HGH Half-Life: How Long It Stays in Your System
How long HGH stays in the body, how that shapes dosing frequency, and what is known about drug testing.
- Half-life
- 0.4 hours IV; 3.0 hours subcutaneous
- intravenous (normal adults); subcutaneous (GHD adults), Genotropin, in people · FDA label (Genotropin)
- Dosing interval
- Varies by study
- as used in studies
- WADA
- Prohibited (S2.2.3)
- In and out of competition
- Detection window
- Not found
- None reported as of 2 Oct 2026
HGH half-life
A half-life depends on the route (under the skin, into a vein, by mouth or nasal spray) and the species it was measured in, so we report each value with its route and source.
| Route | Half-life | Measured in | Source |
|---|---|---|---|
| intravenous (normal adults); subcutaneous (GHD adults), Genotropin | 0.4 hours IV; 3.0 hours subcutaneous | People | FDA label (Genotropin) |
| subcutaneous (GHD patients), Norditropin | approximately 7 to 10 hours | People | FDA label (Norditropin) |
| subcutaneous (healthy subjects), Humatrope | 3.8 (1.4) hours | People | FDA label (Humatrope) |
| As labelled | 0.4 hours IV in normal adults; 3.0 hours subcutaneous in GHD adults | People | FDA label (Genotropin) |
| As labelled | About 21.1 minutes after intravenous infusion | People | FDA label (Norditropin) |
| As labelled | Approximately 7 to 10 hours after subcutaneous dosing in GHD patients | People | FDA label (Norditropin) |
| As labelled | 3.8 (1.4) hours after subcutaneous dosing | People | FDA label (Humatrope) |
What half-life means
Half-life is the time it takes for the amount of a drug in the blood to fall by half. After one half-life, about 50% is left; after two, about 25%; after four to five, only a few percent remain.
- A long half-life lets a drug be dosed less often, for example once a week.
- A short half-life means levels rise and fall quickly, which is why some peptides are given daily or more often.
- Effects can outlast blood levels, so half-life alone does not tell you how long a drug works.
What it means for dosing frequency
Dosing intervals used in published studies of HGH:
- daily, not stated (Human RCT; Journal of applied physiology 2014, PMID 24235105)
- not stated, not stated (Human RCT; European journal of endocrinology 2013, PMID 23447518)
- two injections, local injection into the patellar tendon (Human RCT; Journal of applied physiology 2012, PMID 22961272)
- daily, subcutaneous (rhGH, per design) (Human RCT; The Journal of clinical endocrinology and metabolism 2006, PMID 16332938)
Changing the interval changes how much drug builds up between doses, so it is not a free choice.
Drug tests and sport
Prohibited by WADA (S2.2.3)Growth hormone and its analogues and fragments are prohibited at all times (S2.2.3).
Anti-doping labs use tests built for specific substances. Whether a given test detects HGH, and for how long, is not reported in the anti-doping literature we checked (as of 2 Oct 2026). Tested athletes should treat it as prohibited (s2.2.3) at all times.
Common questions
How long does HGH stay in your system?
Its reported half-life is 0.4 hours IV; 3.0 hours subcutaneous (intravenous (normal adults); subcutaneous (GHD adults), Genotropin); approximately 7 to 10 hours (subcutaneous (GHD patients), Norditropin). Most of a dose is gone after about four to five half-lives.
What is the half-life of HGH?
0.4 hours IV; 3.0 hours subcutaneous (intravenous (normal adults); subcutaneous (GHD adults), Genotropin); approximately 7 to 10 hours (subcutaneous (GHD patients), Norditropin), from the sources cited below.
Is HGH on the WADA prohibited list?
Yes. Prohibited by WADA (S2.2.3).
More on HGH
Sources
- 1World Anti-Doping Code International Standard Prohibited List 2026World Anti-Doping Agency · 2026wada-ama.orgAccessed 2 Oct 2026
- 2GENOTROPIN (SOMATROPIN) KIT [PFIZER LABORATORIES DIV PFIZER INC]FDA label (Genotropin), DailyMed · current labeldailymed.nlm.nih.govAccessed 2 Oct 2026
- 3NORDITROPIN (SOMATROPIN) INJECTION, SOLUTION [NOVO NORDISK]FDA label (Norditropin), DailyMed · current labeldailymed.nlm.nih.govAccessed 2 Oct 2026
- 4HUMATROPE (SOMATROPIN) KIT [ELI LILLY AND COMPANY]FDA label (Humatrope), DailyMed · current labeldailymed.nlm.nih.govAccessed 2 Oct 2026
- 5Effect of growth hormone on aging connective tissue in muscle and tendon: gene expression, morphology, and function following immobilization and rehabilitation.Journal of applied physiology (Bethesda, Md. : 1985) · 2014PMID 24235105Accessed 2 Oct 2026
- 6Impact of GH replacement therapy on sleep in adult patients with GH deficiency of pituitary origin.European journal of endocrinology · 2013PMID 23447518Accessed 2 Oct 2026
- 7Local administration of growth hormone stimulates tendon collagen synthesis in elderly men.Journal of applied physiology (Bethesda, Md. : 1985) · 2012PMID 22961272Accessed 2 Oct 2026
- 8The effects of growth hormone and/or testosterone in healthy elderly men: a randomized controlled trial.The Journal of clinical endocrinology and metabolism · 2006PMID 16332938Accessed 2 Oct 2026
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