Somatotropin

Summary

Somatotropin (recombinant human growth hormone, rhGH) is a 191-amino acid polypeptide hormone produced by recombinant DNA technology, identical in structure to endogenous pituitary-derived growth hormone. It is approved for treatment of GH deficiency in children and adults, short stature associated with various conditions, and wasting syndromes.

Mechanism of Action

Binds to growth hormone receptors on target cells, activating the JAK2-STAT5 signaling pathway, stimulating IGF-1 production in the liver and peripheral tissues, promoting anabolic processes including protein synthesis, lipolysis, and longitudinal bone growth.

Routes of Administration

Goals & Uses

• Treatment of growth hormone deficiency (adult)Endocrinology / MetabolismHigh
• Anti-aging / performance enhancementOff Label / IllicitLow
• Short bowel syndromeGastroenterologyModerate
• Short stature associated with Turner syndrome, Prader-Willi syndrome, or SGAPediatric EndocrinologyHigh
• HIV-associated wasting / cachexiaInfectious Disease / MetabolismHigh
• Treatment of growth hormone deficiency (pediatric)Endocrinology / PediatricsHigh

Contraindications

• Active malignancyOncologyHighUse caution or avoid depending on agent and context
• Closed epiphyses (for growth promotion indication)Pediatric / SkeletalModerate
• Acute critical illness (post-surgery, trauma, respiratory failure)Critical CareHigh
• Active proliferative or severe non-proliferative diabetic retinopathyOphthalmologyHigh
• Prader-Willi syndrome with severe obesity or respiratory impairmentGenetic SyndromeHigh
• Hypersensitivity to somatropin or excipientsAllergy / ImmunologyHigh

Adverse Effects

• Fluid retention / peripheral edemaCardiovascularCommon
• Injection site reactionsLocalCommon
• Hyperglycemia / insulin resistanceMetabolic / EndocrineUncommon
• Intracranial hypertension (pseudotumor cerebri)NeurologicalRare
• Slipped capital femoral epiphysisMusculoskeletalRare
• Arthralgia and myalgiaMusculoskeletalCommon

Drug Interactions

• Insulin and oral antidiabetic agentsModerate
• GlucocorticoidsModerate
• Cytochrome P450-metabolized drugs (e.g., cyclosporine, sex steroids, anticonvulsants)Low
• Estrogen (oral)Moderate

Population Constraints

• PregnancyReproductive SafetyRelative
• History of malignancyOncologyRelative
• Diabetes mellitusMetabolicRelative
• NeonatesPediatricRelative
• Hypothyroidism (untreated)EndocrineRelative

Regulatory Status

• European UnionApprovedApproved: Pediatric growth hormone deficiency, Adult growth hormone deficiency, Turner syndrome, Prader-Willi syndrome, Chronic renal insufficiency (pediatric), Small for gestational age with failure to catch upApproved by EMA under multiple brand names; biosimilars authorized via EMA centralized procedure.
• United StatesApprovedApproved: Pediatric growth hormone deficiency, Adult growth hormone deficiency, Turner syndrome, Prader-Willi syndrome, Small for gestational age with failure to catch up, HIV-associated wasting (Serostim), Short bowel syndrome (Zorbtive), Idiopathic short stature (selected formulations)Multiple FDA-approved brand formulations. Classified as Schedule III controlled substance for non-approved use. Biosimilar somatropin products also approved.
• United KingdomApprovedApproved: Pediatric growth hormone deficiency, Adult growth hormone deficiency, Turner syndrome, Prader-Willi syndrome, Small for gestational ageMHRA-approved; NICE guidance restricts some indications. Post-Brexit authorizations align largely with prior EMA approvals.

Multiple FDA-approved brand formulations exist (e.g., Genotropin, Humatrope, Norditropin, Nutropin, Saizen, Serostim, Zorbtive). Classified as a Schedule III controlled substance in the US when used for non-approved purposes. Off-label use for anti-aging and performance enhancement is illegal and not approved.

Evidence & Sources

No sources recorded yet.