A structured overview of the six major research peptide families — their receptor targets, mechanisms of action, key compounds, and a goal-based decision matrix to guide your research focus.
Research peptides are not a monolithic category. They span six distinct biochemical families, each acting on different receptor systems, producing different downstream effects, and serving different research applications. Understanding which family a compound belongs to is the first step in designing a coherent research protocol — before considering individual compounds, dosing, or stacking strategies.
The six families covered in this guide are: GHRH analogues (pituitary GH axis stimulation), GHRP peptides (ghrelin receptor-mediated GH release), GLP-1 receptor agonists (metabolic and glycemic regulation), recovery and repair peptides (tissue regeneration), longevity peptides (cellular aging and mitochondrial function), and cognitive/nootropic peptides (neuroprotection and CNS modulation).
Research context: All compounds discussed on this page are research-grade peptides intended for laboratory and preclinical research purposes only. They are not approved for human use (except where FDA approval is noted) and should not be interpreted as medical advice.
Each family card summarizes the receptor target, mechanism, key compounds, and primary research applications. Click the hub link to access the full family reference guide.
Growth Hormone Releasing Hormone
Growth Hormone Releasing Peptides
Glucagon-Like Peptide-1 Receptor Agonists
Tissue Regeneration & Healing
Cellular Health & Senescence
Neuroprotection & CNS Enhancement
A side-by-side reference comparing the six families across the most clinically relevant dimensions.
| Family | Receptor | GH Effect | Cortisol | FDA Approved | Stackable |
|---|---|---|---|---|---|
| GHRH Analogues | GHRH-R | High (pulsatile) | None | Tesamorelin | Yes (+ GHRP) |
| GHRP Peptides | GHS-R1a | High (synergistic) | Minimal–Moderate | None | Yes (+ GHRH) |
| GLP-1 Agonists | GLP-1R | None | None | Sema, Tirz | Limited |
| Recovery Peptides | Multiple (GF) | None | None | None | Yes (BPC + TB-500) |
| Longevity Peptides | Mitochondrial | None | None | None | Yes |
| Cognitive Peptides | Sigma-1, DA | None | None | None (Russia) | Limited |
Select your primary research goal to identify the most appropriate peptide family and lead compound.
Research protocols frequently combine compounds from different families to achieve synergistic or complementary effects. The most well-characterized cross-family combination is the GHRH + GHRP stack, which produces 3–5× more GH than either class alone by simultaneously stimulating two independent receptor pathways. This synergy is the pharmacological basis for the ubiquitous CJC-1295 + Ipamorelin research protocol.
The gold standard GH axis protocol. CJC-1295 (GHRH-R) + Ipamorelin (GHS-R1a) produces 3–5× synergistic GH output.
Dosage Guide →BPC-157 (systemic repair) + TB-500 (actin polymerization) addresses both local and systemic tissue regeneration simultaneously.
TB-500 Guide →Epithalon (telomerase) + MOTS-c (mitochondrial) + SS-31 (cardiolipin) targets three independent aging pathways in parallel.
Longevity Hub →Each family hub contains full compound profiles, mechanism deep-dives, dosage references, and comparison guides. Start with the family most relevant to your research focus.
Research peptides are broadly categorized into six families: GHRH analogues (Sermorelin, CJC-1295, Tesamorelin), GHRP peptides (Ipamorelin, GHRP-2, GHRP-6), GLP-1 receptor agonists (Semaglutide, Tirzepatide), recovery and repair peptides (BPC-157, TB-500), longevity peptides (Epithalon, MOTS-c, SS-31), and cognitive/nootropic peptides (Selank, Semax, Dihexa). Each family acts on distinct receptor systems and serves different research applications.
GHRH analogues (like Sermorelin and CJC-1295) act on the GHRH receptor in the pituitary to stimulate GH synthesis and release. GHRP peptides (like Ipamorelin and GHRP-2) act on the ghrelin receptor (GHS-R1a) via a completely separate pathway. When combined, they produce 3–5× more GH than either class alone — a synergy that makes GHRH+GHRP stacking the most common GH-axis research protocol.
For researchers new to peptides, GHRH analogues (particularly Sermorelin) are the most studied and best-characterized entry point. They have the longest clinical history, a well-understood safety profile, and a straightforward subcutaneous injection protocol. BPC-157 is also commonly studied by beginners due to its broad tissue-repair applications and extensive preclinical safety data.
Yes — cross-family stacking is common in research protocols. The most studied combination is GHRH + GHRP (e.g., CJC-1295 + Ipamorelin), which produces synergistic GH release. GLP-1 agonists are generally studied in isolation due to their distinct metabolic mechanism. Recovery peptides like BPC-157 and TB-500 are frequently combined. Always review the individual mechanism and half-life profiles before combining peptide families.
Yes — Tesamorelin (Egrifta) is FDA-approved for HIV-associated lipodystrophy, and Semaglutide (Ozempic/Wegovy) and Tirzepatide (Mounjaro/Zepbound) are FDA-approved for type 2 diabetes and obesity. The remaining peptide families (GHRP, recovery, longevity, cognitive) are not FDA-approved and are available for research purposes only.
Medical Disclaimer: All content on this site is for educational and research purposes only. Research peptides are not FDA-approved for human use. Always consult a qualified healthcare professional before considering any peptide or supplement protocol. Nothing on this site constitutes medical advice, diagnosis, or treatment.