At a Glance
Quickcomparison
Dose Range
IGF-1 LR3
20–100 mcg
Human Growth Hormone (HGH)
1–4 IU
Frequency
Once daily
Administration
Subcutaneous injection
Cycle Length
4-6 weeks
12+ weeks
Onset Speed
Rapid (hours to days)
Gradual (3-4 weeks)
Evidence Level
Strong preclinical (extensive animal studies)
Strong human trials (Phase 3 or FDA approved)
Efficacy
Benefitratings
Muscle Growth
Recovery Speed
Nutrient Utilization
Body Composition
Recovery & Healing
Anti-Aging Effects
Technical Data
Compoundspecifications
Molecular Formula
C400H625N111O115S9
Molecular Weight
9111.4 g/mol
Half-Life
20-30 hours
Bioavailability
High when injected subcutaneously or intramuscularly
CAS Number
946870-92-4
C990H1529N263O299S7
22,124 Da (22.124 kDa)
2-4 hours (endogenous), varies by formulation for synthetic
70-90% (subcutaneous injection)
12629-01-5
Protocols
Dosingtiers
starting
0.15-0.30 mg/day (approx. 0.2 mg/day)
First 1-2 months before titration
FDA-labeled non-weight-based starting dose for adult growth hormone deficiency (Genotropin) [6]. Lower starting doses and smaller increments are advised for older patients.
standard
Titrate by 0.1-0.2 mg/day to target (commonly 0.2-0.6 mg/day)
Adjusted every 1-2 months
Dose titrated every 1-2 months to clinical response and serum IGF-1 per FDA label [6].
advanced
Not more than 0.04 mg/kg/week initially, up to 0.08 mg/kg/week
Divided into 6-7 daily injections
Titrated at 4-8 week intervals
FDA-labeled weight-based regimen ceiling for adult GH deficiency (Genotropin) [6].
Applications
Bestsuited for
Serious Muscle Builders
If you're pushing hard in the gym and want to maximize every rep, IGF-1 LR3 helps your muscles grow through both hypertrophy (bigger cells) AND hyperplasia (more cells). That's a one-two punch that few other compounds offer.
Recovery-Focused Athletes
Train hard, recover faster. IGF-1 LR3 accelerates tissue repair and reduces the time you need between intense sessions. It's particularly valuable during high-volume training blocks or when preparing for competition.
Body Recomposition Goals
Looking to build muscle while losing fat? IGF-1 LR3 helps shuttle nutrients into muscle cells while improving how your body uses fat for fuel. Combined with proper diet, it supports that lean, muscular physique.
Post-Injury Rehabilitation
IGF-1 is your body's natural repair signal. The LR3 version stays active longer, potentially helping injured tissues heal more completely. Athletes recovering from muscle strains or tears may find it particularly beneficial.
Anti-Aging and Longevity Seekers
HGH naturally declines as you age—by 60, you may have only 20% of what you had at 20. Replacement therapy can help restore youthful energy, improve skin quality, maintain muscle mass, and support overall vitality. Think of it as giving your body back the building blocks it's been missing.
HGH is one of the few compounds that helps you build lean muscle while simultaneously burning fat. It enhances protein synthesis for muscle growth while mobilizing fat stores for energy. The result? A leaner, more muscular physique—especially when combined with proper training and nutrition.
Recovery and Healing
Whether you're recovering from surgery, a sports injury, or just intense training, HGH accelerates tissue repair. It promotes collagen synthesis, speeds wound healing, and helps tendons and ligaments recover faster. Athletes and fitness enthusiasts particularly value this benefit.
Sleep Quality Improvement
Many HGH users report significantly better sleep—falling asleep faster, sleeping deeper, and waking up feeling more refreshed. This makes sense because growth hormone is naturally released in pulses during deep sleep. Better sleep means better recovery, mood, and cognitive function.
Safety Profile
Sideeffects
Common
Hypoglycemia (low blood sugar)
Injection site reactions
Water retention
Headaches
Uncommon
Joint pain or stiffness
Numbness or tingling
Serious
Severe hypoglycemia
Water retention and swelling
Joint and muscle pain
Carpal tunnel symptoms
Elevated blood sugar
Gynecomastia (in men)
Intracranial hypertension
Research Status
Safety& evidence
FDA Status
Research compound
Safety Overview
IGF-1 LR3 has been extensively studied in research settings and shows a predictable side effect profile when used responsibly. The primary concern is hypoglycemia, which is manageable with proper nutrition timing. Long-term safety data in humans is limited since it's used as a research compound. Joint discomfort and water retention are generally mild and resolve when cycling off.
Contraindications
xActive cancer or history of cancer
xPregnancy or breastfeeding
xDiabetic retinopathy or uncontrolled diabetes
xKnown hypersensitivity to IGF-1 or related peptides
xChildren and adolescents (can affect growth plates)
FDA approved for other use
Recombinant human growth hormone has been FDA-approved since 1985 and has extensive safety data from decades of clinical use. When used at appropriate replacement doses, it has a well-established safety profile. Most side effects are dose-dependent and reversible by reducing the dose. Long-term monitoring of blood sugar, IGF-1 levels, and overall health markers is recommended.
xDiabetic retinopathy (eye damage from diabetes)
xSevere respiratory illness or breathing problems
xKnown hypersensitivity to growth hormone or any excipients
xClosed epiphyses in children when used for growth
Decision Guide
Which isright for you?
Choose IGF-1 LR3 if...
Muscle growth and hypertrophy
Post-workout recovery
Body recomposition
Athletic performance enhancement
Choose Human Growth Hormone (HGH) if...
Body recomposition (building muscle while losing fat)
Anti-aging and longevity
Recovery from injury or surgery
Improved sleep quality