Compare Peptides
Select any two compounds for a side-by-side comparison of mechanism, uses, risks, and FDA regulatory status.
Popular comparisons
IGF-1 LR3
Insulin-like Growth Factor-1 Long R3, Long R3 IGF-1
GHRP-6
Growth Hormone Releasing Peptide-6, His-D-Trp-Ala-Trp-D-Phe-Lys-NH2
A synthetic analog of insulin-like growth factor-1 (IGF-1) with an extended half-life due to a modified arginine-3 sequence. IGF-1 is naturally produced in the liver in response to growth hormone. The LR3 variant is approximately 3x more potent than native IGF-1 and resists binding to IGF-binding proteins, extending its activity.
One of the original synthetic growth hormone secretagogues, developed in the 1980s. A hexapeptide that strongly stimulates GH release through ghrelin receptor activation. Historically significant as the compound that led to the discovery of the ghrelin receptor and the development of the entire GHS drug class.
Binds to IGF-1 receptors throughout the body, stimulating cell growth, proliferation, and differentiation. Promotes protein synthesis, glucose uptake, and fat oxidation. Activates the PI3K/Akt/mTOR pathway — the primary anabolic signaling cascade. Unlike GH secretagogues, IGF-1 LR3 acts directly at the tissue level rather than through the pituitary.
Binds to ghrelin receptors (GHS-R1a) in the pituitary and hypothalamus, triggering pulsatile GH release. Also stimulates appetite significantly through central ghrelin receptor activation — more so than most other GHS peptides. Increases IGF-1 levels downstream of GH release.
- Muscle growth and hypertrophy
- Recovery from injury
- Fat loss
- Anti-aging protocols
- Athletic performance enhancement
- Growth hormone optimization
- Muscle recovery and growth
- Fat loss
- Appetite stimulation (useful in wasting conditions)
- Anti-aging protocols
- Hypoglycemia (blood sugar drop) — significant risk, especially post-workout
- Potential tumor growth promotion (IGF-1 pathway implicated in cancer)
- Acromegaly-like effects with chronic high-dose use
- Joint pain
- Water retention
- Limited long-term human safety data
- High abuse potential in athletic contexts
- Significant appetite stimulation (can undermine fat loss goals)
- Cortisol and prolactin elevation
- Water retention
- Desensitization with frequent dosing
- Tingling and numbness
- Limited long-term human safety data
Not FDA-approved and not on any compounding list. Available as a research chemical. One of the more potent anabolic peptides — the hypoglycemia risk is real and requires careful dosing. Not affected by the 2026 regulatory changes.
Reclassified to Category 1 in February 2026 as part of the HHS announcement restoring compounding access. Not affected by the April 15, 2026 Category 2 removal action. Available through licensed 503A compounding pharmacies with a physician prescription. Often used in combination with GHRH analogs like CJC-1295.
- Growth hormone-releasing peptides and their analogs
1998 · PubMed
This comparison is for educational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional before starting any peptide therapy.