WASHINGTON (AP) — Government inspectors told lawmakers Wednesday that Medicare officials need to do more to stop doctors from prescribing powerful psychiatric drugs to nursing home patients with dementia, an unapproved practice that has flourished despite repeated government warnings.

So-called antipsychotic drugs are designed to help control hallucinations, delusions and other abnormal behavior in people suffering from schizophrenia and bipolar disorder, but they're also given to hundreds of thousands of elderly nursing home patients in the U.S. to pacify aggressive behavior related to dementia. Drugs like AstraZeneca's Seroquel and Eli Lilly's Zyprexa are known for their sedative effect, often putting patients to sleep.

But the drugs can also increase the risk of death in seniors, prompting the Food and Drug Administration to issue multiple warnings against prescribing the drugs for dementia. Antipsychotics raise blood sugar and cholesterol, often resulting in weight gain.