A review of patient perspectives on generics substitution: what are the challenges for optimal drug use

Abstract

Introduction: With a few exceptions, generic drug use has been promoted in western countries by allowing pharmacists to substi- tute drugs defined as therapeutically equivalent generics. The aim of this literature review is to summarise the research on the patients' perspectives of generics substitution in the western world between 2000 and 2011 with special emphasis on the challenges these attitudes present for optimal drug use. Methods: A literature search was undertaken in MEDLINE (PubMed), Embase (Ovid), and SciVerse Scopus with the aim of identifying all the peer reviewed, original research articles concerning patient perspectives on generics substitution in western countries publi- shed between 1 January 2000 and 1 March 2011. Results: The 20 studies included in this review indicate that close to one-third of all patients were uneasy about having their drug(s) substituted generically. Between 8-34% of patients reported poorer effects and/or new side effects after a change—except for anti- epileptic drug users from which the number of reports was even higher. Poor awareness of generics substitution caused confusion and reduced the patients' willingness and ability to take their medication as prescribed. Patients' acceptance of generics substitution was influenced by age, educational levels, perceptions about disease, generic drug information, and who informed them about the change. The studies consistently suggested a continuing need for information directed at patients and an increased involvement of physicians. Conclusion: This literature review suggests that although generics substitution is well accepted by the majority of patients, about one-third of the patients report negative experiences which may lead to poor adherence and medication errors.