Does Your Doctor Know That Topamax Is Linked to Birth Defects?

Washington, DCChances are, you trust your doctor to provide the best possible treatment for whatever ails you. And you likely don’t question your doctor when he or she prescribes medications for that ailment. However, doctors have the difficult and time-consuming task of familiarizing themselves with drug contraindications. This writer, for one, asked her doctor if she knew about the link between Topamax and birth defects. She did not.

Nor did she know that Qnexa, the new weight loss pill, is a combination of the amphetamine phentermine, which suppresses your appetite, and topiramate (marketed as the anti-seizure drug Topamax), which makes you feel full. When doctors need to brush up on a drug’s warnings and side effects, they typically refer to The Physicians' Desk Reference (PDR), which is a commercially published compilation of manufacturers’ prescribing information on prescription drugs that is updated every year. It is financed by the pharmaceutical manufacturers that create the drugs referenced in the PDR. (These two issues - only yearly updates and financed by drug companies - right away alert you to a system that has serious flaws.)

Of course, some drugs are put on the market before they are listed in the PDR. The obesity drug Qnexa made by Vivus, which has been available for patient use since July 2012, likely wasn’t listed in the 2012 PDR issue. Perhaps your doctor doesn’t have time to read a drug’s warning label that lists contraindications.

Here is the scenario: an overweight woman asks her doctor to prescribe a diet drug. Neither the woman nor her doctor knows that she is one month pregnant. She is prescribed Qnexa and her baby is born eight months later with a cleft palate. Perhaps her doctor didn’t keep abreast of the news: in February 2012 the FDA determined that Qnexa’s weight loss benefits for the chronically obese outweighed the risks of birth defects associated with the drug.

Same goes for Topamax. It has been linked to many adverse conditions, and in recent years to birth defects. In March 2011, the FDA reported that oral clefts in babies are 20 times more likely with women who used Topamax (topiramate) after getting pregnant. Perhaps your doctor doesn’t read every FDA drug warning. And perhaps the Topamax drug reps didn’t tell your doctor that the drug they are selling is linked to birth defects.

Also in March 2011, the FDA said that the prescribing information for Topamax and generic topiramate products would be changed to warn women and their doctors about an increased risk of oral cleft birth defects in children whose mothers used these epilepsy and migraine drugs during pregnancy. But three years before the FDA announcement, the journal Neurology (Nov 7, 2008) reported that exposure to Topamax in the first trimester of pregnancy carries a higher-than-usual rate of congenital malformations. How many doctors have time to read every medical journal?

It gets even more complicated for doctors. Topamax, originally approved to treat epilepsy seizures, is often prescribed “off-label” for weight loss, chronic pain, headaches, alcoholism, bulimia and psychiatric conditions. Off-label use of medications is not illegal. A drug company is allowed to market its drugs for uses that are part of the warning label and for indications for which the FDA has approved the drug - once it has reviewed available safety data. However, many pharmaceutical manufacturers have failed to provide adequate safety information, and many physicians are unaware of the lack of safety data to support a number of off-label uses of medications, which has resulted in harm to patients and, in the case of Topamax, their babies.

Topamax is an Ortho-McNeil and Johnson & Johnson product. Generic versions of Topamax, known generally as topiramate, are sold by Teva Pharmaceuticals, Watson Pharmaceuticals and Mylan, as well as other generic drug companies.