UMEM Educational Pearls

Vancomycin Dosing in the Critically Ill Obese Patient

  • Obesity related changes to drug metabolism and distribution can significantly impact the critically ill obese patient.
  • Many meds can either be underdosed or overdosed depending on which body weight (ideal vs. actual) is used.
  • With the increased incidence of MRSA infections, vancomycin is often included in the initial antibiotic selection for most critically ill ED patients.
  • Importantly, vancomycin is one of the most studied antibiotics in obese patients.
  • Recent guidelines recommend that an initial vancomycin dose of 25-30 mg/kg actual body weight be considered for any critically ill patient, with subsequent dosing dependent upon renal function and trough levels.


Medico CJ, Walsh P. Pharmacotherapy in the critically ill obese patient. Crit Care Clin 2010; 26:679-88.