Lamictal XR and Pregnancy
In clinical studies of pregnant animals, large doses of the active ingredient in Lamictal XR (extended-release lamotrigine) caused problems such as low fetal weight and slow bone development. It is hard to say with certainty that Lamictal XR is safe for pregnant women. However, as a pregnancy Category C medication, it may be prescribed as long as the benefits outweigh the risks.
Is It Safe for Pregnant Women to Take Lamictal XR?Lamictal® XR™ (extended-release lamotrigine) is a prescription drug approved to treat partial-onset seizures. Based on the results of animal studies, Lamictal XR may not be safe for use in pregnant women.
What Is Pregnancy Category C?
The U.S. Food and Drug Administration (FDA) uses a category system to classify the possible risks to a fetus when a specific medicine is taken during pregnancy. Pregnancy Category C is given to medicines that have not been studied in pregnant humans but do appear to cause harm to the fetus in animal studies.
In addition, medicines that have not been studied in any pregnant women or animals are automatically given a pregnancy Category C rating.
In animal studies, large doses of lamotrigine (the active ingredient in Lamictal XR) given to pregnant mice and rats caused low fetal weight and slow bone development. Animal studies also suggest that lamotrigine may increase the risk of miscarriage and stillbirth in rats, and may cause behavioral changes in the offspring that survive.
Also, lamotrigine decreases folic acid in the body. Since folic acid helps prevent birth defects, it might be expected that lamotrigine would increase the risk of birth defects. However, animal studies have not shown an increased risk of birth defects due to lamotrigine.
In humans, there is some preliminary evidence that Lamictal XR may increase the risk of cleft lip or cleft palate.
If you and your healthcare provider decide that it is best for you to continue taking Lamictal XR, your healthcare provider may suggest a higher-than-usual dose of folic acid, as this may help protect the fetus.
If you would like, your healthcare provider can submit information about you and your pregnancy to the Lamictal Pregnancy Registry, a service that collects information on the use of Lamictal during pregnancy. Your information would be used to help determine if Lamictal XR causes problems in pregnant women. Talk to your healthcare provider if you would like to be included in the registry.