A perspective on nonadherence to drug therapy: psychological barriers and strategies to overcome nonadherence.

Medication adherence represents an inefficiency and ongoing challenge within medical care. The problem has been long-recognized - indeed, the research literature contains thousands of articles on the topic. Nonetheless, because of the complex nature of the problem, it still cannot be considered to be solved. Reasons for nonadherence are myriad but psychological barriers to adherence are most difficult to mitigate and, thus, are the focus of this paper. The present narrative review sketches a summary of theoretical models commonly utilized to understand and help address medication nonadherence; uses a patient-centered care approach to contextualize the problem of nonadherence to drug therapies; and then outlines a set of best-practice recommendations based on the extant data and framed from the perspective of the Information-Motivation-Strategy model.