Dermatitis Venenata is an allergic reaction caused by contact with which substance?

• A. Chemicals
• B. Heat
• C. Cold air
• D. Water

Answer: (A)

Dermatitis venenata tests your understanding of an allergic contact dermatitis triggered by chemical exposure. This reaction is a delayed, cell‑mediated immune response (a type IV hypersensitivity) that occurs when the skin encounters an allergenic chemical—often plant resins like urushiol or various synthetic chemicals found in cosmetics, fragrances, metals, and preservatives. After sensitization, the reaction typically appears 12–48 hours later as redness, swelling, itching, and sometimes vesicles in the area of contact. The essential point is that the trigger is a chemical substance that the skin has become sensitized to; heat, cold air, or water by themselves do not represent the allergenic trigger for this condition.