ADELPHI, Md. (AP) — Advisers to the FDA say a powerful psychiatric drug from AstraZeneca is safe and effective to treat schizophrenia in adolescents. The FDA’s panel of experts voted overwhelmingly that the pill Seroquel is a useful treatment for schizophrenia in patients ages 13 to 17. A vote on the drug’s use for pediatric bipolar disorder is slated for later Wednesday. The group also is weighing expanded approval of drugs from Eli Lilly and Pfizer for schizophrenia and bipolar disorder. The FDA is not required to follow the group’s advice, though it usually does. A positive FDA decision would allow the companies to expand marketing of drugs that already make up the top-selling class of prescriptions in the U.S.