ADELPHI, Md. - Advisers to the Food and Drug Administration said yesterday that three blockbuster psychiatric drugs appear safe and effective for children and adolescents, despite side effects that can increase the risk of diabetes.

The FDA's panel of psychiatric experts voted to approve the use of drugs from AstraZeneca, Eli Lilly and Pfizer for treating schizophrenia and bipolar disorder in patients ages 10 to 17.

The FDA is not required to accept the group's advice, though it usually does.

"We'll take all of this into consideration, but I can't make any promises about when we'll take action," said Dr. Thomas Laughren, FDA's director of psychiatric drugs.

All three drugs already are approved for adults with schizophrenia and bipolar disorder. Their side effects include weight gain, high blood sugar and sleepiness.

A positive FDA decision will expand the use of drugs that already make up the top-selling class of prescriptions in the U.S., with 2008 sales of $14.6 billion, according to health care analysis firm IMS Health.

The panel - mainly comprised of psychiatrists - largely brushed aside concerns from patient and consumer advocates that the companies should have been required to conduct longer studies of the drugs' side effects.

The panel voted 11-4, with four abstentions, that Lilly's drug Zyprexa is safe for treating bipolar, despite evidence the drug causes significantly more weight gain than other treatments.

The Indianapolis-based company is seeking approval for the drug only as a second-choice, after other drugs have been tried.

"I had concerns about the metabolic side effects but if this is going to be used as the last treatment option then I think having other treatments available to physicians is worthwhile," said Dr. Frank Greenway, of Pennington Biomedical Research Center in Baton Rouge, La.

On the first day of the two-day meeting, more than a half-dozen nonprofit groups complained about the short length of the studies submitted to the FDA.

The studies averaged between four and six weeks in length.

"Schizophrenia and bipolar disorder last for decades, often for life, and treatment is needed during all those years," said Dr. Diana Zuckerman of the Research Center for Women and Families in Washington.

"These studies provide almost no useful information about long-term adverse reactions." *