Doctors in Sutton and Merton wrote 172,000 prescriptions for anti-depressants as patients sought to lift their mood during the recession.

New figures show NHS officials spent £1.5m on drugs such as Prozac last year, the highest bill reported by 31 London primary care trusts.

The total contrasts with a £558,089 bill for Kensington, and Chelsea and comes despite reductions in the cost of pills under a Government scheme.

Mental health charities emphasised that anti-depressants were only a quick fix for patients struggling to cope with the stresses of the recession.

But Sutton and Merton PCT claimed it may have outspent other trusts simply because its doctors operated in two london boroughs.

A spokeswoman said: “The trust covers more than 400,000 residents, so the statistics may not be comparable with other PCTs, which cover only one borough.

“We will be studying the new report to look at the findings.

“The PCT is investing over £2.4m to increase mental health therapy services in our area to ensure patients get faster access to the care they need closer to home.

"It is hoped we will improve the health of our residents by giving them treatment earlier to prevent more serious conditions.”

Less than six months ago the trust won praise from the Mental Health Foundation for minimising volumes of prescribed drugs.

Dr Andrew McCulloch, chief executive of the charity, said: “People should be offered a range of treatment options for depression and other common mental health problems, not just anti-depressants, which can have unpleasant side effects for some people.”

The figures from the NHS Information Centre showed the number of prescriptions issued across the capital rose by 188,252 to 3.27m in the 12 months to April.

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