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Protein hormoneHuman trialsFDA approved

HGH

Human growth hormone

Last reviewed October 27, 2026 · 21 sources · Written for general readers · Compare with another compound →

The bottom line

Somatropin is a well studied, FDA approved prescription drug for specific growth hormone problems in children and adults. In healthy people it trims fat and adds lean mass, partly water, but trials show little or no gain in strength or endurance, and side effects such as swelling, joint pain and higher blood sugar are common. Distributing it for anti aging or bodybuilding is a federal crime, and products sold outside pharmacies are often fake.

Where the evidence stands

What it is

Human growth hormone (HGH) is a protein made by the pituitary gland. The drug version, somatropin, is made in bacteria using DNA technology. It has 191 amino acids, the same sequence as the natural hormone, and weighs about 22,000 daltons.[1] Because it is a large protein, no simple chemical formula is listed here.

FDA approved somatropin brands on DailyMed include Genotropin, Humatrope, Norditropin, Omnitrope, Serostim and Zomacton.[2] The Genotropin label lists these approved uses: growth failure in children from growth hormone deficiency, Prader-Willi syndrome, being born small for gestational age without catch up growth by age 2, Turner syndrome and idiopathic short stature (short stature with no known cause), plus hormone replacement in adults with growth hormone deficiency.[1]

FDA has also approved long acting forms given once a week. One is lonapegsomatropin (Skytrofa), which is somatropin attached to a carrier that slowly releases it after the shot. Its label covers children 1 year and older with growth failure from too little growth hormone, and adults with growth hormone deficiency.[3]

Federal law makes it a crime to knowingly distribute HGH, or hold it in order to distribute it, for any human use other than treating a disease or recognized medical condition authorized by FDA, under a doctor's order. The law covers somatropin and its analogues.[4]

Name
HGH (Human growth hormone)
Other names
somatropin, hGH, GH, recombinant human growth hormone
Type
Protein hormone

What it does in the body

Growth hormone is a natural protein of 191 amino acids made by the pituitary gland at the base of the brain.[1][5] It acts on many tissues, and much of its work is done by IGF-1, a growth factor the body makes in response.[5] The drug somatropin has the same sequence as the natural hormone.[1]

This is the biology, area by area. A change measured in the body, like a higher blood level, does not always mean a person feels a benefit. The claims check below covers that.

Bones and growth

Well established

In children who lack growth hormone, somatropin makes bones grow longer while the growth plates at the ends of bones are still open, which is why it is used for several childhood growth disorders.[1] Once growth plates close in adulthood, it can no longer add height.[1]

Fat and body makeup

Measured in people

Growth hormone breaks down stored fat.[5] In 37 placebo controlled trials in adults with growth hormone deficiency, treatment lowered fat mass by about 3.1 kg and raised lean mass by about 2.7 kg.[8] In healthy older adults treated for about 27 weeks on average, fat fell about 2.1 kg while body weight did not change.[9]

Muscle and strength

Measured in people

Growth hormone raises lean body mass, but much of that gain is extra body water rather than muscle.[7][6] Across 27 randomized study groups of healthy people, lean mass rose about 2.1 kg while strength and exercise capacity did not improve.[10]

Blood sugar

Measured in people

Growth hormone works against insulin, so cells take up sugar less readily, and the label warns of glucose intolerance and diabetes.[1] In placebo controlled trials in deficient adults, fasting blood sugar and insulin rose slightly, a sign of reduced insulin sensitivity.[8] In one trial of older adults, 18 men on growth hormone developed diabetes or glucose intolerance versus 7 men not on it.[11]

Heart and blood vessels

Measured in people

In adults with growth hormone deficiency, a pooled analysis of 37 placebo controlled trials found that treatment lowered total and LDL cholesterol and slightly lowered the bottom number of blood pressure.[8] The authors noted that no large trial has shown fewer heart attacks or strokes.[8] In healthy older adults, most blood fats did not improve.[9]

Fluid, nerves and joints

Measured in people

Growth hormone makes the body hold on to water, which is part of why lean mass rises.[6] In older adults on growth hormone, swelling affected about 39 percent of women and joint pain about 41 percent of men, and carpal tunnel symptoms, from swelling that presses on a wrist nerve, were common.[11]

Aging and lifespan

Seen in animals

In mice, genetic changes that lower growth hormone and IGF-1 activity are linked to longer life and protection from cancer and diabetes, the opposite of anti aging marketing.[12] Whether this applies to people is not known.[12]

How it works

Growth hormone acts on many tissues. It raises IGF-1, a growth factor that carries out many of its effects, and changes how the body handles fat, sugar and protein.[1][5]

  • In children who lack it, it helps bones grow while the growth plates are still open. That is why it is not used to promote growth once the growth plates have closed.[1]
  • It has anabolic (tissue building) and lipolytic (fat breaking) effects.[5]
  • It makes the body hold on to water, so part of the lean mass gain seen in studies is extra fluid rather than muscle.[6][7]
  • It can make the body less sensitive to insulin, which can raise blood sugar.[1]
  • Too much growth hormone for a long time can cause a condition like acromegaly, a disease of excess growth hormone that raises the risk of illness and death.[6]

These effects are well established from decades of medical use and many controlled trials.

What the research shows

We keep animal and human evidence apart. A result in animals is a reason to study something in people, not proof that it works in people.

Animal and lab studies

Mouse lifespan studies point the other way

  • Somatropin is an approved drug, and its uses, warnings and side effects are defined mainly by human data in its FDA label.[1]
  • In mice, several genetic changes that lower growth hormone and IGF-1 activity are linked to longer life and protection from cancer and diabetes, the opposite of what anti aging marketing implies.[12]
  • A review of this work notes that whether lower growth hormone activity lengthens human life has not been shown, and that the evidence for growth hormone as an anti aging treatment is lacking.[12]
  • Reviews of its abuse in sport rely on human pharmacology and doping cases rather than animal work.[5]

Limit: These mouse results came from genetic changes, not from taking or avoiding a drug, and may not apply to people.

Human studies

Strong for approved uses, weak for performance and aging

  • Its approved uses in children and adults with specific growth disorders are set out in its FDA label.[1]
  • A pooled analysis of 37 blinded, placebo controlled trials in adults with growth hormone deficiency found treatment cut fat mass about 3.1 kg, raised lean mass about 2.7 kg, lowered total and LDL cholesterol and slightly lowered diastolic blood pressure, while fasting blood sugar and insulin rose slightly.[8]
  • In 1990, 21 healthy men aged 61 to 81 with low IGF-1 were followed for a year. The 12 who received shots under the skin for 6 months gained 8.8 percent lean mass, lost 14.4 percent fat and gained 1.6 percent spine bone density, while the 9 untreated men did not change. Side effects were not reported in the summary.[13]
  • In a 26 week double blind trial of 131 adults aged 65 to 88, growth hormone with or without sex hormones raised lean mass and cut fat. Women's strength did not change significantly, and men gained strength only with growth hormone plus testosterone, by a borderline amount.[11]
  • In that trial, swelling hit about 39 percent of women on growth hormone versus none on placebo, joint pain about 41 percent of men on growth hormone, and carpal tunnel symptoms 32 percent of men on growth hormone plus testosterone. Diabetes or glucose intolerance appeared in 18 men on growth hormone versus 7 men not on it.[11]
  • A systematic review of 18 trial groups in healthy older adults, with 220 people treated for about 27 weeks on average, found fat fell 2.1 kg and lean mass rose 2.1 kg, with no change in weight, bone density or most blood fats. Swelling, joint pain, carpal tunnel syndrome and breast growth in men were more common.[9]
  • A systematic review of 27 randomized study groups, with 303 people given growth hormone, found lean body mass rose by about 2.1 kg compared with controls, but strength and exercise capacity did not improve. Swelling and fatigue were more common.[10]
  • In a placebo controlled trial of 96 recreational athletes, 8 weeks of shots cut fat and raised lean mass through extra water. Sprint capacity rose about 3.9 percent, while strength, endurance and jump height did not change.[7]
  • A later review found the lean mass gain may be partly water. Growth hormone did not clearly improve strength, power or endurance, though it may help short bursts of anaerobic effort.[6]
  • In 40 children with severe burns, a double blind placebo controlled trial found growth hormone shortened healing of skin graft donor sites and cut hospital stay from about 46 to 32 days for a typical burn size.[14]
  • In two placebo controlled trials in more than 500 intensive care patients, high doses of growth hormone roughly doubled the death rate in the hospital, 39 percent versus 20 percent in one trial and 44 percent versus 18 percent in the other.[16]
  • A French registry of 6,928 people treated with growth hormone as children between 1985 and 1996 found death rates about a third higher than in the general population, about three times higher in those given the highest doses, with more deaths from bone tumors and bleeding in the brain but not from cancer overall. This was an observational study, so it cannot prove the drug was the cause.[17]

Limit: Trials in healthy people were small and short, and people who misuse growth hormone often take far more than was tested, so harms may be larger.

Claims check

The most common claims about this compound, and what studies actually found. Verdicts rate the evidence, not whether you should use it.

Builds muscle

Mixed results

A review of 27 randomized study groups in healthy people found lean body mass rose about 2.1 kg more than in controls, but strength did not improve.[10] In a 26 week placebo controlled trial of 131 adults aged 65 to 88, men on growth hormone gained 3.1 kg of lean mass, yet their strength did not change significantly.[11] In 96 recreational athletes, the lean mass gain came from extra body water.[7]

Burns fat

Shown in people

In a review of 18 randomized study groups in healthy older adults, with 220 people treated for about 27 weeks on average, fat mass fell about 2.1 kg.[9] Fat mass also fell in the 131 person JAMA trial and in the 96 athletes over 8 weeks.[11][7] Body weight did not change, because lean mass and water rose at the same time.[9]

Boosts athletic performance

Mixed results

A systematic review found no improvement in strength or exercise capacity, and more swelling and fatigue.[10] In a placebo controlled trial of 96 recreational athletes over 8 weeks, sprint capacity rose about 3.9 percent, but strength, endurance and jump height did not change, and the sprint gain was gone 6 weeks after stopping.[7]

Reverses aging

Mixed results

In 1990, 12 men over 60 given growth hormone for 6 months gained 8.8 percent lean mass and lost 14.4 percent fat compared with 9 untreated men.[13] Later controlled trials found the changes were small, bone density and most blood fats did not improve, and side effects were common. The review authors concluded growth hormone cannot be recommended as an anti aging therapy.[9] In mice, lower growth hormone activity is linked to longer life, not shorter.[12]

Improves cholesterol and heart health

Mixed results

In adults who truly lack growth hormone, a pooled analysis of 37 placebo controlled trials found lower total and LDL cholesterol and slightly lower diastolic blood pressure, but also slightly higher blood sugar and insulin.[8] In healthy older adults, most blood fats did not improve.[9] No trial has shown fewer heart attacks or deaths.

Speeds recovery from illness or injury

Mixed results

In double blind trials of children with severe burns, growth hormone shots shortened healing of skin graft donor sites, from about 8.5 to under 7 days in one trial, and shortened hospital stays.[14][15] But in two placebo controlled trials of more than 500 adults in intensive care, high doses of growth hormone roughly doubled the death rate in the hospital, 39 versus 20 percent in one trial and 44 versus 18 percent in the other.[16] The label says it should not be used in acute critical illness.[1] Benefit depends heavily on who is treated.

Treats growth hormone deficiency and certain growth disorders

Shown in people

FDA approved somatropin for growth failure in children with growth hormone deficiency and several genetic and growth conditions, and for adults with growth hormone deficiency, based on human data summarized in the label.[1]

Known risks and side effects

  • Blood sugar and diabetes. The label warns that somatropin can cause glucose intolerance and diabetes.[1] In one trial of older adults, 18 men on growth hormone developed diabetes or glucose intolerance versus 7 men not on it.[11]
  • Swelling, joint pain and carpal tunnel. In older adults, swelling affected about 39 percent of women and joint pain about 41 percent of men on growth hormone, versus none on placebo.[11] Reviews also find more carpal tunnel syndrome, fatigue and breast growth in men.[9][10]
  • Other label warnings, including tumors. Label warnings include raised pressure inside the skull, pancreatitis, a hip growth plate problem in children called slipped capital femoral epiphysis, and a risk of new tumors or tumor growth. It should not be used in people with active cancer.[1] In a French follow up of 6,928 people treated as children, deaths from bone tumors and brain bleeds were higher than expected, though the study could not prove cause.[17]
  • Danger in critical illness. It should not be used in people with acute critical illness, after trials showed higher death rates in intensive care patients.[1][16]
  • Fake products and legal risk. Falsified biotech drugs, including growth hormone, can contain the wrong ingredient, the wrong amount, nothing active, or toxic contaminants.[18] In one study of 1,190 doping products seized at the Swiss border, fewer than 20 percent held the claimed amount.[19] Distributing HGH for unapproved uses can bring up to 5 years in prison, or up to 10 years if a person under 18 is involved.[4]

Regulatory status

Today: Somatropin and its once weekly long acting forms are FDA approved, by prescription, for specific medical conditions.[1][3] Distributing growth hormone for other uses, such as anti aging or bodybuilding, is a federal crime under 21 U.S.C. 333(e).[4] WADA bans growth hormone, its analogues such as somapacitan and its fragments at all times, in the 2026 list and in the 2027 list that takes effect January 1, 2027.[20][21]

  1. Congress added the HGH distribution crime to federal law in Pub. L. 101-647.[4]
  2. Congress amended the wording of the HGH provision in Pub. L. 103-322.[4]
  3. The Skytrofa (lonapegsomatropin) label was revised and covers both children with growth failure and adults with growth hormone deficiency.[3]
  4. The 2026 WADA Prohibited List took effect and bans growth hormone and its analogues.[20]
  5. The Genotropin label was most recently revised, with its approved uses and warnings as summarized here.[1]
  6. WADA published its 2027 Prohibited List, which again bans growth hormone, its analogues and fragments.[21]
  7. The 2027 WADA Prohibited List takes effect.[21]

Sources

  1. Pfizer. GENOTROPIN (somatropin) for injection. Prescribing information, revised July 2026. DailyMed. DailyMed
  2. National Library of Medicine. DailyMed search results for somatropin. DailyMed
  3. Ascendis Pharma. SKYTROFA (lonapegsomatropin-tcgd) for injection. Prescribing information, highlights revised September 2025. DailyMed. DailyMed
  4. 21 U.S.C. 333(e). Prohibited distribution of human growth hormone. Legal Information Institute, Cornell Law School. 21 U.S.C. 333
  5. Holt RIG, Sonksen PH. Growth hormone, IGF-I and insulin and their abuse in sport. Br J Pharmacol. 2008;154(3):542-556. PMID 18376417
  6. Birzniece V, Nelson AE, Ho KKY. Growth hormone and physical performance. Trends Endocrinol Metab. 2011;22(5):171-178. PMID 21420315
  7. Meinhardt U, Nelson AE, Hansen JL, Birzniece V, Clifford D, Leung KC, et al. The effects of growth hormone on body composition and physical performance in recreational athletes: a randomized trial. Ann Intern Med. 2010;152(9):568-577. PMID 20439575
  8. Maison P, Griffin S, Nicoue-Beglah M, Haddad N, Balkau B, Chanson P. Impact of growth hormone (GH) treatment on cardiovascular risk factors in GH-deficient adults: a metaanalysis of blinded, randomized, placebo-controlled trials. J Clin Endocrinol Metab. 2004;89(5):2192-2199. PMID 15126541
  9. Liu H, Bravata DM, Olkin I, Nayak S, Roberts B, Garber AM, Hoffman AR. Systematic review: the safety and efficacy of growth hormone in the healthy elderly. Ann Intern Med. 2007;146(2):104-115. PMID 17227934
  10. Liu H, Bravata DM, Olkin I, et al. Systematic review: the effects of growth hormone on athletic performance. Ann Intern Med. 2008;148(10):747-758. PMID 18347346
  11. Blackman MR, Sorkin JD, Münzer T, Bellantoni MF, Busby-Whitehead J, Stevens TE, et al. Growth hormone and sex steroid administration in healthy aged women and men: a randomized controlled trial. JAMA. 2002;288(18):2282-2292. PMID 12425705
  12. Junnila RK, List EO, Berryman DE, Murrey JW, Kopchick JJ. The GH/IGF-1 axis in ageing and longevity. Nat Rev Endocrinol. 2013;9(6):366-376. PMID 23591370
  13. Rudman D, Feller AG, Nagraj HS, Gergans GA, Lalitha PY, Goldberg AF, et al. Effects of human growth hormone in men over 60 years old. N Engl J Med. 1990;323(1):1-6. PMID 2355952
  14. Herndon DN, Barrow RE, Kunkel KR, Broemeling L, Rutan RL. Effects of recombinant human growth hormone on donor-site healing in severely burned children. Ann Surg. 1990;212(4):424-429. PMID 2121109
  15. Gilpin DA, Barrow RE, Rutan RL, Broemeling L, Herndon DN. Recombinant human growth hormone accelerates wound healing in children with large cutaneous burns. Ann Surg. 1994;220(1):19-24. PMID 8024354
  16. Takala J, Ruokonen E, Webster NR, et al. Increased mortality associated with growth hormone treatment in critically ill adults. N Engl J Med. 1999;341(11):785-792. PMID 10477776
  17. Carel JC, Ecosse E, Landier F, Meguellati-Hakkas D, Kaguelidou F, Rey G, Coste J. Long-term mortality after recombinant growth hormone treatment for isolated growth hormone deficiency or childhood short stature: preliminary report of the French SAGhE study. J Clin Endocrinol Metab. 2012;97(2):416-425. PMID 22238382
  18. Janvier S, De Spiegeleer B, Vanhee C, et al. Falsification of biotechnology drugs: current dangers and/or future disasters? J Pharm Biomed Anal. 2018;161:175-191. PMID 30165334
  19. Weber C, Krug O, Kamber M, et al. Qualitative and Semiquantitative Analysis of Doping Products Seized at the Swiss Border. Subst Use Misuse. 2017;52(6):742-753. PMID 28156209
  20. World Anti-Doping Agency. World Anti-Doping Code: 2026 Prohibited List, section S2.2.3 (growth hormone, its analogues and fragments). In force January 1, 2026. WADA
  21. World Anti-Doping Agency. World Anti-Doping Code International Standard: Prohibited List 2027, sections S2 and S4.3. Published September 2026; in force January 1, 2027. WADA 2027
Medical disclaimer

This page is educational information only. It is not medical advice and does not replace care from a licensed medical provider. Do not use this page to decide whether to take any substance. Talk to a licensed medical provider first.

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