HGH (Somatropin) Protocol Guide
Human Growth Hormone (somatropin) is a recombinant 191-amino acid protein identical to endogenous pituitary growth hormone. FDA-approved for adult growth hormone deficiency (AGHD), it stimulates hepatic IGF-1 production, promotes lipolysis, enhances protein synthesis, and supports bone mineralization. In research and clinical settings, HGH is used for body composition optimization, recovery acceleration, anti-aging, and metabolic support. This protocol covers 1-4 IU daily subcutaneous dosing, timing strategies, critical blood work monitoring, and adjunct stacking.
Protocol Overview
- Compound
- Somatropin (rhGH, 191aa)
- Category
- Recombinant Human Growth Hormone
- Mechanism
- Binds GH receptor, stimulates hepatic IGF-1 production, activates JAK2/STAT5 signaling, promotes lipolysis, protein synthesis, chondrogenesis
- MW
- 22,124 Da (191 amino acids)
- Half-Life
- 3-5 hours (subcutaneous)
- Form
- Lyophilized powder or pre-filled pen
- Route
- Subcutaneous
- Frequency
- Daily (5-7 days/week)
- Cycle
- 3-6+ months continuous
Dosing
| Goal | Dose | Frequency | Notes |
|---|---|---|---|
| Anti-Aging / Wellness | 1-2 IU/day | Daily, AM fasted | Low-dose longevity approach; fewer side effects |
| Body Recomposition | 2-4 IU/day | Daily, split AM/pre-bed | Split dosing may improve tolerance |
| Recovery / Healing | 2-3 IU/day | Daily, AM fasted | Enhanced tissue repair and recovery |
| Clinical GHD | 0.2-0.5 mg/day | Daily, before bed | Physician-directed; mimics natural pulse |
1 IU = 0.33 mg somatropin. Administer on empty stomach (insulin/food blunts GH release). Wait 30-60 min before eating. Rotate injection sites (abdomen, thigh, upper arm). Start at 1-2 IU and titrate based on IGF-1 levels.
Timeline
Side Effects & Stacking
Side Effects
- Water retention and joint stiffness (common, dose-dependent)
- Carpal tunnel syndrome (numbness/tingling in hands)
- Insulin resistance / elevated fasting glucose (critical to monitor)
- Hypothyroid conversion (suppressed T4→T3; monitor free T3)
- Edema, especially at higher doses
- Rare: gynecomastia, acromegaly features at supraphysiologic doses
Stacking
- Ipamorelin/CJC-1295: Synergistic GH axis (use on off-days or pulse)
- Semaglutide/Tirzepatide: Counteract insulin resistance, fat loss synergy
- BPC-157 + TB-500: Amplified tissue repair
- Testosterone/TRT: Complementary anabolic signaling
- Metformin: Offset insulin resistance (physician-directed)
Blood Work
| Panel | Markers | Timing |
|---|---|---|
| GH Axis | IGF-1, IGFBP-3 (target IGF-1: 200-300 ng/dL) | Baseline, Week 4, then Q8-12 weeks |
| Glucose | Fasting glucose, HbA1c, fasting insulin, HOMA-IR | Baseline, Week 4, 8, then Q12 weeks |
| Thyroid | TSH, free T3, free T4 | Baseline, Week 8, then Q12 weeks |
| Lipids | Full lipid panel, ApoB | Baseline, Week 12 |
| Basic | CBC, CMP (liver/kidney function) | Baseline, Week 4, then Q12 weeks |
Critical: If fasting glucose exceeds 100 mg/dL or HbA1c exceeds 5.6%, reduce dose or add metformin under physician guidance. Monitor IGF-1 to avoid supraphysiologic levels (>400 ng/dL).
