In severely ill patients with cholangitis or complicated cholelithiasis, adequate biliary drainage is crucial as antibiotics will not enter bile in the presence of obstruction.
CT scan is important in assessing need for drainage in severe disease.
Some patients will present with diffuse peritonitis.
Zosyn 3.375 g IV every 8 hr (4 hr infusion)
Levofloxacin 500 mg IV every 24 hr
Metronidazole 500 mg IV every 8 hr