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HGH

FDA Approved

Human Growth Hormone | Somatropin

Dose 1-4 IU daily (0.33-1.33mg); start low and titrate up
Frequency Once daily or split into 2 doses (morning and evening)
Cycle 3-6+ months or ongoing for medical GHD
Storage Lyophilized: Room temperature. Reconstituted: 2-8°C, use within 14-28 days

Human Growth Hormone (HGH/Somatropin) is a 191-amino acid polypeptide hormone FDA-approved for pediatric and adult growth hormone deficiency, HIV-associated wasting, and other conditions. It provides both direct and indirect (IGF-1 mediated) anabolic effects.

Mechanism of Action

Binds to GH receptors on target tissues, triggering JAK2-STAT5 signaling pathway. Direct effects include lipolysis, protein synthesis, and metabolic regulation. Indirect effects via IGF-1 promote growth and anabolism. Half-life ~3 hours subcutaneously.

Key Benefits

  • Improved body composition (increased lean mass, decreased fat)
  • Enhanced bone mineral density
  • Improved lipid profile
  • Increased exercise capacity
  • Better quality of life and mood
  • Skin, hair, and nail improvements
  • Enhanced recovery and healing
Molecular Weight
22,124 Da
Chain Length
191 amino acids
Type
Single-chain polypeptide with two disulfide bridges

Growth Hormone Deficiency

  • Pediatric GH Deficiency

    FDA-approved for idiopathic and organic causes, Turner syndrome, Prader-Willi syndrome, SGA, Noonan syndrome, SHOX deficiency.

  • Adult GH Deficiency

    FDA-approved for childhood-onset or adult-onset causes (pituitary tumors, surgery, radiation, trauma).

  • HIV-Associated Wasting

    FDA-approved to increase lean body mass and body weight in cachexia.

Body Composition

  • Fat Loss

    Significant fat loss especially abdominal/visceral fat over 1-3 months.

  • Lean Mass

    Increased muscle mass and improved body composition.

  • Recovery Enhancement

    Enhanced exercise recovery and tissue healing.

Anti-Aging

  • Skin and Hair Quality

    Improved skin elasticity, texture, and hair/nail growth.

  • Energy and Well-being

    Improved energy, sleep, and quality of life.

Subcutaneous injection is the only effective route. Morning fasted injection maximizes fat-burning potential; evening mimics natural nocturnal GH pulse.

GoalDoseFrequencyRoute
Medical GHD (Starting)0.15-0.3mg/day (0.5-1 IU)Once dailySubQ
Medical GHD (Maintenance)0.4-0.8mg/day (1.2-2.4 IU)Once dailySubQ
Anti-Aging/Wellness1-2 IU/day (0.33-0.67mg)Once dailySubQ
Body Recomposition2-4 IU/day (0.67-1.33mg)Once or twice dailySubQ
Performance (Higher Risk)4-8 IU/day (1.33-2.67mg)Split twice dailySubQ

Reconstitution Instructions

Materials Needed:
  • HGH lyophilized powder vial (typically 10 IU or 36 IU)
  • Bacteriostatic water for injection
  • Insulin syringes (29-31 gauge)
  • Alcohol prep pads
  1. 1 Allow vial to reach room temperature (15-20 minutes)
  2. 2 Clean rubber stoppers with alcohol swab
  3. 3 Determine reconstitution volume (typical: 1mL BAC water per 10 IU)
  4. 4 Draw bacteriostatic water slowly, removing air bubbles
  5. 5 Insert needle at angle, aiming stream at vial wall - not directly on powder
  6. 6 Inject water slowly down inside wall, drop by drop
  7. 7 Remove needle and gently swirl in circular motion - never shake
  8. 8 Allow to sit if cloudy, then swirl again until crystal clear
  9. 9 Solution must be crystal clear; discard if cloudy or contains particles
  10. 10 Label with reconstitution date and concentration
  11. 11 Store refrigerated at 2-8°C; use within 14-28 days
Insulin

HGH decreases insulin sensitivity; may require increased insulin doses in diabetics.

monitor
IGF-1/IGF-1 LR3

Synergistic but caution: enhanced effects with increased hypoglycemia and side effect risk.

monitor
Thyroid Hormones (T3/T4)

Increases T4 to T3 conversion; unmasks hypothyroidism in 36-47% of patients.

monitor
CJC-1295

GHRH analog can enhance effects though may be redundant with exogenous HGH.

synergistic
Ipamorelin

Ghrelin mimetic works via different pathway.

synergistic
GHRP-6/GHRP-2

Enhances natural pulsatile release.

synergistic
Cortisol/Hydrocortisone

Can unmask cortisol deficiency; replacement should precede HGH.

monitor
Testosterone

Commonly combined in hormone replacement therapy.

synergistic
Metformin

May manage insulin resistance; may reduce IGF-1 levels.

monitor
Semaglutide/Tirzepatide

GLP-1 agonists help manage insulin resistance during HGH therapy.

compatible
Week 1-2

Improved sleep quality, increased energy, possible water retention and joint stiffness

Week 2-4

Enhanced exercise recovery, skin improvement, possible carpal tunnel symptoms

Month 1-2

Noticeable fat loss (especially abdominal), improved skin elasticity and texture

Month 2-3

Continued fat loss, lean mass improvements, hair/nail growth, reduced recovery time

Month 3-6

Significant body composition changes, improved bone density, sustained energy/well-being

Long-term

Maintained benefits; effects diminish weeks-months after discontinuation

Common Side Effects

  • Water retention and fluid accumulation
  • Joint pain and stiffness
  • Carpal tunnel syndrome (usually resolves with dose reduction)
  • Headaches
  • Numbness/tingling in hands

Stop Signs - Discontinue if:

  • Severe or worsening carpal tunnel symptoms
  • Signs of diabetes (increased thirst, frequent urination, blurred vision)
  • Severe edema (facial, hand, or feet swelling)
  • Severe joint/muscle pain unresponsive to dose reduction
  • New lumps, masses, or rapidly growing moles
  • Severe headaches or vision changes
  • Signs of allergic reaction
  • Gynecomastia (breast tissue growth in males)
  • Hypothyroid symptoms (fatigue, weight gain, cold intolerance)

Contraindications

  • Active cancer (may accelerate tumor growth)
  • Acute critical illness (increased mortality in ICU patients)
  • Closed epiphyses in children (for growth promotion)
  • Pregnancy/breastfeeding

Good Signs

  • White to off-white lyophilized powder or solid cake (not liquid/collapsed)
  • Crystal clear reconstituted solution with no particles
  • Intact vacuum in sealed vial (resistance when inserting needle)
  • Pharmaceutical grade with certificate of analysis (Genotropin, Norditropin, Humatrope preferred)

Warning Signs

  • Generic/underground lab products have highly variable quality and potency
  • Common counterfeits exist; third-party testing recommended

Bad Signs

  • Cloudy, discolored, or particles visible indicates degradation
  • Powder appears melted or stuck to vial (improper storage)
  • Yellow/brown coloring
  • KIMS Long-Term Safety Study
    (2020)

    15,809 patients, mean 5.3 years follow-up. Largest long-term safety study showing de novo cancer incidence comparable to general population (SIR 0.92).

  • Long-term Efficacy and Safety in Adult GHD
    (2018)

    Systematic review demonstrating improvements in body composition, muscle strength, quality of life, bone mass/density, and lipoprotein patterns.

  • Effects on Morbidity - Systematic Review
    (2016)

    Demonstrated positive effects on cardiovascular surrogate markers and bone metabolism.

  • GH-Thyroid Hormone Interaction Study
    (2015)

    GH replacement unmasks central hypothyroidism in 36-47% of apparently euthyroid patients.

Disclaimer

This information is for educational and research purposes only. Consult a healthcare professional before use.