MONDAY, Aug. 19 (HealthDay News) -- One-fifth of U.S. neurologists are unaware of serious safety risks associated with epilepsy drugs and are potentially risking the health of patients who could be treated with safer medications, a new study reveals.

The 505 neurologists who took part in the survey between March and July 2012 were asked if they knew about several epilepsy drugs' safety risks recently identified by the U.S. Food and Drug Administration.

These risks included increased danger of suicidal thoughts or behaviors linked with some newer drugs, a high risk for birth defects and mental impairment in children of mothers taking divalproex (brand name Depakote), and the likelihood of serious hypersensitivity reactions in some Asian patients treated with carbamazepine (Tegretol).

One in five of the neurologists said they did not know about any of these risks. Neurologists who treat 200 or more epilepsy patients per year were most likely to know all the risks, according to the study, which was published online recently in the journal Epilepsy.

Although this study focused on epilepsy drugs, the findings suggest that the FDA needs to find better ways to inform doctors about newly discovered drug safety risks, said the researchers from Johns Hopkins University School of Medicine. Their results show that warnings about these risks are not getting through to doctors making important prescribing decisions.

There is no single place for neurologists to find updated drug risk information, said study leader Dr. Gregory Krauss, a professor of neurology. A few get emails from the FDA, while others get the information from neurology societies, continuing medical education courses or journal articles.

"There is poor communication from the FDA to specialists, and there's some risk to patients because of this," Krauss said in a Johns Hopkins news release.

"Unless it's a major change requiring the FDA to issue a black box warning on a product, important information appears to be slipping through the cracks," he said. "We need a more systematic and comprehensive method so that doctors receive updated safety warnings in a format that guarantees they will see and digest what they need to protect patients."