The role of human growth hormone in your body
Human growth hormone (hGH or GH)—also known as somatotropin—is a protein that is important not only during childhood growth but throughout adulthood. It is produced by the pituitary gland, which is also known as the "master gland" because it secretes many hormones that control the actions of other glands. A part of the brain called the hypothalamus sends signals to the pituitary gland to produce growth hormone, which then travels through the bloodstream to function in other parts of the body.
Scientific research usually focuses on the role of growth hormone in the growth process, but its contribution to adult metabolic processes (the physical and chemical body processes that maintain life) is also crucial.
Learn more about how human growth hormone works by viewing an animation now.
Growth hormone and growth
Growth is affected by more than hormones. Good nutrition and a child's general health are important factors in normal growth.Likewise, growth hormone isn't the only hormone that affects the growth process. Other pituitary hormones—thyroid-stimulating hormone, adrenocorticotropic hormone, luteinizing hormone, and follicle-stimulating hormone—affect growth indirectly by acting through other glands. Although many hormones can influence growth, GH is the major growth regulator in the body.
The primary job of growth hormone is to cause bones and other body tissues to grow. For bone growth, it directly stimulates the areas of bones known as epiphyseal growth plates, which are responsible for bone elongation. In addition to stimulating growth, growth hormone also causes growth indirectly by triggering the release of a protein called insulin-like growth factor-I (IGF-I) from tissues throughout the body. IGF-I stimulates the growth of bone, muscle, and other body tissues in response to growth hormone and, in turn, regulates GH release from the pituitary gland. Growth hormone also contributes to proper bone density. This mechanism, in conjunction with other complex body processes, maintains growth from infancy through adulthood.
Growth hormone and metabolism
The importance of growth hormone doesn't diminish once adulthood is reached and bone growth stops. Growth hormone also helps regulate metabolism (the chemical processes by which the body turns food into energy, tissue, or waste products) in a number of ways—transporting molecules, conserving sugars, building proteins (including muscles), and breaking down fats. Not only is it vital to maintaining healthy body composition, it also contributes to proper bone density, and ratios of "good" to "bad" cholesterol.
Growth hormone deficiency
When the body doesn't make enough growth hormone to keep a child's bones growing at the proper rate, a condition known as pediatric growth hormone deficiency (PGHD) results. When an adult doesn't produce enough growth hormone, he or she has adult growth hormone deficiency (AGHD).
References
Guyton AC, Hall JE. Textbook of Medical Physiology. 9th ed. Philadelphia, Pa: WB Saunders; 1996.Lifshitz F, ed. Pediatric Endocrinology. 4th ed. New York, NY: Marcel Dekker Inc; 2003.
Nutropin AQ [product monograph]. South San Francisco, Calif: Genentech Inc; 2002.
Wilson JD, Foster DW, Kronenberg HM, Larsen PR, eds. Williams Textbook of Endocrinology. 9th ed. Philadelphia, Pa: WB Saunders; 1998.
WHO IS NUTROPIN FOR?
Nutropin® [somatropin (rDNA origin) for injection] and Nutropin AQ® [somatropin (rDNA origin) injection] are human growth hormone, available by prescription only.
Doctors prescribe Nutropin for children and teenagers with growth failure who:
- do not make enough growth hormone on their own
- have chronic renal insufficiency—a slow loss of kidney function—and have not had a transplant
- have Turner syndrome
- are not likely to grow to their potential adult height, as determined by a doctor, and whose bones are still able to grow
Doctors prescribe Nutropin for adults who:
- have growth hormone deficiency that started either in childhood or as an adult due to brain surgery, radiation therapy, trauma, or diseases of the pituitary gland or the hypothalamus.
Your doctor will test to see if growth hormone is right for you.
IMPORTANT SAFETY INFORMATION
Nutropin and your safety:
Please read this important safety information carefully. Then, if you have any questions, talk with your doctor.
Nutropin is NOT for:
- children and teenagers whose bones have finished growing
- patients who have certain types of eye disease caused by diabetes
- patients who have active cancer or any brain tumors
- patients who are critically ill after open heart surgery or abdominal (stomach) surgery, are severely hurt, or have severe breathing problems
- children and teenagers who have Prader-Willi syndrome and are very overweight or have trouble breathing
If any of these apply, talk to your doctor before you start taking Nutropin.
If you are about to start taking Nutropin, or are already taking it, be sure to tell the doctor who prescribed it:
- about ALL of the medications you are taking, including supplements
- if you have or develop a brain tumor
- if you are given any new medication—especially cortisone, hydrocortisone, prednisone, prednisolone, dexamethasone, triamcinolone, or betamethasone
- if you are pregnant or if you become pregnant
- about ANY other condition or illness you have or develop
What are the possible side effects of Nutropin?
As with any injection you may experience discomfort, soreness, or redness where Nutropin is injected.
Contact your doctor immediately if you experience:
- ongoing injection site discomfort
- curvature of the spine (scoliosis)
- joint pain
- puffy hands and/or feet (caused by fluid retention)
- changes in vision, a bad headache, or nausea with or without vomiting
- hip or knee pain
- a need to limp when you walk
- pain in wrist (carpel tunnel)
- allergic reaction
Be sure to inject Nutropin at a different recommended place on your body each time. Your doctor or nurse should supervise the first injection and provide training and instruction.
Your doctor is your primary source of information about your treatment.
Please see the full Prescribing Information, also available from your pharmacy.
