People taking the weight-loss drug rimonabant have an increased risk of mental health problems, according to a study of more than 4,000 patients in four clinical trials. Those taking the drug were 40% more likely to suffer conditions such as depression and anxiety than people taking a placebo.
The drug, sold in the UK under the name Acomplia by pharmaceutical company Sanofi-Aventis, has already been linked to potential psychiatric problems. In July, the European medicines agency warned rimonabant could be unsafe for patients taking antidepressants. Reactions to rimonabant reported to Britain's drug regulator, the Medicines and Healthcare Products Regulatory Agency, include depression and suicidal thoughts.
In America, drug regulators decided against approving the drug for sale because of concerns over increased suicide risk.
In the latest study, published today in the Lancet, Arne Astrup at the University of Copenhagen led a team that looked at trial data on how effective a 20mg daily dose of rimonabant was compared with a dummy pill.
They found that patients taking rimonabant lost, on average, 4.7kg more weight after one year than those given the placebo. However, they were three times more likely to stop treatment because of anxiety and 2.5 times more likely to stop because of depression.
"Taken together with the recent US food and drug administration finding of increased risk of suicide, we recommend increased alertness by physicians to those potentially severe psychiatric adverse reactions," Astrup wrote.
A spokesperson for Sanofi-Aventis said the Lancet study did not introduce information that it, doctors and regulatory bodies had not already considered and acted upon. "The authors highlight that it is important to understand that patients who have been depressed are at risk from further episodes, and should therefore not be prescribed the product."
