This study was designed to evaluate the pharmacokinetics and toxicity of paclitaxel administered via an intraperitoneal (i.p.) route for patients with gastric cancer. Fourteen patients with peritoneal dissemination were entered in the trial. Three distinct dose levels from 120 to 180 mg/body were studied. A major pharmacokinetic advantage (550-2,000 fold) for peritoneal cavity exposure compared with the systemic compartment was seen following intraperitoneal delivery of paclitaxel. The dose-limiting toxicity was found to be abdominal pain at 180 mg/body. Grade 2 toxicity included 1 episode of neutropenia and grade 1 toxicities included 1 case of finger-numbness and 2 of alopecia. We conclude that intraperitoneal paclitaxel administration is well tolerated and provides a peritoneal pharmacokinetic advantage for the treatment of peritoneal dissemination.