Specialists are reporting a dramatic rise in the use of human growth hormone (HGH), a fast-acting chemical commonly used by bodybuilders and other people wanting to build up muscle or self-esteem.

Increased use of the drugs, which carry serious health risks including heart failure, has been attributed to cheap imports from China and the US flooding the market.

They are sold via thousands of unregulated websites that lure clients with the unlikely promise of instant results.

HGH is produced naturally in the pituitary gland to stimulate growth through protein synthesis. It also regenerates muscle, repairs tissue, strengthens bones, cuts fat and supplies energy.

Taking growth hormone, which is a prescription drug, is not against the law, but it is illegal to distribute it.

However, senior police and customs sources told The Times that extensive investigations into Class-A drugs, such as cocaine, had left neither the money nor the manpower to stem the trade in HGH.

In one needle exchange in Merseyside and Cheshire alone, half the syringes are being used for steroids and growth hormones and half for heroin, according to Pat Lenehan, a steroids expert who started the Drugs and Sport Information Service. Rob Dawson, who runs an advisory clinic specialising in performance-enhancing drugs, said that the use of HGH had “gone ballistic” in the past four months.

Having fielded a handful of inquiries about growth hormone in ten years, now he sees at least two people a week who have started to use the drug.

At £30 for a four-unit dose, normally injected twice daily, HGH had proved too expensive for many people, but cheap imports have pushed down the cost to as little as £10 a day. It is not known what proportion of the drugs are fakes.

Dr Dawson, who is based in Chester-le-Street, Co Durham, said that the growing number of people visiting specialists for HGH advice was “clearly just the tip of the iceberg”.

People are seemingly unaware of the risks attached, including acromegaly, in which soft tissue and internal organs become swollen and the brow and jaw grow abnormally large. In the worst cases, the condition causes causes diabetes and heart failure.

Dr Dawson said that he was very concerned. “In the past few months the requests for information about growth hormone have gone absolutely ballistic. These drugs were prohibitively expensive, but now a lot of people can afford them.

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