Non-medical switching of prescription medications, brand-name drugs and out-of-pocket spending on medicines among Peruvian adults

Objectives: This study evaluated the association between non-medical switching of prescription medications (NMSPM) with brand-name drugs and out-of-pocket spending (OPS) on drugs among Peruvian adults. Methods: We conducted a secondary analysis of the National Survey of User Satisfaction Health using an analytical cross-sectional design. We included 3155 adults who went to drugstores and pharmacies with prescriptions. The independent variable was the self-reported NMSPM. The outcomes were brand-name drug purchase and OPS on drugs. We calculated crude and adjusted prevalence ratios (PR) with their respective 95% confidence intervals (CIs), and the OPS on drugs was analysed using linear regression with crude and adjusted β and their 95% CIs. Key findings: The rate of NMSPM was 6.7%, the proportion of brand-name drug purchases was 55.7% and the average spending on drugs was US$1.73. In the adjusted analysis, the proportion of brand-name drug purchases with NMSPM was higher than without (73.3% versus 54.5%; P < 0.001), with a statistically significant association (adjusted PR = 1.38; 95% CI = 1.29 to 1.47; P < 0.001), and the association between NMSPM and OPS on drugs was statistically significant (adjusted β = 0.23; 95% CI = 0.16 to 0.30; P < 0.001). Conclusions: There is a greater probability of brand-name drug purchases and OPS on drugs when NMSPM exists among adults who go to drugstores and pharmacies in Peru.