Somatotropin is secreted by the anterior pituitary gland, which is located in the brain. Somatotropin is released in pulses during the first phases of sleep. The hormone is secreted "in response to positive and negative signals from the hypothalamus." Human growth hormone is also secreted during "weight training and resistance exercises."

The process of aging is now thought of as a disease instead of a natural process. As the graph on the right shows, the level of hGH in the body peaks when a person hits puberty. Afterwards, the level of hGH decreases as the person becomes older. In fact, after the age of 30, the levels of hGH begin to drop at a rate of 14% per decade. It has been found that at the age of 60, a person might only secrete 25% of the amount of hGH secreted when the person was 20. The level of hGH peaks when a person hits puberty. Afterwards, the level of hGH decreases as the person becomes older.

Human growth hormone treatment used to be an expensive treatment that only the rich could afford. When scientists found ways to make somatotropin in the 1980's, the price of somatotropin treatment was able to drop dramatically. Human growth hormone was originally obtained from cadavers (dead people), however, because there was a low abundance of available hGH, this forced the cost of hGH treatment to be astonomically high. After scientists discovered a way to produce hGH, the hormone was no longer taken from cadavers because of many purity issues. Even though the treatment was expensive, it was not guaranteed to be safe. Several growth hormone deficient children receiving hGH treatment got Jacob Creutzfeldt disease, which is a "fatal neurodegenative disorder" after receiving growth hormone from cadavers. Another form of treatment for somatotropin deficiency was found to be through secretagogues, which are other hormones and chemicals in the body that aid in the release of somatotropin. Secretagogues such as growth hormone releasing hormone help the pituitary gland release more somatotropin in the people who have somatotropin in their bodies but have difficulties releasing it.

There are many ethical issues surrounding the use of somatotropin. Since somatotropin is an enhancement drug (builds muscle mass), many athletes have found human growth hormone to be useful. At the Olympics in Sidney, Australia, somatotropin was widely used as a steroid. Athletes that use the drug were able to pass the drug tests because somatotropin is fairly new and tests to detect it have not been made yet. However, at the next Olympics in 2002, the IOC (International Olympic Committee) will be able to detect the use of somatotropin in athletes.