Salivary paracetamol elimination kinetics during the menstrual cycle.

Studies were done to examine the influence of the menstrual cycle on the elimination kinetics of paracetamol. Salivary concentrations of paracetamol were determined after oral administration of 1 g of paracetamol on day 3, 10, 14, 20 and 25 of the menstrual cycle in normal healthy women volunteers with regular menstrual cycles. There was no significant difference in elimination half-life (t 1/2) or metabolic clearance rate (CL) between the various days of the menstrual cycle. The result suggests that paracetamol kinetics are not altered by the hormonal changes occurring during the menstrual cycle.