Prescription drugs should be therapeutically validated products which are selected for the treatment of accurately diagnosed diseases according to the principles of evidence-based medicine. However, industrial promotion of pharmaceuticals has meant that drug prescription patterns are not always concordant with these ideals. For example, consideration of the most sold drugs in 4 European countries--Italy, France, Germany and the United Kingdom--in 1992 and 1996 shows that marked variations in the utilisation of therapeutic classes, single active principles, and even routes of administration of the same active principles exist in these countries. To some extent, these differences reflect the influence of promotion by national pharmaceutical companies, but they also arise from other factors, such as the lack of adequate pharmacological training of physicians, the paucity of reliable comparative clinical data to allow clinicians to distinguish between large numbers of more expensive 'me-too' drugs and their prototypes, and the idiosyncrasies of national drug approval and registration systems. In addition, differences in prices across countries as well as the length of time a drug has been on the market may be contributing factors. It is hoped that the creation in 1995 of the European Medicines Evaluation Agency (EMEA), which is working towards centralisation of drug marketing approval in the European Union (EU), will usher in the establishment of a common pharmaceutical culture that will combat some of the variations and inconsistencies in drug prescribing patterns evident in European countries. Adoption of such evidence-based and more rational prescribing patterns should not only reduce the number of unnecessary and perhaps undesirable prescriptions written for patients but also relieve the financial burden on national health services in EU countries.