Pituitary gland present in the brain secretes the human growth hormone (HGH). Human growth hormone helps in regulating development and growth. So, it is a very essential hormone. This hormone helps in normal growth of children, and helps in metabolism in the adults. Many research and studies have shown that high growth hormone is also helpful for AIDS patients in reversing muscle wasting. Also, it delays the ageing process as claimed by doctors. Earlier, when genetic engineering was not introduced, Human growth hormone was produced artificially by the removal of the pituitary gland present in cadavers. But now by the advancement of the science and introduction of genetic engineering, synthetic or artificial HGH is produced by the use of live cell culture. But, this is very expensive and complex manufacturing process. So, HGH injections that are available in market are expensive.
Children with pituitary gland does not releasing enough amount of growth hormones are provided with synthetic HGH. Adults too can be given HGH if they have problem with pituitary gland. These hormones are taken by the athletes to improve their growth of muscle and enhance the stamina. Many of the claims given by the manufacturers are not right. If HGH is taken in excess and without supervision, it can lead to side effects.