TUESDAY, Sept. 27 (HealthDay News) -- Even though off-label use of atypical antipsychotic drugs is common, a new review finds that such use is only effective in a few conditions and can be harmful in others.

Also known as "second-generation" antipsychotics, these drugs are approved in the United States for treatment of schizophrenia, bipolar disorder and depression. But off-label use -- or use not approved by the U.S. Food and Drug Administration -- of these drugs to treat a number of other conditions is growing.

Researchers analyzed findings from 393 clinical studies to gauge effectiveness and uncover harmful side effects when Risperdal, Zyprexa, Seroquel, Abilify, Geodon, Saphris, Fanapt and Invega were used outside of FDA-approved indications.

Off-label use included treatment for behavioral symptoms in dementia, anxiety, depression, obsessive-compulsive disorder, eating disorders, post-traumatic stress disorder, insomnia, personality disorders and substance abuse.

The investigators found that Abilify (aripiprazole), Zyprexa (olanzapine) and Risperdal (risperidone) were associated with small but statistically significant benefits for elderly people with dementia symptoms, such as aggression, psychosis and mood changes.

Seroquel (quetiapine) was 26 percent more effective than placebo in people with generalized anxiety disorder, and Risperdal was four times more effective than placebo in people with obsessive-compulsive disorder.

There was no evidence that atypical antipsychotics benefited people with substance abuse or eating disorders, according to Dr. Alicia Ruelaz Maher, of RAND Health in Santa Monica, Calif., and colleagues.

The researchers also found that certain atypical antipsychotics increased the risk of death, stroke, movement disorders and urinary tract symptoms in elderly patients. In younger patients, some of the drugs caused problems such as weight gain, fatigue, sedation, and akathisia, also known as restless leg syndrome.

The study is published in the Sept. 28 issue of the Journal of the American Medical Association.

"The benefits and harms vary among atypical antipsychotic medications for off-label use," the researchers concluded in a journal news release. "This evidence should prove useful for clinicians considering off-label prescribing of atypical antipsychotic medications, and should contribute to optimal treatment decision making for individual patients with specific clinical symptoms and unique risk profiles."

More information

The U.S. National Institute of Mental Health has more about mental health medications.