Contact dermatitis is skin inflammation from something that touches the skin, either an irritant that damages it directly or an allergen that triggers a delayed immune reaction. Common causes include soaps, wet work, nickel, fragrances, rubber and poison ivy.
Key symptoms
- Itchy red rash where the skin touched the substance
- Burning or stinging, mostly with irritants
- Blisters or oozing in acute allergic reactions
- Dry, cracked, thickened skin when it lasts a long time
What you find on exam
- Rash shaped like the contact: a patch under a watch or belt buckle
- Sharp borders that match the exposed area
- Blisters in streaks or lines after poison ivy
- Hands, face and eyelids are common sites
Tests
- Detailed history of work, hobbies, skin products and jewelry
- Patch testing to find the allergen in chronic or recurrent cases
- KOH prep if a fungal infection is possible
Treatment basics
- Identify and avoid the cause; wear gloves for wet work
- Topical corticosteroids, stronger on the hands and milder on the face
- Cool compresses for oozing and emollients to repair the skin barrier
- Oral prednisone tapered over 2 to 3 weeks for severe or widespread reactions
- Oral antihistamines may help sleep but do not treat the rash
Red flags
- Swelling of the face, lips or tongue, or trouble breathing
- Widespread rash or blistering of large areas
- Pus, honey-colored crusts or fever suggesting infection
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Sources: NCCPA PANCE Content Blueprint; NBOME COMLEX-USA clinical presentations; AAMC Core Entrustable Professional Activities (Core EPAs). Written by Making Synapses. Making Synapses is not affiliated with these organizations.