Challenges to evidence-based prescribing in clinical practice.

Although there appears to be widespread support of evidence-based medicine as a basis for rational prescribing, the challenges to it are significant and often justified. A multitude of factors other than evidence drive clinical decision-making, including patient preferences and social circumstances, presence of disease-drug and drug-drug interactions, clinical experience, competing demands from more pressing clinical conditions, marketing and promotional activity, and system-level drug policies.