Objectives: To measure the serum concentrations of lamotrigine throughout a complete menstrual cycle.
Methods: Serum concentrations of lamotrigine, estradiol, and progestogen throughout a menstrual cycle were measured in 2 young women not using hormonal contraception.
Results and conclusions: The physiological hormonal fluctuations during an ovulatory cycle were not associated with clinically relevant changes in lamotrigine serum concentrations.