OBJECTIVE: To evaluate the impact of the expansion of access to medicines by the Programa Farmácia Popular do Brasil (PFPB – Brazilian Popular Pharmacy Program) on the indicators of hospitalizations and deaths by hypertension and diabetes. METHODS: To estimate the impact of the Brazilian Popular Pharmacy Program, the statistical model of fixed-effect difference in differences was used, considering: the divisions Rede Própria (RP – Proprietary Network) and Rede Conveniada (RC – Partnership Network); the exposure time of the municipality to the program; intramunicipal density, measured by the number of accredited establishments; and the coverage spillover effect into patients from nonparticipating municipalities. Data from 5,566 municipalities were used, for the period from 2003 to 2016, including: (i) administrative records of the PFPB, Sistema de Informações sobre Mortalidade (SIM – Information System on Mortality), and Sistema de Informações Hospitalares (SIH – Hospital Information System); ii) other health data managed by the Departamento de Informática do SUS (DATASUS – Department of Informatics of SUS); iii) sociodemographic data produced by the Brazilian Institute of Geography and Statistics (IBGE); and iv) data from the Relação Anual de Informações Sociais (RAIS – Annual List of Social Information). RESULTS: The expansion of access to medicines for treatment of hypertension and diabetes resulted in a meaningful and statistically significant reduction (p < 0.05) of the number of hospitalizations and deaths by these diseases, in an average annual rate of 27.6% and 8.0%, respectively. The observed impacts were induced by the partnership network, highlighting the density of establishments per 100,000 inhabitants and, above all, the exposure time of the municipality to the program as relevant to the effect. Evidence of a spillover effect and of the maintenance of impacts on different age groups, especially older people, were also observed. CONCLUSIONS: The strategy to expand access to medicines through the PFPB was effective in reducing hospitalizations and deaths by hypertension and diabetes in Brazil during the investigated period. Better understanding the impacts of the program is important to improve the pharmaceutical care policy, to ensure access to cost-effective treatments.