Pharmaceutical promotion, prior authorisation and the use of erectile dysfunction medications in the US Medicaid population

Abstract To decrease the use of oral erectile dysfunction (ED) medications, US Medicaid programmes have implemented prior authorisation (PA) and other cost-containment policies, such as increasing co-payments and restricting monthly dispensing. However, it is unclear how pharmaceutical promotional activities, such as direct-to-consumer advertising (DTCA) and physician detailing, influence the efficacy of these policies. This study sought to estimate the extent to which such policies could reduce the use of ED medication in the face of pharmaceutical promotions. It determined the dates of cost-containment policies in 35 states and the District of Columbia from 2000 through 2005, and used the generalised estimating equation to estimate the impact of pharmaceutical promotions and cost-containment policies on ED medication use. Higher spending on DTCA was associated with increased ED medication utilisation, but the impact of DTCA was less significant when PA policy was in place. The interaction between spending on detailing and PA was however significant, suggesting that higher spending on detailing significantly increases total ED medication utilisation when PA is implemented. PA and dispensing limit policies are associated with a reduction in ED medication utilisation in the Medicaid population in the presence of pharmaceutical promotions, but PA policies are less effective when the medication is heavily promoted to physicians. Policy makers should consider that cost-containment policies may be differentially sensitive to manufacturers' promotional strategies.