Growth hormone therapy is the use of human growth hormone to induce growth in patients of abnormally low stature or for other medical reasons. Usually, growth hormone therapy is used to treat deficiencies in growth hormone, but it can also be used to treat other conditions resulting in small stature. It has also been used to treat acquired immune deficiency syndrome (AIDS), obesity, large burns, and, controversially, to slow the aging process and to increase athletic performance.
Human growth hormone is naturally produced in healthy people by the pituitary gland at the base of the brain. It is responsible for normal growth and cell reproduction. If the pituitary does not produce enough growth hormone, a person will not grow to full adult height. Growth hormone therapy is most commonly used in children with a growth hormone deficiency. While growth hormone for therapeutic purposes was once extracted from human pituitary glands, it is now synthesized through recombinant technology, in which human genes are inserted in bacteria, which then produce the hormone.
In addition to human growth hormone deficiency, conditions characterized by inadequate growth that have been treated with growth hormone therapy include chromosomal disorders like Turner syndrome, Noonan syndrome, and Prader-Willi syndrome; intrauterine growth retardation, or low birth weight; idiopathic short stature, or unexplained failure to grow to normal height; and short stature caused by chronic renal failure. Post-transplant growth failure, rickets, growth impairment due to inflammatory bowel disease, and coeliac disease have also benefited from growth hormone therapy in addition to more traditional treatments.
More controversially, growth hormone therapy has been used to slow the normal aging process and to boost athletic performance and increase muscle mass. It has not been proven that growth hormone therapy is helpful for such goals, and there are numerous side effects associated with such uses. These include edema or fluid retention, joint pain, carpal tunnel syndrome, high blood pressure, diabetes, and gynomastica, the enlargement of mammary glands in males.
Growth hormone therapy for children is not associated with as many side effects and is considered relatively safe. Though side effects are rare in children, they are potentially serious. Some of the same side effects experienced by adults, including edema, joint pain, and carpal tunnel syndrome, can effect children undergoing growth hormone therapy, but at a much lower probability. One side effect particular to children is slipped capital femoral epiphysis (SCFE), in which the head of the femur, or thigh bone, becomes separated from the shaft, causing hip pain. Pseudotumor cerebri (PTC), a neurological disorder causing headaches, nausea, and visual abnormalities, occurs in about one in 100 cases of pediatric growth hormone therapy, but discontinuation of the therapy usually reverses the condition.