A 28-year-old woman with a history of bipolar disorder, who has been stable on valproate for the last three years, presents for consultations she wishes to become pregnant. She and her husband inquire about the best pharmacotherapy options for her.
Which of the following medications would be most appropriate considering her desire to become pregnant?
– Olanzapine (Zyprexa)
Although no medication is without risk during pregnancy, lithium carbonate (absolute risk of Epstein’s anomaly is 0.05-0.1%) has far fewer risks than valproic acid (1-2% for neural tube defects, and higher for other neurodevelopmental effects) or carbamazepine (0.5-1% neural tube defects).
Incomplete data exists regarding lamotrigine; therefore it should be avoided until more data is available.
While olanzapine is not known to directly cause teratogenic effects, the increased risk of impaired glucose tolerance and weight gain predisposes the mother and infant to other obstetrical complications, and therefore should be avoided.