Research & Education Only. All content on this page is for educational and research purposes only. Nothing here constitutes medical advice, a treatment recommendation, or an endorsement of any product or supplier. Always consult a qualified healthcare professional before making any health-related decision.

This library is a free research reference covering every peptide compound and GLP-1 weight loss drug featured on No Nonsense Fitness. Each entry links to a full research guide covering mechanism of action, preclinical and clinical data, relevant stacks, side effect profiles, and Irish regulatory context.

Click any compound below to open its full guide. Use the GLP-1 comparison table further down to compare the three main weight loss compounds side by side. All guides are free, no sign-up required.

All content for research and educational purposes only. Not medical advice.

GLP-1 & Weight Loss Compounds

GLP-1 receptor agonists, multi-receptor agonists, and fat-loss peptides studied for metabolic health and body composition. Includes approved medicines and compounds in clinical development.

Retatrutide

Triple agonist (GLP-1 / GIP / Glucagon). Phase 2 trial: 22.8% weight loss at 48 weeks — highest result published for any weight loss compound to date.

GLP-1 Triple Agonist Phase 3
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Semaglutide (Ozempic / Wegovy)

GLP-1 receptor agonist. STEP-1 trial: 14.9% weight loss at 68 weeks. Approved in Ireland for type 2 diabetes (Ozempic) and obesity (Wegovy).

GLP-1 Approved (T2D) Research Guide
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Tirzepatide (Mounjaro)

Dual agonist (GLP-1 / GIP). SURMOUNT-1 trial: 22.5% weight loss at 72 weeks. Approved in Ireland for type 2 diabetes as Mounjaro.

GLP-1 Dual Agonist Approved (T2D)
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AOD-9604

Modified fragment of human growth hormone studied specifically for fat metabolism. Targets fat cell lipolysis without the growth-promoting effects of HGH.

Fat Loss GH Fragment Research Guide
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HGH Fragment 176–191

C-terminal fragment of human growth hormone. Studied for selective fat-burning activity with no effect on blood glucose or insulin-like growth factor levels.

Fat Loss GH Fragment Research Guide
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Cagrilintide

Long-acting amylin analogue. In combination trials with semaglutide (CagriSema), has shown >25% weight loss results. Currently in Phase 3 development.

Amylin Phase 3 Research Guide
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Tesofensin

Triple monoamine reuptake inhibitor studied for obesity. Phase 2 trials showed 10.6% weight loss at 24 weeks. Distinct mechanism from GLP-1 compounds.

Weight Loss Neurotransmitter Research Guide
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Mazdutide

GLP-1 / Glucagon dual agonist developed in China. Phase 3 trials ongoing. Targets both appetite reduction and energy expenditure via dual receptor activation.

GLP-1 Dual Agonist Research Guide
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Recovery & Healing Peptides

Peptides studied for tissue regeneration, injury recovery, gut health, and wound healing. Research base largely preclinical; popular in sports science circles.

BPC-157

Studied for gut healing, tendon repair, and injury recovery. One of the most researched recovery peptides, with over 100 preclinical publications.

Recovery Gut Health Research Guide
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TB-500 (Thymosin Beta-4)

Tissue regeneration, wound healing, and flexibility research. Derived from a naturally occurring protein. Widely studied in recovery and anti-inflammatory research.

Recovery Tissue Repair Research Guide
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GHK-Cu

Copper peptide studied for collagen synthesis, skin repair, and wound healing. Also researched for anti-inflammatory and antioxidant properties.

Recovery Collagen Skin Repair
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ARA-290 (Cibinetide)

Innate repair receptor agonist. Studied for neuropathic pain, anti-inflammatory effects, and tissue protection. Has entered clinical trials for diabetic neuropathy.

Anti-Inflammatory Neuropathic Research Guide
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KPV

Tripeptide derived from alpha-MSH. Studied for potent anti-inflammatory effects, gut healing, and reduction of inflammatory bowel disease markers in preclinical models.

Anti-Inflammatory Gut Health Research Guide
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LL-37

Human cathelicidin antimicrobial peptide. Studied for broad-spectrum antimicrobial activity, wound healing, and immune modulation. Naturally produced in skin and respiratory tissue.

Antimicrobial Wound Healing Research Guide
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MGF (Mechano Growth Factor)

IGF-1 splice variant released by muscle after mechanical loading. Studied for satellite cell activation, muscle repair, and recovery acceleration following resistance exercise.

Muscle Repair GH Axis Research Guide
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PEG-MGF

Pegylated form of MGF engineered for extended half-life. Studied for muscle satellite cell activation; pegylated form has a much thinner published evidence base than native MGF.

Muscle Repair GH Axis Research Guide
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Follistatin 344

Myostatin-binding protein and activin antagonist. Studied in animal models for muscle growth via myostatin inhibition; human injectable data is sparse.

Muscle Growth Myostatin Inhibitor Research Guide
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Thymosin Alpha-1

Immune-modulating peptide derived from the thymus. Studied for T-cell activation, antiviral response, and immune system support. Approved in some countries for hepatitis B/C.

Immune T-Cell Research Guide
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Growth Hormone Axis Peptides

GHRPs and GHRH analogues studied for growth hormone release, lean mass, sleep quality, and recovery. Not approved medicines; research use only.

Ipamorelin

GHRP (growth hormone releasing peptide). Studied for GH pulse release, sleep quality improvement, and lean mass research. Considered selective with a low side effect profile in studies.

GHRP GH Axis Research Guide
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Sermorelin

GHRH analogue. Growth hormone secretagogue studied for anti-aging effects, lean mass, and recovery. Shorter half-life than CJC-1295.

GHRH GH Axis Research Guide
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MK-677 (Ibutamoren)

Oral GH secretagogue. Studied for lean mass, sleep quality, and IGF-1 elevation. Taken orally, not injected — unusual among GH-axis compounds.

GH Secretagogue Oral Research Guide
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IGF-1

Insulin-like Growth Factor 1. Key downstream mediator of GH signalling. Studied for muscle hypertrophy, recovery, and anabolic effects in preclinical research.

GH Axis Anabolic Research Guide
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CJC-1295 (No DAC)

GHRH analogue with a shorter half-life than the DAC variant, preserving natural pulsatile GH release. Standalone research guide (see also the Ipamorelin stack guide below).

GHRH GH Axis Research Guide
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CJC-1295 / Ipamorelin Stack

GHRH analogue combined with Ipamorelin for synergistic GH pulse release. Extended half-life (no DAC variant) allows dosing flexibility. One of the most popular GH-axis stacks in research.

GHRH GH Axis Stack Guide
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GHRP-2

Second-generation growth hormone releasing peptide. Strong GH pulse stimulator studied for lean mass, appetite increase, and IGF-1 elevation. More potent ghrelin mimetic than GHRP-6.

GHRP GH Axis Research Guide
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GHRP-6

First-generation growth hormone releasing peptide. Strong appetite stimulant alongside GH release. Widely used in research; often stacked with a GHRH analogue for synergy.

GHRP GH Axis Research Guide
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Tesamorelin

Synthetic GHRH analogue. FDA-approved for HIV-associated lipodystrophy; studied for visceral fat reduction, cognitive function, and GH deficiency. One of the better-evidenced GHRH compounds.

GHRH GH Axis FDA Approved
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HGH (Somatropin)

Recombinant human growth hormone. Approved medicine for GH deficiency and related conditions; off-label anti-ageing/bodybuilding use is not an approved indication anywhere.

GH Axis Approved Medicine Research Guide
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IGF-1 LR3

Long R3 IGF-1 analogue with amino acid substitutions extending half-life versus native IGF-1. Studied for anabolic/hypertrophy research; largely grey-market human use data.

GH Axis Anabolic Research Guide
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Cognitive, Metabolic & Longevity

Peptides studied for cognitive enhancement, metabolic function, cellular energy, and longevity. Includes nootropic peptides and mitochondrial compounds.

Semax

Russian nootropic peptide derived from ACTH. Studied for BDNF upregulation, cognitive function, focus, and stress resilience. Used clinically in Russia for stroke recovery.

Cognitive BDNF Research Guide
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Selank

Anxiolytic peptide derived from tuftsin. Studied for anxiety reduction, cognitive focus, and immune modulation. Used clinically in Russia as an anti-anxiety compound.

Cognitive Anxiolytic Research Guide
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Epithalon

Tetrapeptide studied for telomere elongation, longevity research, and pineal gland function. One of the most studied compounds in aging biology research.

Longevity Telomeres Research Guide
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NAD+

Nicotinamide adenine dinucleotide. Essential coenzyme in cellular energy metabolism. Studied for mitochondrial function, DNA repair, and aging mechanisms.

Longevity Metabolic Research Guide
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MOTS-C

Mitochondria-derived peptide. Studied for metabolic function, insulin sensitivity, and exercise performance. Encodes in mitochondrial DNA — a unique class of signalling peptide.

Longevity Metabolic Mitochondrial
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Humanin

Mitochondria-derived peptide. Studied for cytoprotection, neuroprotection, insulin sensitivity, and age-related decline. Levels naturally decline with age in human studies.

Longevity Neuroprotective Research Guide
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SS-31 (Elamipretide)

Mitochondria-targeting antioxidant peptide. Studied for mitochondrial dysfunction, cardioprotection, and age-related energy decline. Targets the inner mitochondrial membrane directly.

Longevity Mitochondrial Research Guide
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DSIP (Delta Sleep-Inducing Peptide)

Endogenous neuropeptide studied for sleep regulation, stress resilience, and hormone modulation. Isolated from rabbit cerebral blood during sleep — one of the earliest identified sleep peptides.

Cognitive Sleep Research Guide
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5-Amino-1MQ

NNMT inhibitor studied for fat cell metabolism, energy expenditure, and weight management. Targets the nicotinamide N-methyltransferase pathway involved in obesity and metabolic disease.

Metabolic NNMT Inhibitor Research Guide
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AICAR

AMPK activator studied as an exercise mimetic. Preclinical research showed improved endurance and fat oxidation without exercise. Acts on the same energy-sensing pathway activated by physical training.

Metabolic AMPK Research Guide
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FOXO4-DRI (Proxofim)

Senolytic peptide that disrupts the FOXO4-p53 interaction in senescent cells. Built on a landmark 2017 Cell paper; preclinical only, no human trials.

Longevity Senolytic Research Guide
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Glutathione

Endogenous tripeptide antioxidant. Substantial real clinical evidence base for oxidative stress and liver detoxification contexts; also used off-label for skin brightening.

Antioxidant Research Guide
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FGL Peptide

Neural cell adhesion molecule (NCAM) mimetic peptide. Studied for memory and synaptic plasticity in preclinical/animal models; essentially no human data.

Cognitive NCAM Mimetic Research Guide
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P21 (P021)

PKC epsilon activator studied for memory and cognitive enhancement in Alzheimer's-model research. Preclinical only.

Cognitive PKC Activator Research Guide
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PE-22-28

Spadin-derived peptide fragment; TREK-1 potassium channel blocker studied for antidepressant effects in rodent models. Preclinical only, thin published evidence base.

Cognitive TREK-1 Blocker Research Guide
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Peptide Bioregulators

Short peptide bioregulators developed from Khavinson research. Studied for organ-specific and tissue-specific regeneration. Primarily Russian clinical research base.

Pinealon

Pineal gland bioregulator. Studied for sleep cycle regulation, neuroprotection, and age-related cognitive decline. Contains three amino acids (Glu-Asp-Arg).

LongevitySleepResearch Guide
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Cortagen

Brain cortex bioregulator. Studied for neuroprotection, cognitive restoration, and support following brain injury or aging-related cortical decline.

CognitiveNeuroprotectiveResearch Guide
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Cardiogen

Cardiac muscle bioregulator. Studied for myocardial protection and cardiovascular tissue support. Tetrapeptide targeting cardiac cell differentiation in preclinical research.

CardiovascularLongevityResearch Guide
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Thymalin

Thymus-derived peptide bioregulator. Studied for immune restoration, T-cell function, and age-related immunosenescence. Longer clinical record than most immune peptides.

ImmuneLongevityResearch Guide
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Vesugen

Vascular bioregulator. Studied for endothelial function, microcirculation, and blood vessel integrity. Used in Russian gerontology research for vascular aging.

VascularLongevityResearch Guide
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Cartalax

Cartilage and connective tissue bioregulator. Studied for joint repair, cartilage regeneration, and musculoskeletal support in aging populations.

Joint HealthLongevityResearch Guide
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Chonluten

Lung and bronchial bioregulator. Studied for respiratory tissue support, bronchial function, and chronic lung disease management. Particularly studied in smoking-related lung conditions.

RespiratoryLongevityResearch Guide
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Retinalamin

Retinal bioregulator. Studied for retinal cell restoration and age-related macular degeneration support. Contains peptides specific to retinal tissue.

OcularLongevityResearch Guide
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Crystagen

Lymphoid/immune tissue bioregulator from the same Khavinson family as Thymalin and Vesugen. Evidence base is Russian preclinical/clinical, limited by Western standards.

ImmuneLongevityResearch Guide
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Testagen

Testicular/reproductive tissue bioregulator from the same Khavinson family. Evidence base is Russian preclinical/clinical, limited by Western standards.

ReproductiveLongevityResearch Guide
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Hormonal & Specialty Peptides

Compounds spanning reproductive endocrinology, pigmentation, appetite, and metabolic signalling that don't fit the categories above. Mix of approved medicines and research-only compounds.

PT-141 (Bremelanotide)

Melanocortin receptor (MC4R) agonist. FDA-approved as Vyleesi for hypoactive sexual desire disorder in the US; not approved in Ireland/EU.

MelanocortinFDA Approved (US)Research Guide
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Kisspeptin

KISS1R agonist regulating the hypothalamic-pituitary-gonadal axis. Substantial human trial base (Imperial College London) despite no regulatory approval.

ReproductiveResearch Guide
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Melanotan I (Afamelanotide)

Alpha-MSH analogue. FDA/EMA-approved as Scenesse for erythropoietic protoporphyria photoprotection, with real regulatory history distinct from grey-market use.

MelanocortinFDA/EMA ApprovedResearch Guide
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Melanotan II

Non-selective melanocortin agonist studied for tanning and libido effects. Not approved anywhere; documented safety concerns with unregulated grey-market use.

MelanocortinUnapprovedResearch Guide
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HCG

Human Chorionic Gonadotropin. Approved medicine for fertility and hypogonadotropic hypogonadism; also used off-label in TRT protocols for testicular function preservation.

ReproductiveApproved MedicineResearch Guide
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Oxytocin

Neuropeptide hormone. Approved medicine for labour induction/postpartum haemorrhage; extensive separate research literature on social bonding, trust, and anxiety.

NeuropeptideApproved MedicineResearch Guide
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RU58841

Non-steroidal topical antiandrogen studied for androgenetic alopecia. Local androgen receptor antagonism at the scalp — development discontinued, no completed human trials.

HairTopicalResearch Guide
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Hair Health Stack (GHK-Cu + RU58841)

Pairs a local antiandrogen (RU58841) with a tissue-support copper peptide (GHK-Cu) — hormonal driver and follicle environment addressed separately. Research overview, not a documented personal protocol.

HairStack Guide
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SLU-PP-332

Synthetic ERR agonist "exercise mimetic" (a small molecule, not a peptide). Saint Louis University research; mouse-only endurance/metabolism data.

Small MoleculeERR AgonistResearch Guide
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GLP-1 Compound Quick Comparison

* Retatrutide 48-week figure is from Phase 2 data. Phase 3 results pending. All trial results are at highest studied doses in placebo-controlled trials.

Compound Receptors Best Trial Result Trial Duration Status (Ireland)
Semaglutide GLP-1 14.9% weight loss 68 weeks Approved (T2D)
Tirzepatide GLP-1 + GIP 22.5% weight loss 72 weeks Approved (T2D)
Retatrutide GLP-1 + GIP + Glucagon 22.8% weight loss* 48 weeks* Phase 3

Want to understand which compounds suit your goals? Our free tools can help you calculate dosing, track macros, and plan your approach — all evidence-based, all free.

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