ADELPHI, Md. — Federal health advisers delivered a split opinion Wednesday on whether to withdraw the diet pill Meridia because of evidence it increases heart attack and stroke, with half voting to ban it and the others favoring new warnings and restricted distribution.

A panel of Food and Drug Administration advisers voted 8-8 on whether to allow continued marketing of the drug by drugmaker Abbott Laboratories. Earlier this year, European regulators banned the drug after the safety issues were raised.

Meridia has been sold since 1997, but data released in November showed patients with pre-existing heart disease were more likely to suffer traumatic heart attacks and strokes than patients taking a dummy pill. European regulators withdrew the drug in January based on the results, but the FDA wanted to seek the input of its advisers before making a decision.

Meridia is one of only three prescription drugs currently approved for weight loss.

The drug's benefits and risks present the FDA with a classic drug safety choice: whether to try to limit the use of the drug to patients who are likely to benefit, or recall it from the market and prevent any harm.

The agency is not required to follow the group's advice, and deputy director Dr. Eric Coleman offered little insight into how the FDA would interpret the panel's split vote.