Topamax and its generic versions - topiramate - taken during pregnancy, increase the likelihood of babies being born with cleft lip and cleft palate, new data suggests, the Food and Drug Administration (FDA), USA wrote in a communiqué today.
The FDA says that doctors should warn their female patients of childbearing age about the possible dangers to the fetus if they become pregnant while taking topiramate.
Topiramate is currently used for the treatment of epilepsy in adults and children. It was originally designed as an anticonvulsant. In children it is used to treat Lennox-Gastaut syndrome, a disorder causing seizures and developmental delay. It is also approved in the USA for the prevention of migraines (not for treating migraine pain). It has been used to treat bipolar disorder by psychiatrists - a Cochrane review in 2006 did not find enough evidence to back its use in any phase of bipolar disorder.
Russell Katz, M.D., director of the Division of Neurology Products in the FDA's Center for Drug Evaluation and Research, said:
"Health care professionals should carefully consider the benefits and risks of topiramate when prescribing it to women of childbearing age. Alternative medications that have a lower risk of birth defects should be considered."
Cleft lip is also known as cheiloschosis, while cleft palate is also known as palatoschisis. They are both types of abnormal developments of the face while the fetus is in the womb - they are types of clefting congenital deformities. In some cases, babies are born with both - cleft lip and palate. Before the baby is born, natural structures form in the body and fuse (join together). A cleft is when these structures do not fuse, there is a gap, also known as a fissure. When the gap occurs in the upper lip it is a cleft lip, in the roof of the mouth (palate) it is called a cleft palate. When both sides of the lip are affected it is called a bilateral cleft, just one side is a unilateral cleft.
Cleft lip and/or palate, also known collectively as oral clefts occur during the first trimester of pregnancy, when most women don't know they are pregnant. The baby can be born with a small notch in the lip to a gap that runs into the palate and nose, which may cause eating and talking problems, as well as ear infections. Surgery can be performed to close the lip and palate, usually successfully.
According to the North American Antiepileptic Drug Pregnancy Registry, there is a raised risk of cleft lip and/or palate in infants whose mothers took topiramate during the first three months of their pregnancy.
The risk of being born with a cleft lip and/or palate is:
- 1.4% among infants exposed to topiramate as a single therapy during their mother's pregnancy
- 0.38% to 0.55% for infants whose mothers took other antiepileptic drugs during their first trimester
- 0.07% for infants whose mothers did not have epilepsy and took no antiepileptic drugs
The FDA wrote yesterday that topiramate will have a stronger warning on its labeling.
"The pregnancy category will be changed to Pregnancy Category D. This means that there is positive evidence of human fetal risk based on human data, but the potential benefits of the drug in pregnant women may outweigh the risks in certain situations. The FDA previously designated the drug as Pregnancy Category C because of the lack of human data."
Pregnant mothers and females of childbearing age who are considering taking topiramate should talk to their doctors about alternative treatments.
A woman on topiramate who becomes pregnant or plans to do so should let her doctor know immediately.
Do not stop taking topiramate unless your doctor tells you to.
Those who become pregnant while on topiramate therapy should talk to their doctor about registering with the North American Antiepileptic Drug Pregnancy Registry.
Source: FDA, Medical News Today archives
Written by Christian Nordqvist