Out-patient use of beta-blocking agents--prescribing preferences of physicians in training.

Beta-blocking agents are among the most frequently prescribed medications. To investigate the factors that influence their use we analysed the practices of 25 medical residents who provided longitudinal care in the out-patient clinics of a teaching hospital. A computer-based audit identified the 349 patients treated with one of four beta-blocking agents during a 4-month period. The most frequently prescribed was atenolol (48%), followed by metoprolol (28%), propranolol (20%), and nadolol (4%). Ease of use and compliance and continuation of a beta-blocker prescribed by a previous physician emerged as the most influential factors. In contrast, cost of drugs, manufacturers' promotions and advertisements had no significant influence on beta-blocker selection.