MONDAY, Feb. 6 (HealthDay News) -- Antidepressant drugs such as Prozac do not raise suicide risk in young people, a new study says.

The finding should help reassure doctors about prescribing antidepressants to youngsters, said first author Robert Gibbons, a professor of medicine, health studies and psychiatry at the University of Chicago.

In 2004, the U.S. Food and Drug Administration ordered a "black box warning" for Prozac (generic name fluoxetine) after data from 25 clinical trials suggested the medications increased the risk of suicidal thoughts and behaviors in children and young adults up to age 25.

But this analysis of data from 41 clinical trials involving a total of more than 9,000 patients identified no such link in either adults or children.

"I hope that the [black box] warnings will not prevent depressed children and adults from getting treatment for depression," Gibbons said in a university news release.

One expert agreed. Dr. Mark Russ, director of psychiatric services at Zucker Hillside Hospital in Glen Oaks, N.Y., said the study "argues that treatment with the antidepressant medications examined ... is not associated with a higher risk of suicidal ideation and behavior, and should not be withheld for this reason."

The study also found that Prozac and another antidepressant called Effexor (venlafaxine) reduced suicidal behavior and depression in adults and seniors.

For their study, Gibbons and colleagues used clinical trial data -- some of it unpublished -- from drug makers and a large U.S. National Institute of Mental Health collaborative study of Prozac and Effexor. The study -- funded by the U.S. National Institute of Mental Health and the U.S. Agency for Healthcare Research and Quality -- appears online Feb. 6 in the journal Archives of General Psychiatry.

To assess the effects of antidepressants in children, the researchers examined four trials of Prozac. Until recently, it was the only antidepressant approved for use in children, according to a University of Chicago Medical Center news release.

The studies showed that the drug reduced depression symptoms in children and did not have any effect on their suicide risk.

The results from the trials of Prozac and Effexor in adults and seniors found that the drugs reduced both depression symptoms and suicide risk. This suggests that antidepressants cut the suicide risk in adults and seniors by easing patients' depression, the news release said.

"I think that this paper supports the general idea that the effects of antidepressants in kids and adults are not really the same, since we don't see anything but beneficial effects of antidepressants in adults and geriatrics," Gibbons said in the release. "In kids, we don't see a harmful effect, but we do see a disassociation between the beneficial effects on depression and the potential beneficial effect on suicide."

He added: "This raises continued questions about what's going on in children. Maybe children think about suicide in part because of depression, but also maybe due to other reasons not related to depression that are not affected by antidepressants."

One expert welcomed the study findings.

"This very important study goes a long way to undoing what I consider an ill-conceived FDA issued black box warning for antidepressants and risk of suicide in children and adolescents," said Dr. Norman Sussman, a psychiatrist at NYU Medical Center in New York City. "It was a finding of an increased rate of ideation [suicidal thoughts] and attempts during some clinical trials that formed the entire basis for the FDA black box warning. Yet, as the authors of the current paper point out, no actual suicides occurred in these [trials]."

According to Sussman, who is also professor of psychiatry at NYU School of Medicine, the warning led to a drop in antidepressant prescriptions for depressed children. "In what I hope will lead to a corrective series advisories that encourage antidepressant use, the results of this study confirm what clinicians have observed all along, namely, treatment with antidepressants decreases suicide risk," he said.

Gibbons agreed. "The greatest cause of suicide is untreated or undiagnosed depression," he said. "It's very important that this condition be recognized and appropriately treated and not discarded because doctors are afraid to be sued."

More information

The Nemours Foundation has more about children and depression.