Depakote Side Effects Linked to Highest Risk of Major Birth Defects

Results from two European studies appear to indicate that side effects of Depakote more than double the risk of major birth defects when taken by pregnant women when compared to non-valproate based epilepsy drugs. 

The findings were presented at the 9th European Congress on Epileptology, which took place in Rhodes last week. The two studies were the UK Epilepsy and Pregnancy Register and the European and International Registry of Antiepileptic Drugs in Pregnancy (EURAP).

Depakote (dilvalproex) and other valproate-based anti-seizure medications, usually used to treat epilepsy, have long been associated with an increased risk of birth defects. Late last year, the FDA added more stringent warnings about birth defects to Depakote and other drugs in the same class, which also includes Depacon, Depakine and Stavzor.

The UK study found that Depakote and other valproate-based antiepileptic drugs were more than twice as likely to cause major congenital malformations when used by pregnant women than Tegretol (carbamazepine) and Lamictal (lamotrigine), with an overall risk of more than 6%.

The EURAP study set the odds of a Depakote birth defect even higher, at 9.3%, and still nearly double the risk of Tegretol. The EURAP findings, which are still preliminary at this point, indicated there was a dose-based relationship between all antiepileptic drugs and birth defects.

The new studies come on the heels of research published last month in the New England Journal of Medicine, which found that using Depakote increased the risk of six major types of birth malformation, including spina bifida, cleft palate, abnormal skull development, malformed limbs, holes in the heart and urinary tract problems.

Pregnancy problems with Depakote have been long recognized. A “black box” warning has been on the medication’s label since 2006, warning about potential Depakote birth defects associated with use of the drug during pregnancy. A study done that year found that about 20% of babies born to mothers taking Depakote suffered serious problems, as opposed to other drugs which only had rates of between 1% and 10.7.

Abbott Laboratories, the creator of Depakote, is currently being probed by the U.S. Department of Justice (DOJ) over its sales and marketing of the drug. Federal investigators are looking into whether the company violated Medicare or Medicaid reimbursement laws. Depakote was first approved by FDA in 1983. Depakene, the first drug of the class, was approved in 1978. A number of individuals are also reviewing potential Depakote lawsuits against the drug maker for failing to warn about the risk of birth defects and malformations.