According to the FDA, this new warning on July 1, 2005 was in response to recent studies that point to the possibility of an increased risk of suicidal behavior in adults taking antidepressants.

The FDA has requested all drug manufacturers to submit data from studies involving adults to see if antidepressants cause more suicides in patients who take them than in those who don't. The agency said it was in the process of reviewing data from drug manufacturers to determine the extent and seriousness of the risk. A review that they said could take more than a year.

Much of the concern over suicide and antidepressants has focused on children who use the drugs. A year ago, the FDA issued a warning that adults also may be at increased risk. There are concerns that antidepressants may cause agitation, anxiety and hostility, suicide, violence, psychosis, abnormal bleeding and brain tumors. The agency began reanalyzing hundreds of studies of the drugs to try to determine if that's the case. They also told the drug makers to add or strengthen suicide-related warnings on their labels in the meantime.

Those revised labels applied to both pediatric and adult usage of bupropion (Wellbutrin), citalopram (Celexa), fluoxetine (Prozac), fluvoxamine (Luvox), mirtazapine (Remeron), nefazodone (Serzone), paroxetine (Paxil), sertraline (Zoloft), escitalopram (Lexapro), and venlafaxine (Effexor).

Since then, several new studies have been published in medical journals about a possible suicide/antidepressant connection. Citing them, the FDA issued a new public health advisory cautioning doctors and patients to watch closely for worsening of depression or suicidal thinking. A health care professional should evaluate those who worsen. Close monitoring is particularly important soon after a patient starts taking antidepressants and after a dosage change.

On the same day of the new warning, the FDA also updated its web site with a notice about a “higher than expected” rate of suicide attempts in research with the nation's newest antidepressant, Eli Lilly's Cymbalta. The new information about Cymbalta was just the first in a series of updates the FDA has planned for antidepressant drugs, which include Zoloft, Paxil, Prozac and others. "The FDA is evaluating additional data to determine the relationship, if any, between suicidality and Cymbalta use," the FDA wrote in an alert to health-care professionals.

In February, the British Medical Journal published three studies that came to conflicting conclusions about the risks of suicidal behavior associated with antidepressants that are part of a class of drugs called selective serotonin reuptake inhibitors (SSRIs).One of these studies, with around 88,000 participants enrolled in 702 clinical trials, found a "significant increase in the odds of suicide attempts," which were found to be twice as likely in people taking SSRIs than in those taking a placebo.

Also, another study reported in the British Medical Journal claims that "the odds ratios for ischaemic heart disease were significantly raised for patients who had ever received a prescription for tricyclic antidepressants even after diabetes, hypertension, smoking, body mass index, and use of selective serotonin reuptake inhibitors had been adjusted for."

"The clinical implications are that we have good evidence that there is a rare but serious risk associated with SSRIs," said study author Dean Fergusson, a scientist at the Ottawa Health Research Institute in Ontario, Canada. "This information needs to be relayed to physicians and patients."

"In many ways we should be happy about this, because it shows the complexity of depression, and this cavalier giving of antidepressants to people may not be the best thing," Dr. C. Barr Taylor, director of the Laboratory for the Study of Behavioral Medicine at Stanford University Medical Center, said.

Parts of this article provided by The Associated Press;
The Indianapolis Star, July 5, 2005 and ScoutNews, LLC 2005