Bacterial peritonitis is a common complication associated with catheters implanted for intraperitoneal anticancer chemotherapy in patients with extensive ovarian carcinoma. During an ongoing trial of intraperitoneal cisplatin-melphalan vs. cisplatin-gamma interferon, given via an intraperitoneal 'Port-a-cath' catheter, 6 episodes of suspected bacterial peritonitis occurred in 5 patients. Clinical symptoms were present in all episodes and 3 episodes were documented microbiologically. Teicoplanin was given intraperitoneally, 400 mg three times a day on the first day and once daily thereafter. Serum and peritoneal concentrations were measured by bioassay. Despite clinical improvement during therapy, the catheter was removed in 4 out of 5 patients after the end of intraperitoneal teicoplanin, due to the presence of infection. Additional patients are required to evaluate the efficacy of intraperitoneal teicoplanin in the treatment of catheter-related peritonitis associated with anticancer intraperitoneal chemotherapy.