A model of the role of free drug samples in physicians’ prescription decisions

Pharmaceutical companies distribute billions of dollars worth of free prescription drug samples every year giving rise to several concerns about their role in physicians’ prescription decisions including: (1) making physicians view drugs with samples “gifted” to them more favorably than those without samples even though this is not justified on medical grounds; (2) inducing physicians to prescribe the sampled drug simply to garner the goodwill of their patients “happy to go home with free samples”; and (3) overly influencing less-experienced doctors. Interestingly, however, these popular concerns are not supported by findings of extant empirical studies in the medical literature. A review of these findings leads the authors to propose that rather than undermining objective prescription decision-making, free drug samples assist physicians find the best patient-drug match in settings characterized by diagnostic uncertainty. Based on a model of a competitive therapeutic category consisting of two differentiated brands and a physician who is focused on successfully treating his/her patients while minimizing associated costs, the authors show that samples can facilitate a prescription trial to resolve the attendant diagnostic uncertainty. The proposed model of the role of samples yields insights consistent with the findings in the empirical medical literature and also offers several implications for a firm’s optimal allocation of free samples across physicians with varying levels of experience.