Cutaneous side effects due to beta-adrenoreceptor-blocking agents are clinically polymorphous. Apparently they appear after several months of continuous therapy. Atypical psoriasiform, lichen planus-like, and eczematous "chronic" rashes are mainly observed. The histological picture usually corresponds to a lichenoid drug reaction. More rarely the so-called pseudo-lupus erythematodes-syndrome is found, which cannot be differentiated from the "idiopathic" disease. Noteworthy extracutaneous manifestations are fibrosing processes, which may be irreversible. Pathogenetically, a delayed hypersensitivity reaction, and an action on the epidermal chalone system (epinephrine-adenylcyclase-c-AMP-complex) may be assumed. Consequently, continuous observation of the skin and mucous membranes is necessary, and medication should be withdrawn if cutaneous side-effects appear.