Plasma concentrations of Interleukin-6 (IL-6), C-reactive protein (CRP) and alpha-2 macroglobulin (alpha-2 MG) were examined in 9 patients with severe drug-induced cutaneous reactions (3 patients with toxic epidermal necrolysis and 6 patients with Stevens-Johnson syndrome). The activity of selected protein was measured using the immunoenzymatic ELISA method: a) in the acute stage of disease, before the treatment was applied and b) after clearing of skin lesions due to effective treatment. In the acute stage of the disease considerably increased plasma levels of IL-6 (p < 0.05) and both acute phase proteins (p < 0.001) were found. After clearing of clinical symptoms the concentrations of the examined proteins lowered towards control. But despite deep decrease, CRP and alpha-2 MG levels were still highly significantly increased (p < 0.001) in comparison with the control values. The results of this study indicate that in severe drug-induced skin reactions the acute phase response can be initiated and that the increased activity of examined proteins is longer observed than clinical symptoms of the disease.