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Medical Author:

Gary W. Cole, MD

Gary W. Cole, MD

Dr. Cole is board certified in dermatology. He obtained his BA degree in bacteriology, his MA degree in microbiology, and his MD at the University of California, Los Angeles. He trained in dermatology at the University of Oregon, where he completed his residency.

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Medical Editor:

William C. Shiel Jr., MD, FACP, FACR

William C. Shiel Jr., MD, FACP, FACR

Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.

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Contact Dermatitis Symptoms and Signs

Distinguishing allergic contact dermatitis from irritant contact dermatitis and other forms of eczematous dermatitis can be challenging. A full history and physical examination are frequently necessary.

• A red rash is the usual reaction. It appears immediately in irritant contact dermatitis, but in allergic contact dermatitis, the rash does not appear for one to two days after the exposure.
• Your skin may develop small fluid filled structures (vesicles) that can cause weeping, a characteristic of these sorts of eruptions. This condition is distinguished from hives (urticaria) that produce short-lived itchy welts (wheals). Hives are most often induced by allergic reactions to orally ingested foods and drugs.
• Your skin will itch and perhaps burn. Irritant contact dermatitis can be more painful than itchy.
• Irritant contact dermatitis often affects the hands, which have been exposed by resting in or dipping into a container (sink, pail, tub) containing the irritant.
• Once a reaction starts, it may take as long as four weeks to resolve completely.