Blockers of adrenergic beta-receptors (beta-blockers) are commonly administered in cardiology for coronary heart disease, arrhythmias, hypertension and some cardiopathic treatment. They have been also approved as a therapy of chronic heart failure recently. From pharmacological point of view, cardioselective and non selective beta-blockers (with or without intrinsic sympathomimetic activity) are distinguished. New drugs like celiprolol, carvedilol or sotalol have been developed and so the range of the group still continues to widen out. In toxicological routine practice we meet beta-blockers either in acute intoxication cases or in a control of patient's adherence to prescribed therapy. Dizziness, nausea, weakness, vasoconstriction and bradycardia are their usual undesirable effects, whilst in grave cases of a drug overdose bronchoconstriction, coronary spasms, hypotension and even cardiac insufficiency may occur. The article deals with the possibility of detection and identification of beta-blockers and their metabolites in urine by thin layer chromatography.