Periorbital dermatitis is common and frequently recalcitrant to treatment. Due to the exposed and visible location, patients often suffer severely from periorbital dermatitis. To determine the frequency and causes of periorbital dermatitis including contact sensitizers. We investigated two cohorts of patients (Erlangen and IVDK without Erlangen) between 1999 and 2004. The differences between the two cohorts with periorbital dermatitis [Department of Dermatology at University Hospital Erlangen (n = 88) and the German Information Network of Departments of Dermatology (IVDK) collective (n = 2035)] were determined by the MOAHLFA (male, occupational dermatosis, atopic eczema, hand dermatitis, leg dermatitis, facial dermatitis, age > or = 40 years) index. Statistically significant factors for periocular eczema are female sex, atopic skin diathesis and age > or = 40 years. In both cohorts allergic contact dermatitis was the main cause of periorbital eczema (Erlangen 44.3%, IVDK 31.6%), followed by periorbital atopic dermatitis (Erlangen 25%, IVDK 14.1%), airborne dermatitis (Erlangen 10.2%, IVDK 1.9%), irritant contact dermatitis (Erlangen 9.1%, IVDK 7.6%), periorbital rosacea (Erlangen 4.5%, IVDK 2.2%), allergic conjunctivitis (Erlangen 2.3%, IVDK included in 'others') and psoriasis (Erlangen 2.3%, IVDK included in 'others'). The most relevant allergens/allergen sources inducing periorbital eczema were consumers' products (facial cream, eye shadow and ophthalmic therapeutics) (31%), fragrance mix (19%), balsam of Peru (10%), thiomersal (10%) and neomycin sulphate (8%); 12.5% of patients with allergic periocular dermatitis could be exclusively elucidated by testing patients' own products. Our data demonstrate the multiplicity of causes for periorbital eczematous disease manifestation, which requires patch testing of standard trays as well as consumers' products to elucidate the relevant contact sensitization.