In the submitted review the authors summarize the most recent steadily increasing findings on free oxygen radicals and their importance in dermatovenereology. The authors analyze the importance of antioxidants and their possible therapeutic effect. Special attention is devoted to the development of free radicals during irradiation of the skin with ultraviolet rays, during photodynamic therapy and in skin tumours. The pathogenetic influence is described in many other clinical units and conditions such as psoriasis, seborrhoic dermatitis, acne, rosacea, autoimmuneconditions, vasculitis, vitiligo, burns, keloids, scleroderma, ulcerations, healing of skin wounds and skin trans- plantations.

        Key words: free oxygen radicals and dermatovenereology - antioxidants and dermatovenereology - ultraviolet radiation