Do Formularies Enhance Patient Safety? THE “PRO ” SIDE

and others have been debating the value of formularies for many years,1 but recently the context has changed somewhat. Whereas the debate used to focus on whether formularies improved therapeutic outcomes and reduced costs,2,3 the emphasis has now shifted to whether they improve medication safety or, conversely, place patients at greater risk of medication-related adverse events.4,5 The recent debate has been fuelled by reports suggesting that the outpatient prescription drug benefit formularies used by large health maintenance organizations in the United States may place some patients, particularly the elderly, at greater risk for adverse drug events.6,7 The involvement of the pharmaceutical industry in the ownership and management of pharmacy benefit management companies in the United States and the questionable substitution practices used by some of thos