WASHINGTON – Drugs used to treat epileptic seizures can raise suicide risks, but not enough to deserve the strongest warning labels available, a government panel of experts said Thursday.

Advisers to the Food and Drug Administration voted 14-4 against adding a “black box” warning about the risks of suicidal tendencies to all anti-seizure drugs.

The FDA earlier this week announced plans to add boxed warnings to epilepsy drugs, in light of an analysis of suicidal tendencies of more than 43,000 patients enrolled in 200 studies. The panel vote makes it less likely that blockbuster drugs from GlaxoSmithKline, Pfizer Inc., Merck & Co. Inc. and others, will be forced to carry the FDA's sternest warning.

The agency often follows its panels' advice, though it is not required to do so.

The panel's vote broke down along professional lines, with psychiatrists and neurologists voting against adding a black box, and statisticians favoring the warnings.

The agency announced earlier this year that patients taking 11 widely used anti-seizure drugs were more likely to have suicidal thoughts and behaviors than those taking dummy pills. While the reported problems were extremely rare, the FDA said drug-treated patients did face about twice the risk.

In an earlier vote, panelists unanimously backed FDA findings that those drugs can increase suicidal tendencies in patients.

More than 10 million Americans take the 25 medications discussed at the FDA's meeting. Besides epilepsy they are also used for migraines, certain nerve-pain disorders, and psychiatric diseases such as bipolar disorder.