Furosemid 50 mg was administered orally and intravenously to twelve gestotic women for brief periods as a part of a randomized, multicentre clinical trial comparing the efficacy of bed rest and pharmacological treatment. The pharmacokinetic profile was investigated using a gas-liquid chromatographic technique. The plasma half-life after oral and intravenous administration was 115 +/- 37.1 and 71.8 +/- 26.3 min and plasma clearance was 153 +/- 48 and 152 +/- 23 ml/min, respectively (mean +/- SD). Comparative data from healthy pregnant women cannot be obtained for ethical reasons. The results show that gestosis has only a marginal if any effect on the kinetics of furosemide in comparison with published kinetic parameters in healthy volunteers, and patients with renal failure. The new-born babies where checked for side effects according to a protocol in use in a larger regional surveillance programme. No clinical side-effects were attributable to furosemide, but the small size of the group does not permit any definitive conclusions about this aspect.