The hormone should be used only for genuine medical reasons such as growth disorders or dwarfism. It is subsidised on the Pharmaceutical Benefits Scheme only for such conditions, but parents with healthy children are rorting the system. Professor Ken Ho, chairman of the department of endocrinology at St Vincent's Hospital, said he knew of numerous short children with normal hormone levels who had been given HGH to boost height.

"People increasingly want their kids to be taller, stronger, more beautiful than somebody else's and that's why growth hormones are being sought out," he said. "Parents don't want their children to be the shortest in the class. I see a lot of parents who see me for a second opinion about the risks and benefits of this treatment and I tell them their child does not need this." Two prominent Melbourne hormone specialists confirmed the trend and said unscrupulous doctors were also spruiking the drug to parents who viewed shortness as a "social disadvantage". Professor Ho - who said he had been "inundated" with anxious parents given the drug for their children without good reason - warned misuse could have serious side effects. "Long-term use can lead to disfiguration of the body because it stimulates the growth of all tissues, including bone," he said.

The revelations come after a Sun-Herald investigation last week revealed the drug is being widely prescribed by anti-ageing clinics to middle-aged men who want to look and feel younger. Human growth hormone is released by the brain's pituitary gland and promotes growth during adolescence. The synthetic form of the hormone must be injected daily and costs up to $200 a week.

Professor George Werther, a pediatric endocrinologist at the Royal Children's Hospital in Melbourne, said: "The average short kid with short parents may only gain three or four centimetres. That equates to about $30,000 for each centimetre, which is a lot of taxpayers' money for something fairly questionable." He said the hospital provided counselling for families and children affected by short stature. The head of the Australian Childhood Foundation, Joe Tucci, said parents who used human growth hormone to make healthy children taller could cause psychological and physical harm.

"It gives the child the perception that if they're short they're not as good as other children," he said.