to find its cause your dermatologist will examine your skin and talk to about your signs and symptoms, questioning you to uncover clues about the trigger substance. To confirm an allergy your doctor will recommend a patch test (small amounts of potential allergens are applied to adhesive patches on your back and your skin reactions are monitored over two or three days).

The acute rash is usually treated with topical or oral corticosteroids and afterwards it is crucial to try to avoid the allergen or the irritant.

Hives (also known as urticaria) are raised itchy bumps. Typically hives appear reddish, and will “blanch” (or turn white) in the center when pressed.

There are two kinds of urticaria, acute and chronic. Acute urticaria occurs at times after eating a particular food or coming in contact with a particular trigger and per definition it does not last longer than 6 weeks. Chronic urticaria is rarely caused by specific triggers and can last for many months or years.