Therapeutic redundancy as a measure of formulary system effectiveness

ABSTRACT

to investigate the assumption that formilary quality is reflected in the number of redundant therapeutic agents in competitive markets. This inquiry assumes that a formulary system that requires strict adherence to the published clinical research evidence in the drug selection process will minimize the number of redundant therapeutic agents in competitive drug markets by balancing manufacturers promotional influences. Possible explanations for redundant therapeutic products are discussed. Design: a telephone survey was used to compare the number of histamine-2 blockers, angiotensin converting enzyme [ACE] inhibitors, and the number of drugs added to formularies in 1993 in ten randomly selected an four nonrandomly selected university associated teaching hospitals to a similar institution in Saudi Arabia. the difference in the number of histamine -2 blockers in surveyed hospitals formularies and our formulary ranged from no difference in two hospitals to a difference of three more drugs in three institutions. For the ACE inhibitors, the range was from no difference in one hospital surveyed to three more drugs in two hospitals. The proportion of new drugs added to formularies in surveyed hospitals ranged from 25% to 92% versus 37% in our hospital. a formulary system that bases the drug selection process on strict adherence to the published clinical research evidence may reduce the number of drugs in highly competitive therapeutic classes in the formulary. Promotional influence is one possible explanation for redundant therapeutic agents seen in some surveyed hospitals formularies