For a benefit analysis of drug utilization data little reliable information is available. Benefit criteria have to be established for individual classes of drugs as well as for various types of diseases submitted to drug treatment. Antihypertensive therapy is taken as an example of how drug preferences vary from country to country and how prescribing patterns are affected by the appearance of new drugs. In the Federal Republic of Germany, fixed-ratio combinations of reserpine and diuretics are still the leading group of drugs in this field, whereas they have virtually disappeared in Great Britain and Sweden. In the latter two countries, beta-blockers are the most widely prescribed antihypertensives, and also in Germany they rank quite high in sales, but less so in the number of prescriptions. Extreme differences are found in the utilization of cardiac glycosides between Germany and Great Britain, but little is known about the consequences of risk/benefit analyses of either over- or underprescribing of these drugs. It is highly recommended to make further efforts in analyzing drug utilization data and developing studies in drug epidemiology.