Somatropin
Also known as: Recombinant human GH, rhGH, Genotropin, Norditropin, Humatrope, Omnitrope
Recombinant human growth hormone, FDA-approved since 1987 for growth disorders and adult GH deficiency. Prescription only; non-medical use is illegal.
Last updated
Mechanism of Action
Somatropin has the same 191-amino-acid sequence as pituitary growth hormone. It binds the growth hormone receptor, activating JAK2-STAT5 signaling, which drives hepatic and local production of IGF-1. GH and IGF-1 together stimulate linear bone growth at open growth plates, protein synthesis and lipolysis, and GH has anti-insulin effects that raise blood glucose. Unlike secretagogues such as sermorelin or tesamorelin, it replaces the hormone directly rather than prompting the pituitary to release it.
- Half-life
- ~20-30 minutes IV; ~2-4 hours after subcutaneous injection
- Administration Routes
- Subcutaneous
- Research Status
- Clinical
Reported Benefits
- Increases growth in children with GH deficiency, Turner syndrome, Prader-Willi syndrome, SGA, CKD and other labeled conditions
- Replacement therapy for diagnosed adult GH deficiency (body composition, bone density, lipids)
- Labeled for HIV-associated wasting (Serostim)
Potential Side Effects
- Fluid retention, edema, joint and muscle pain, carpal tunnel symptoms
- Reduced insulin sensitivity and higher blood glucose
- Intracranial hypertension and slipped capital femoral epiphysis in children
- Possible increased risk of new or recurrent tumors in cancer survivors
- Fatalities reported in Prader-Willi patients with severe obesity or respiratory impairment
Common Dosing
Labeled pediatric dosing is weight-based (mg/kg per week), usually divided into daily subcutaneous injections and adjusted by growth response and IGF-1. Adults with GH deficiency typically start at a low daily dose that is titrated to keep IGF-1 in the age-appropriate range and minimize side effects. Diagnosis requires stimulation testing, and dosing is set and supervised by the prescribing clinician.
The dosing information above is aggregated from research literature and anecdotal community reports for educational purposes only. It is not a recommendation, prescription, or medical advice. Peptides are sold as research chemicals only and are not intended for human use.
Contraindications
- Active malignancy
- Acute critical illness after open-heart or abdominal surgery, multiple trauma, or acute respiratory failure
- Prader-Willi syndrome with severe obesity or severe respiratory impairment
- Active proliferative or severe nonproliferative diabetic retinopathy; growth promotion after epiphyses close
No documented stacking partners for Somatropin yet.
- View
Evaluation and treatment of adult growth hormone deficiency: an Endocrine Society clinical practice guideline
2011
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Guidelines for Growth Hormone and Insulin-Like Growth Factor-I Treatment in Children and Adolescents: Growth Hormone Deficiency, Idiopathic Short Stature, and Primary Insulin-Like Growth Factor-I Deficiency
2016
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Systematic review: the safety and efficacy of growth hormone in the healthy elderly
2007
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Systematic review: the effects of growth hormone on athletic performance
2008