This study aimed to establish a reasonable population pharmacokinetic model for rifampicin taken orally by patients with pulmonary tuberculosis, estimate pharmacokinetic parameters as well as influencing covariates. Blood samples of patients were collected at day 10 – 14 after commencing treatment. Time – concentration data were handled using non-linear mixed-effect model with Monolix 2018. An one-compartment, linear elimination, absorption with transit compartments model was found to be the most suitable for rifampicin. Volume of distribution (33,5 L) and clearance (9,62 L) were found to be influenced by fat-free mass (calculated using Janmahasatian’s method). Absorption-related parameters (Ktr, mean transit time and Ka) were found to have high inter-individual variability. Keywords Rifampicin, population pharmacokinetics, pulmonary tuberculosis. References [1] Christian Lienhardt et al, Target regimen profiles for treatment of tuberculosis: a WHO document (2017).[2] J.G. 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