Contact dermatitis
Irritant versus allergic contact dermatitis, the common Australian allergens, patch testing done properly, occupational hand dermatitis, and the look-alikes (contact urticaria, photocontact and systemic contact dermatitis).
Tier 1Condition
Written with AI assistance and fact-checked against the sources below. For exam study, not clinical decisions. How notes are made
At a glance
- Irritant contact dermatitis (ICD) is a direct chemical or physical injury. Allergic contact dermatitis (ACD) is a delayed (type IV) immune reaction in a sensitised person.
- About 80% are irritant. Most occupational skin disease is contact dermatitis, and most of that is hand dermatitis.
- Patch testing is the only way to prove ACD. Prick testing and serum IgE test a different (type I) reaction.
Loading the rest of the note…
Finished reading?
Sources
- Therapeutic Guidelines: Dermatology (contact dermatitis, hand dermatitis)AU/NZTherapeutic Guidelines Limited, Version 5, 2022 (no newer edition found, November 2026)
- Symmetrical drug-related intertriginous and flexural exanthema (StatPearls)StatPearls Publishing (NCBI Bookshelf), 2025
- A to Z of skin, contact dermatitisAU/NZAustralasian College of Dermatologists, current web page (checked November 2026)
- Occupational Dermatology Clinic and patch testing informationAU/NZSkin Health Institute (Melbourne), current web page (checked November 2026)
- Johansen JD et al. European Society of Contact Dermatitis guideline for diagnostic patch testing: recommendations on best practice. Contact Dermatitis 2015;73:195-221European Society of Contact Dermatitis, 2015 (current ESCD patch testing guideline)
- Thyssen JP et al. Guidelines for diagnosis, prevention, and treatment of hand eczema. Contact Dermatitis 2022;86:357-78European Society of Contact Dermatitis, 2022
- Last updated
- 14 November 2026
What changed
- 14 November 2026 Personal emails, About story and Australian-style copy