UPDATE 1-FDA handling of Lilly drug needs probe--scientist

(Recasts, adds comments, details)

WASHINGTON, Feb 13 (Reuters) - U.S. lawmakers should investigate the Food and Drug Administration's handling of side effects linked to Eli Lilly and Co.'s (LLY.N: Quote, Profile, Research, Stock Buzz) antipsychotic medication, Zyprexa, an agency whistleblower said on Tuesday.

FDA scientist Dr. David Graham told a congressional hearing the drugmaker and the agency knew "for a long time" about the risk of weight gain from Zyprexa that could trigger diabetes.

While such side effects were eventually added to the drug's prescribing instructions, Graham testified it was not clear how the agency handled the information or made the decision to alter the label.

"FDA did its typical dragging its feet on post-marketing safety issues," he told Reuters after the U.S. House of Representatives Energy and Commerce subcommittee hearing.

Graham did not review Zyprexa, but said that, after his 2004 public testimony criticizing the FDA's actions on Merck & Co Inc.'s (MRK.N: Quote, Profile, Research, Stock Buzz) withdrawn Vioxx painkiller, other agency staffers came to him with concerns.

Zyprexa, approved in 1996, is cleared to treat schizophrenia and bipolar disorder.

Other antipsychotic medications also warrant closer scrutiny, Graham told lawmakers without naming specific drugs. He also said he would submit a list of other types of prescription drugs with safety concerns that the committee should investigate.