Taking diet drug Acomplia (rimonabant) approximately doubles your risk of depression, and the risk may be even higher if you have a past history of depression, according to the European Medicines Agency (EMEA).

"This doubling of the risk of depression occurs in all types of patients," the EMEA's Committee for Medicinal Products for Human Use (CHMP) said in the most definitive statement to date quantifying the link between Acomplia and depressive side effects.

"This increased risk is of concern, since Acomplia is now being used in patients with a history of psychiatric events," said the CHMP. "In a small minority of cases, this could lead to suicidal ideation or even suicide attempts."

The CHMP reached the conclusions about the link between Acomplia and depression after analyzing a year's worth of data it requested from Sanofi on "the psychiatric safety of Acomplia, focusing on cases of depression in patients taking the medicine."

Sanofi provided data on the more than 100,000 patients who have taken Acomplia in Europe since it was approved for sale in the European Union.

In assessing the data, the CHMP said it concluded "that the benefits of Acomplia continue to outweigh its risks, except in patients with ongoing major depression or taking antidepressants."

But it expressed concern that "too many patients are taking Acomplia at the same time as antidepressants, even though Acomplia is not recommended for use in patients also taking antidepressants."

"Acomplia must no longer be used in these patients," the CHMP said in approving stiffer warnings to doctors not to prescribe Acomplia for depressed patients.

Meantime, regulators in the U.K. -- where more patients have taken Acomplia in the past year than any other country -- said evidence suggests one person in 10 experiences psychiatric side effects and about one person in 100 experiences suicidal thoughts while on the diet drug.

Of some 41,000 patients treated with rimonabant since it was launched in the U.K. in June 2006, 364 "psychiatric reactions have been reported," the Department of Health's Medicines and Healthcare Products Regulatory Agency (MHRA) said on July 19th.

"Amongst these, there have been 48 reports of depression, 16 reports of suicidal thoughts and one report of self-injury," the regulatory agency said.

The MHRA advised: "If you start to experience symptoms of depression while taking Acomplia, or if you are currently being treated with antidepressants, consult your doctor.

"If you have had depression in the past but feel well on Acomplia, you should continue treatment with Acomplia and discuss your treatment with your doctor at your next routine appointment."