GHRP-6 vs Human Growth Hormone (HGH) vs IGF-1 LR3
A three-way comparison to help you find the right peptide for your research goals.
GHRP-6
Growth Hormone Releasing Peptide 6 (GHRP-6) is one of the first synthetic growth hormone secretagogues discovered. It stimulates significant GH release but is known for causing intense hunger.
Full details →Human Growth Hormone (HGH)
Human Growth Hormone (somatropin) is a 191-amino acid protein identical to naturally produced GH. FDA-approved for growth hormone deficiency, Turner syndrome, and other conditions. Widely used off-label for anti-aging and performance.
Full details →IGF-1 LR3
IGF-1 LR3 (Long R3 Insulin-like Growth Factor-1) is a modified version of IGF-1 with extended half-life and enhanced potency. The modifications prevent binding to IGF binding proteins, increasing bioavailability.
Full details →Side-by-Side Comparison
| Aspect | GHRP-6 | Human Growth Hormone (HGH) | IGF-1 LR3 |
|---|---|---|---|
| Mechanism | Acts as a ghrelin mimetic, binding to the GHS-R receptor in the pituitary and hypothalamus. Stimulates GH release and also significantly increases appetite by mimicking ghrelin's hunger-signaling effects. | Binds to GH receptors throughout the body, stimulating IGF-1 production in the liver. Promotes protein synthesis, fat metabolism, and cellular regeneration across multiple tissues. | Binds to IGF-1 receptors to promote protein synthesis, muscle growth, and fat metabolism. The LR3 modification (13 amino acid extension and arginine substitution) extends half-life from minutes to 20-30 hours. |
| Typical Dosage | Typical dosing: 100-300mcg administered 2-3 times daily. Often combined with GHRH peptides like CJC-1295 for synergistic effects. | Medical: 0.1-0.3mg/kg/week divided into daily doses. Anti-aging: 1-2 IU daily. Performance: 2-6 IU daily, sometimes higher. | Research protocols typically use 20-100mcg daily, often divided into multiple injections or administered bilaterally to target muscles. |
| Administration | Subcutaneous injection. Best administered on an empty stomach. The strong hunger response can be beneficial for those trying to gain weight but challenging for cutting. | Subcutaneous injection, preferably at night to mimic natural pulsatile release. Rotate injection sites. Store refrigerated. | Intramuscular injection (site-specific growth) or subcutaneous for systemic effects. Often cycled 4-6 weeks on, equal time off. |
| Side Effects | Intense hunger (most notable effect), water retention, increased cortisol and prolactin, tingling/numbness, and potential blood pressure changes. | Joint pain, water retention, carpal tunnel syndrome, potential insulin resistance, and acromegaly features with long-term high doses. | Hypoglycemia, joint pain, water retention, potential jaw/hand growth with extended use, and injection site reactions. |
| Best For |
What They Have in Common
GHRP-6, Human Growth Hormone (HGH), IGF-1 LR3 are all commonly used for:
Key Differences
Unique to Human Growth Hormone (HGH):
Unique to IGF-1 LR3:
Detailed Analysis
Commonalities
Both GHRP-6 and Human Growth Hormone (HGH) are commonly used for Muscle Growth, Recovery & Healing.
Which Should You Choose?
Human Growth Hormone (HGH) has stronger evidence for Recovery & Healing.
Commonalities
Both GHRP-6 and IGF-1 LR3 are commonly used for Muscle Growth, Recovery & Healing.
Which Should You Choose?
Both peptides have similar evidence levels for their shared goals. Your choice may depend on specific use case, availability, or personal response.
Commonalities
Both Human Growth Hormone (HGH) and IGF-1 LR3 are commonly used for Muscle Growth, Fat Loss, Recovery & Healing.
Which Should You Choose?
Human Growth Hormone (HGH) has stronger evidence for Fat Loss, Recovery & Healing.