Contact & Seborrhoeic Dermatitis

Key points

• Allergic contact dermatitis: type IV hypersensitivity (nickel, rubber, fragrances, hair dye) — patch testing identifies the allergen.
• Irritant contact dermatitis: direct chemical damage (detergents, occupational).
• Seborrhoeic dermatitis: greasy scale of scalp, eyebrows, nasolabial folds (Malassezia); linked to Parkinson's and HIV when severe.
• Management: avoid trigger + emollients + topical steroids; ketoconazole shampoo for seborrhoeic dermatitis.
• Pompholyx: itchy vesicles on palms/soles (dyshidrotic eczema).

Decision points in this pathway

• Allergic suspected (nickel, rubber, fragrance, hair dye)?

The full step-by-step algorithm, including what to do at each branch, opens in the app for approved members.