Levels of Cefazolin in Human Bile

The concentrations of cefazolin in human bile were studied in two patients with normal biliary tracts and in 14 patients with biliary tract disease. Cefazolin was excreted into the bile within 90–120 min after injection. In both normal patients and in patients without obstructive biliary disease, the concentration of cefazolin in bile after four doses was usually at least three times the levels in serum. In view of the relatively high levels in bile, cefazolin may be useful in the treatment of biliary infections due to susceptible bacteria.