Summary A superficial peripheral lymph vessel draining the skin of the upper and medial part of the foot was cannulated on the lower leg of six healthy human volunteers. After 2 days an irritant contact dermatitis was induced by application of 10% sodium lauryl sulphate to the area of skin drained by the lymph vessel. Three days later the spontaneously regressing skin reaction was treated with clobetasol propionate. Lymph was collected twice daily for 7 days, and the levels of various cytokines (IL-1α, IL-1β, IL-2 and soluble IL-2 receptors. IL-6, IL-8, TNF-α, GM-CSF) were determined by ELISA technique. In the majority of the volunteers all cytokines examined were detected in several lymph samples, with the exception of IL-lα and IL-8. In parallel with the clinical symptoms of the contact dermatitis the levels of IL-6 and TNF-α increased 8–l0-fold, whereas for IL-1β, IL-2, IL-2 receptors, and GM-CSF there was a delayed, 2–3-fold increase. These results suggest that cytokines, in particular IL-6 and TNF-α, may actively participate in the immunological reactions in the skin and in the regional lymph nodes during contact dermatitis.