Growth hormone therapy is a medically approved treatment for children and adults with growth hormone deficiency and select endocrine disorders. Recombinant human growth hormone has transformed pediatric endocrinology and adult metabolic care, offering measurable benefits when prescribed appropriately. However, its indications, mechanism of action, risks, and misuse are often misunderstood. This article reviews how growth hormone therapy works, what it treats, and when referral to a specialist is necessary.

What is Growth Hormone?

Growth hormone, also called human growth hormone (HGH) or somatotropin, is a peptide hormone produced by the anterior pituitary gland. It plays a central role in: 

  • Linear growth in children 
  • Muscle and bone development 
  • Lipid and carbohydrate metabolism 
  • Regulation of body composition 

What triggers human growth hormone (HGH)?

HGH secretion is pulsatile and influenced by: 

  • Growth hormone–releasing hormone (GHRH) 
  • Sleep, particularly deep sleep 
  • Physical activity 
  • Hypoglycemia 
  • Puberty 

Somatostatin inhibits GH release, while insulin-like growth factor 1 (IGF-1) provides negative feedback regulation. 

What is the function of human growth hormone (HGH)?

HGH stimulates: 

  • Liver production of IGF-1 
  • Protein synthesis 
  • Lipolysis 
  • Linear bone growth in children 
  • Lean body mass maintenance in adults 

What is Growth Hormone Therapy? 

Growth hormone replacement therapy involves administering recombinant human growth hormone (rhGH) through subcutaneous injection. It is used when endogenous production is insufficient or when specific syndromes impair growth. 

This therapy is not the same as anti-aging or performance-enhancement use, which falls outside medical guidelines. 

What do growth hormone medications treat? 

FDA-approved uses of human growth hormone therapy include: 

  • Pediatric growth hormone deficiency 
  • Turner syndrome 
  • Prader-Willi syndrome 
  • Chronic kidney disease with growth failure 
  • Small for gestational age without catch-up growth 
  • Adult growth hormone deficiency 

Growth hormone therapy for adults may improve body composition, bone density, and quality of life in confirmed deficiency states. 

How was growth hormone therapy invented? 

Early GH therapy in the 1950s used cadaver-derived pituitary extracts. Due to safety concerns including Creutzfeldt-Jakob disease transmission, this method was discontinued. 

In 1985, recombinant DNA technology enabled the production of synthetic human growth hormone, making growth hormone therapy safer and widely accessible.  

What are normal levels of human growth hormone (HGH)? 

HGH levels vary by age and testing method. Because GH is released in pulses, random measurements are unreliable.

Diagnosis typically involves: 

  • Stimulation testing 
  • IGF-1 level measurement 
  • Clinical growth assessment 

Normal IGF-1 ranges vary by age and laboratory standards.

Mechanism of Action – How does growth hormone therapy work? 

It increases circulating IGF-1 levels. IGF-1 mediates many anabolic effects including: 

  • Stimulation of chondrocytes in growth plates 
  • Increased protein synthesis 
  • Enhanced lipolysis 
  • Reduced fat mass

In adults with GH deficiency, therapy improves lean body mass and metabolic parameters.

What are the risks of growth hormone therapy?

When prescribed appropriately, GH therapy is generally safe. However, potential risks include: 

  • Fluid retention 
  • Arthralgia 
  • Insulin resistance 
  • Increased intracranial pressure (rare) 
  • Slipped capital femoral epiphysis in children 

Monitoring is essential to minimize complications. 

What are the potential harms of inappropriate use of growth hormone therapy? 

Non-medical use of GH can lead to: 

  • Acromegaly-like changes 
  • Cardiovascular complications 
  • Metabolic disturbances 
  • Increased malignancy concerns in predisposed individuals 

Use for athletic enhancement or anti-aging lacks strong clinical evidence and carries safety risks. 

FDA-Approved Indications for GH Therapy 

Approved indications include: 

  • Pediatric GH deficiency 
  • Turner syndrome 
  • Prader-Willi syndrome 
  • Chronic renal insufficiency 
  • Adult GH deficiency 

Treatment decisions require endocrinological evaluation and biochemical confirmation. 

When to Refer to a Pediatric Endocrinologist

Referral is appropriate when:

  • A child’s height is below the 3rd percentile 
  • Growth velocity is significantly delayed 
  • Puberty is delayed with growth impairment 
  • IGF-1 levels are abnormal 

A pediatric endocrinologist evaluates candidacy for growth hormone therapy for child patients. 

Side Effects of GH Treatment 

Common side effects include: 

  • Edema 
  • Headache 
  • Injection site reactions 
  • Joint discomfort 

Rare but serious risks require monitoring through: 

  • Regular IGF-1 testing 
  • Glucose monitoring 
  • Growth tracking in children 

Growth Hormone Therapy in Broader Metabolic Context 

It intersects with broader metabolic discussions, including obesity and insulin resistance. For clinicians interested in metabolic therapeutics, see our review on GLP-1 agents in obesity management: GLP1 Therapy

Understanding endocrine pathways is essential for appropriate therapy selection. 

Conclusions

Growth hormone therapy remains a cornerstone treatment for confirmed growth hormone deficiency and specific genetic or endocrine conditions. When prescribed within evidence-based guidelines, it improves growth outcomes in children and metabolic health in adults. 

However, therapy requires specialist oversight, structured monitoring, and careful patient selection. The future of GH therapy lies in precision diagnosis and individualized treatment protocols. 

Frequently Asked Questions

Can growth hormone therapy cause cancer?

Current evidence does not show a significant increase in cancer risk in appropriately treated patients, but individuals with prior malignancy require careful monitoring.

Can growth hormone slow the aging process?

There is no strong clinical evidence supporting GH therapy for anti-aging. Off-label use carries metabolic and cardiovascular risks.

Can growth hormone improve athletic performance?

Use for performance enhancement is not medically approved and may cause serious adverse effects.

What is the best age for growth hormone treatment?

Early diagnosis and treatment during childhood maximize height outcomes. Adult therapy depends on confirmed deficiency.

What is better, TRT or HGH?

Testosterone replacement therapy treats hypogonadism, while this therapy treats GH deficiency. They serve different physiological roles.