To the Editor: As Prof. Sharma and Ms. Sommerdyk highlight, optimizing medication management in pregnant women with bipolar disorder is an area with an urgent need for data to drive decision making. The objectives of the Treatment in Psychiatry article (1) were to combine a review of the data on the pharmacokinetic changes of lamotrigine in pregnant women with epilepsy with observations from our case series and to generate recommendations for lamotrigine dosing in pregnant women with bipolar disorder. Sharma and Sommerdyk raise an important point about whether women treated with lamotrigine in pregnancy experience an increase in mood symptoms as a result of declining lamotrigine concentrations. Serum level reductions of psychotropic medications as a result of dosage decreases or drug nonadherence are associated with episode recurrence and symptom worsening. Data on lamotrigine use in pregnant women with bipolar disorder are sparse; however, the literature on managing lamotrigine in women with epilepsy is relevant for guidance about pharmacokinetic changes during gestation. Women with epilepsy experience increased seizure frequency associated with declining lamotrigine levels during pregnancy. Similarly, if the bioavailability of lamotrigine for maintenance treatment of bipolar disorder is not sustained in the pregnant woman, she is at risk for symptom worsening. As Sharma and Sommerdyk recommend, careful symptom monitoring is essential in the gravid woman taking lamotrigine, since pregnancy may increase clearance and lower levels (2). Establishing a baseline serum level at the patient’s therapeutic dose of lamotrigine and adjusting the dosage to maintain the baseline level increases the likelihood of preventive efficacy.