- Simulation was carried out for 5 dosage regimens. Percentiles; 10 and 50% (shaded column). MIC values in CAMHB were 2.4 mg/L for 120h_B3_5 (green), 2 mg/L for ECOFF (yellow) and 0.125 mg/L for N100 (grey). Median colistin concentration in luminal intestinal content (gut) expressed in mg colistin/kg intestinal content (blue).