Deaths involving overdoses of antidepressants such as Prozac and Seroxat have more than doubled in five years.

Deaths involving overdoses of antidepressants such as Prozac and Seroxat have more than doubled in five years.

Doctors and mental health campaigners warned that over-prescribing, coupled with a lack of accurate research into their risks, was fuelling the rise in the number of people who have committed suicide as a result of taking pills which are supposed to alleviate depression.

More than 3.5 million people in Britain received 20 million prescriptions for selective serotonin reuptake inhibitors (SSRIs) last year. But concerns about the safety of the drugs have increased after reports that some patients who only suffered from mild depression had committed suicide within days or weeks of being prescribed the pills.

In 1999, 38 people died as a result of SSRI overdoses, according to Health Statistics Quarterly, published yesterday by the Office for National Statistics (ONS). By 2003, this had more than doubled to 81.

Because one of the advantages of SSRIs is their low toxicity level, most of these deaths are considered to be deliberate overdoses. Still more people - at least eight in the UK in the past two years - have killed themselves by other means, such as hanging, after being prescribed the SSRIs.

The government-run Medicines and Healthcare products Regulatory Agency (MHRA), ruled last December that, for adults, the benefits of SSRIs outweighed the risks. But the controversy has highlighted how doctors, patients and regulators such as the MHRA are reliant on information supplied by the drugs companies making the drugs.

GlaxoSmithKline, which makes Seroxat, is under investigation for withholding safety data on the drug and only publishing favourable results from clinical trials.

Richard Brook, chief executive of the mental health charity Mind, said: "I think these figures are very worrying ... the way in which SSRIs contribute to suicides has yet to be understood. We haven't got all the data because we haven't had proper follow-up studies, post-licensing procedures are poor and, most of all, we still have to rely on the drugs companies to supply the data, whose record on this issue is deplorable."