Concentrations of tinidazole in body fluids and tissues in gynaecological patients.

The concentrations of tinidazole in various tissues and body fluids were studied in gynaecological patients after a single 2g oral dose. Tinidazole was determined by the agar-diffusion technique using a strain of Clostridium bifermentans. Reliable estimates of concentrations down to 0.5 microng/ml could be obtained. Dichloromethane extraction of tinidazole added to various tissues in known amounts gave a recovery of 100 +/- 10%. Peak serum values of 32-52 microng/ml were reached 3-6h after the administration. The concentrations in peritoneal fluid, obtained at operation 8.5-15h after the intake, varied between 16 and 40 microng/ml. Specimens from the Fallopian tubes yielded 15-26 microng tinidazole/g tissue; similar levels were obtained specimens from myometrium, endometrium, portio, vaginal secretions, omental fat, and cutis. It is concluded that, with the given dose, tinidazole concentrations are achieved in fluids and tissues of the female genital tract that are far in excess of those that should be therapeutical in infections caused by microorganisms know to respond to nitroimidazole treatment.