Recombinant Human Growth Hormone (rhGH)
Recombinant Human Growth Hormone (rhGH)
Recombinant human growth hormone (rhGH) is a synthetic version of the endogenous growth hormone produced by the anterior pituitary gland. It plays a crucial role in promoting linear growth, metabolism, and body composition.
Key Points
- Molecular Weight: 22 kDa
- Half-life: 2-3 hours
- Route: Subcutaneous injection
- Frequency: Daily administration
Mechanism of Action
- Direct effects:
- Stimulates hepatic IGF-1 production
- Promotes chondrocyte proliferation
- Enhances amino acid uptake
- Increases protein synthesis
- Indirect effects through IGF-1:
- Stimulates longitudinal bone growth
- Promotes cell differentiation
- Enhances muscle growth
- Improves bone mineralization
- Metabolic effects:
- Increases lipolysis
- Promotes protein anabolism
- Enhances glucose metabolism
Clinical Indications
FDA-Approved Indications:
- Growth Hormone Deficiency (GHD)
- Congenital
- Acquired
- Idiopathic
- Turner Syndrome
- Prader-Willi Syndrome
- Small for Gestational Age (SGA) without catch-up growth
- SHOX deficiency
- Chronic Renal Insufficiency
- Idiopathic Short Stature (ISS)
- Noonan Syndrome
Dosing & Administration
Standard Dosing by Indication:
- GH Deficiency: 0.024-0.034 mg/kg/day
- Turner Syndrome: 0.05 mg/kg/day
- Prader-Willi Syndrome: 0.035 mg/kg/day
- SGA: 0.035-0.067 mg/kg/day
- Chronic Renal Insufficiency: 0.05 mg/kg/day
- SHOX deficiency: 0.05 mg/kg/day
- ISS: 0.034-0.067 mg/kg/day
Administration Guidelines:
- Subcutaneous injection
- Rotate injection sites
- Evening administration preferred
- Store refrigerated (2-8°C)
Monitoring & Safety
Regular Monitoring:
- Growth velocity
- Height and weight
- IGF-1 levels
- Bone age (annually)
- Thyroid function
- Glucose metabolism
- Spine examination for scoliosis
Common Side Effects:
- Injection site reactions
- Headache
- Hip pain
- Arthralgia
- Peripheral edema
- Insulin resistance
Serious Adverse Events:
- Intracranial hypertension
- Slipped capital femoral epiphysis
- Scoliosis progression
- Pancreatitis
Contraindications & Precautions
Absolute Contraindications:
- Active malignancy
- Active proliferative or severe non-proliferative diabetic retinopathy
- Acute critical illness
- Closed epiphyses
Relative Contraindications:
- Severe scoliosis
- Severe obesity
- Uncontrolled diabetes
- Sleep apnea
Special Populations:
- PWS patients with severe obesity
- History of malignancy
- Concurrent glucocorticoid therapy
