Population pharmacokinetics and pharmacodynamics of cefazolin using total and unbound serum concentrations in patients with high body weight

≥60%, 0.5-h infusion of cefazolin 1 g q8h achieved PTA 90%. Overall, cefazolin pharmacokinetics are altered considerably in obese patients. Higher-dose and/or prolonged-infusion cefazolin regimens should be considered in patients with TBW ≥120 kg, particularly those with less-susceptible Gram-negative infections.