 Septic shock is defined as severe sepsis with hypotension not reversed by adequate fluid resuscitation. This state of distributive shock often results in hypo-perfusion of all major organ systems, including the kidneys, and is a common cause of multi-organ failure. Acute renal failure in the setting of septic shock often leads clinicians to adjust dosing of empiric antibiotics according to the apparent renal function. Renally adjusted antibiotic dosing in septic shock may be insufficient for several reasons. First, renal failure secondary to hypoperfusion often reverses following fluid resuscitation and vasopressor use, leading to subsequent under dosing. Second, a hypoperfusion state theoretically results in a reduction in the amount of antibiotic delivered to the site of infection. Lastly, for drugs with large volumes of distribution or prolonged half lives, large initial doses are required to quickly to achieve therapeutic concentrations. 