- Concentrations are expressed in mg/L. Clavulanate was used at a fixed concentration of 2.5 mg/L. FAR Faropenem, ETP Ertapenem, clav Clavulanate, microdil Microdilution, MGIT Mycobacterium Growth Incubator Tube. LJ Lowenstein Jensen. Green shading: concentrations achievable in vivo; orange shading: concentrations above those achievable in vivo with current dosing recommendations