This study investigates the influences of drug companies' advertising programs on physicians. Of the 446 physicians interviewed, 53.9 percent were visited by pharmaceutical company representatives at least once a day, and 43.5 percent spent 15 minutes or more per day on these visits. With respect to the information delivered by the pharmaceutical company representatives, 67.7 percent of physicians thought it was not reliable, and 62.8 percent reported that it had no effect on their prescription writing. The promotional gifts had little effect on prescriptions for 43.9 percent of physicians, and 80.3 percent reported that these gifts were distributed unequally among doctors according to the drugs they prescribed. Only 23.5 percent of physicians supported the prohibition of promotion programs; 90.6 percent of physicians agreed that drugs are too expensive, and 82.9 percent agreed on the presence of overprescription. The authors evaluate these results and provide some suggestions for improving the sources of information for drug prescribing.