Smith FC, Stocker SL, Danta M, et al. - In the present study, the researchers tested the safety and pharmacokinetics of metformin in individuals with chronic liver disease (CLD). A cross-sectional survey of patients already prescribing metformin (n = 34) and a prospective study in which metformin (500 mg, immediate release, twice daily) was administered for up to 6 weeks (n = 24) were examined in chronic liver disease patients with and without T2DM. For CLD patients, metformin pharmacokinetics are not adequately altered to raise concerns about unsafe metformin concentrations. There were no unsafe concentrations of plasma lactate observed in metformin-treated CLD patients. Compared with those without cirrhosis, CLD patients with cirrhosis had 23% higher lactate concentrations. Compared with healthy individuals, the ratio of apparent metformin clearance (CL_Met/F) to creatinine clearance was marginally lower in CLD patients.