SINGLE-DOSE AND MULTIPLE-DOSE PHARMACOKINETICS OF A LOW-DOSE ORAL-CONTRACEPTIVE IN WOMEN WITH CHRONIC-RENAL-FAILURE UNDERGOING PERITONEAL-DIALYSIS

OBJECTIVE: Our purpose was to compare the pharmacokinetic parameters o f oral administration of a 35 mug ethinyl estradiol, 1 mg norethindron e pill in peritoneal dialysis patients and normal women. STUDY DESIGN: A single-dose study was performed with five patients and four control s, followed by a multiple-dose study with five subjects in each group. Pharmacokinetic parameters were calculated by noncompartmental analys is and statistical analysis performed with Mann-Whitney U testing. RES ULTS: There is no difference in the pharmacokinetic parameters for nor ethindrone in peritoneal dialysis patients compared with normal women. During multiple dosing an increased area under the concentration curv e and decreased apparent oral clearance was observed for ethinyl estra diol in peritoneal dialysis patients compared with normal women. CONCL USION: Peritoneal dialysis patients have decreased apparent oral clear ance of ethinyl estradiol, leading to slightly higher serum concentrat ions compared with women with normal renal function. The clearance of norethindrone is the same in peritoneal dialysis patients and normal w omen.