2 Introduction: Chagas disease (CD) and Tuberculosis (TB) are important health problems in 3 Bolivia. Current treatments for both infections require a long period of time, and unwanted 4 drug-related adverse events (ADRs) are frequent. 5 Purpose: This study aims to strengthen the Bolivian Pharmacovigilance system, focusing on CD 6 and TB. 7 Methods: A situational diagnosis of Pharmacovigilance in the Department of Cochabamba was 8 performed. The use of a new Local Case Report Form (CRF) was implemented, together with 9 the CRF established by the Unidad de Medicamentos y Tecnología en Salud (UNIMED), in 10 several health care centers. Training and follow-up on drug safety monitoring and ADR 11 reporting was provided to all health professionals involved in CD and TB treatment. A 12 comparative analysis of the reported ADRs using the CRF provided by UNIMED, the new CRF 13 proposal, and medical records, was performed. 14 Results: Out of the total patients starting treatment for CD, 35,35% suffered ADR according to 15 the information collected in the medical records, and 25% of them were classified as 16 moderate/severe (MS) types. Only 51,43% of MS ADRs were reported to UNIMED. Regarding 17 TB treatment, 9,89% of the total patients suffered ADR, 44% of them were classified as MS, 18 and 75% of MS ADRs were reported to UNIMED. 19 Conclusions: The reinforcement of the Bolivian Pharmacovigilance system is an ambitious 20 project that should take a long-term perspective and the engagement of national health 21 workers and other stake holders at all levels. Continuity and perseverance are essential to 2 22 achieve a solid ADR reporting system, improving patient safety, drug efficacy and adherence to 23 treatment. 24