Local and systemic effect of ultraviolet irradiation (UVB and UVA) on human allergic contact dermatitis.

In subjects hypersensitive to nickel we have investigated local and systemic effect of whole body exposure of cumulative suberythema UVB doses as well as solarium-UVA exposure. UVB possesses both locally and systemically a suppressive effect on human allergic contact dermatitis, but UVA has no such effect. The systemic suppressive effect of UVB might be of therapeutic importance in patients with severe chronic dermatitis of the hands when adding this effect to a local suppressive effect. Also, patch testing should not be performed during UVB and/or overt sun exposure.