Medroxyprogesterone acetate bioavailability after high-dose intraperitoneal administration in advanced cancer.

Administration of medroxyprogesterone acetate IP in advanced cancer with peritoneal metastases and ascitic effusion generates considerably higher drug plasma levels than those observed after PO or IM treatment. Comparison of areas under the time-concentration curves (AUC) with reference to the three administration routes indicates that after oral administration only 0.2%-17.4% (mean 5.7%; SD 3.77; 40 patients) of the administered dose is absorbed; after IM treatment a daily absorption of 0.7%-7.7% (mean 2.5%; SD 1.66; 30 patients) of the administered dose per injection site was computed.