Clinical features

Patient will usually reveal a history of contact with an allergen (1).

Symptoms generally occur 1-2 days after exposure, but may also appear from several hours to several days post-exposure (1)

• acute / early stages - pruritus, erythema, dryness, and scaling, but vesicles and bullae can develop
• chronic stages - dryness, scaling, fissuring

Areas where skin is thinnest often affected first eg. around eyes before the rest of the face; back of hands and web spaces before palms.

If a topical product is the cause (e.g., medicines, cosmetics, adhesive tape), reactions usually have a well demarcated border (2).

Skin changes often subside gradually within 2-3 weeks after elicitation (3).

Reference:

1. Rashid RS, Shim TN. Contact dermatitis. BMJ. 2016;353:i3299.
2. Usatine RP, Riojas M. Diagnosis and management of contact dermatitis. Am Fam Physician. 2010;82(3):249-55.
3. Astner S et al. Non-invasive evaluation of the kinetics of allergic and irritant contact dermatitis. J Invest Dermatol 2005; 124:351-359