Encyclopedia

The peptide reference

50 compounds in plain English — search or filter by category and development stage. No hype, no affiliate links.

Educational only — not medical advice. Many compounds here are not FDA-approved and/or are WADA-prohibited. Talk to your provider.

Showing 50 of 50

Preclinical
5-Amino-1MQ
Metabolic & Weight · 5-amino-1-methylquinolinium
5-Amino-1MQ is a small molecule, not a peptide — it has no amino-acid sequence and is a membrane-permeable inhibitor of the enzyme nicotinamide N-methyltransferase (NNMT). By inhibiting NNMT, it is proposed to shift cellular metabolism (raising NAD+ and SAM in fat cells) and increase adipocyte energy expenditure. All of the supporting evidence is preclinical: in diet-induced obese mice, NNMT inhibition reduced body weight and fat mass without changing food intake. There are no published human clinical trials, and it is not FDA-approved. Any human benefit claims are extrapolated from animal data and should be treated as unproven.
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Early human
ACE-031
Growth & Muscle · ACVR2B-Fc
ACE-031 (ramatercept) is a recombinant fusion protein combining the extracellular domain of the activin receptor type IIB (ActRIIB) with an antibody Fc region, designed to act as a 'decoy' that soaks up myostatin and related TGF-beta proteins to release the brake on muscle growth. It is not FDA-approved, and importantly its development was discontinued: a Phase 2 trial in boys with Duchenne muscular dystrophy was halted in 2011 over safety signals (nosebleeds and small dilated blood vessels, telangiectasias, attributed to off-target effects on related signaling proteins), and the developers ended the program in 2013. So while early data suggested it could increase muscle and lean mass, the human story is one of a stopped program rather than a proven therapy. Any current 'ACE-031' offered for sale is unapproved.
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Preclinical
Adipotide
Metabolic & Weight · FTPP
Adipotide is a synthetic chimeric peptide designed to selectively destroy the blood supply of white fat tissue: a homing sequence targets prohibitin/ANXA2 on the vasculature feeding white adipose tissue, linked to a proapoptotic (cell-death-triggering) sequence, so the targeted blood vessels regress and fat cells die. In preclinical studies it produced striking weight loss — roughly 30% in obese mice and about 11% body-weight reduction in obese rhesus monkeys, with improved insulin sensitivity. However, it never demonstrated a viable human profile: an early-phase human (Phase 1) trial was undertaken but development was halted, with nephrotoxicity (kidney injury / renal lesions) a key concern, and clinical development was ultimately discontinued. There is no credible human efficacy or safety evidence supporting use, and any marketing of it for weight loss is unproven and inadvisable.
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FDA-approved
Afamelanotide
Hormonal & Sexual · Scenesse
Afamelanotide is a synthetic analogue of alpha-melanocyte-stimulating hormone (alpha-MSH) that activates melanocortin-1 receptors (MC1R) to stimulate eumelanin production in the skin, increasing photoprotection. It is the approved-drug form of the molecule also known as Melanotan-1, and it is FDA-approved (as Scenesse, 2019; EU-approved 2014) for prevention of phototoxicity in adults with erythropoietic protoporphyria (EPP), a rare light-sensitivity disorder. Approval is supported by randomized controlled trials: in pooled Phase 3 data, treated EPP patients tolerated substantially more pain-free time in direct sunlight than placebo. It is delivered as a physician-administered subcutaneous implant under specialist supervision. Its approval is indication-specific — it is the melanocortin cousin of the unapproved cosmetic 'Melanotan' products, and any tanning or off-label cosmetic use is not an approved use.
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Limited human data
AOD-9604
Metabolic & Weight · Anti-Obesity Drug 9604
AOD-9604 is a synthetic fragment of human growth hormone (amino acids 176–191) designed to isolate the fat-metabolism (lipolytic) portion of the molecule without the broader GH effects — notably, it is generally reported NOT to raise IGF-1. It is marketed for fat loss. The human evidence is modest: in a 23-week randomized clinical trial, participants on AOD-9604 1 mg/day lost on average about 2.8 kg vs about 0.8 kg on placebo. Importantly, AOD-9604 failed to show sufficient efficacy in later obesity development, and there is no robust, high-quality human evidence that adding it to a GLP-1/GIP therapy produces meaningful additional fat loss. Claims should be treated cautiously.
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Limited human data
ARA-290 (Cibinetide)
Recovery & Immune · Cibinetide
ARA-290 (cibinetide) is an 11-amino-acid peptide derived from the tissue-protective region of erythropoietin (EPO). It is engineered to activate the 'innate repair receptor' (a heteromer of the EPO receptor and the beta-common receptor) to produce anti-inflammatory and tissue-protective effects WITHOUT stimulating red-blood-cell production. Unlike most peptides in this dataset it has genuine human trial data: in a randomized, double-blind, placebo-controlled pilot in sarcoidosis patients with small-fiber neuropathy (22 patients, 28 days of dosing), the ARA-290 group showed a significant improvement in neuropathy symptom score versus placebo, with no rise in hemoglobin and a clean short-term safety profile. It holds FDA Orphan Drug designation for sarcoidosis-associated neuropathy and has been studied in diabetic neuropathy. As of 2026 it remains investigational and is not approved for marketing in any jurisdiction; the efficacy data, while encouraging, comes from small early-phase studies.
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Early human
BPC-157
Recovery & Immune · Body Protection Compound 157
BPC-157 is a 15-amino-acid peptide studied primarily in animal models, where it has shown effects on angiogenesis (new blood-vessel formation), tendon/ligament and gut healing, and modulation of inflammatory signaling. It is one of the most popular 'recovery' peptides among athletes, but the human evidence is very thin: a 2025 systematic review in the American Journal of Sports Medicine screened 544 articles and found only 1 clinical study met inclusion criteria, with the rest being preclinical animal models. As of early 2026 only about three small human pilot studies exist, and fewer than ~30 people have been studied across published human trials. It is not FDA-approved for any indication. Any claims about its benefits in humans should be treated as preliminary and unproven.
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Limited human data
Cagrilintide
Metabolic & Weight · AM833
Cagrilintide is an investigational once-weekly peptide that acts as a long-acting analog of the hormone amylin, promoting satiety and slowed gastric emptying through amylin and calcitonin receptors. It is most studied in combination with semaglutide as the fixed-dose product CagriSema, where co-administration produced greater weight loss than either component alone in published Phase 2 work. The human evidence base is meaningful but still incomplete: as of 2026, Novo Nordisk has reported Phase 3 (REDEFINE) results and filed for FDA approval of CagriSema, but cagrilintide is NOT yet FDA-approved as a stand-alone agent or in combination. It is a true peptide.
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Limited human data
Cerebrolysin
Cognitive & Longevity · FPF-1070
Cerebrolysin is a proprietary mixture of low-molecular-weight neuropeptides and free amino acids derived from purified porcine brain, marketed as having neurotrophic, neuroprotective effects. It is approved and used clinically in many countries (Eastern Europe, Asia, and elsewhere) for stroke, dementia, and traumatic brain injury, but it is NOT FDA-approved in the US. Importantly, independent Cochrane reviews have judged the overall evidence to be of very low certainty: pooled trials in vascular dementia and stroke do not clearly establish a clinically meaningful benefit, and at least one review flagged a possible increase in non-fatal serious adverse events. The honest summary is that benefit remains unproven by rigorous independent standards.
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Limited human data
CJC-1295
Growth & Muscle · CJC-1295 with DAC
CJC-1295 is a synthetic analog of GHRH that stimulates the pituitary to release growth hormone (GH). The 'with DAC' (Drug Affinity Complex) version has a markedly extended half-life (on the order of days vs. minutes/hours), producing a sustained rise in GH and IGF-1. A published human study (Walker et al., 2006, Journal of Clinical Endocrinology & Metabolism) showed CJC-1295 with DAC produced dose-dependent increases in plasma GH and IGF-1 lasting several days, with mean IGF-1 rising roughly 1.5- to 3-fold above baseline in healthy adults. It is commonly paired with ipamorelin. Despite pharmacologic data, it is not FDA-approved for human use and is prohibited in sport.
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Preclinical
Dihexa
Cognitive & Longevity · N-hexanoic-Tyr-Ile-(6) aminohexanoic amide
Dihexa is a synthetic peptide derived from angiotensin IV, engineered to cross the blood-brain barrier and promote the formation of new synapses. In cell and rodent studies it has shown potent procognitive and synaptogenic effects that appear to depend on activation of the hepatocyte growth factor (HGF)/c-Met system. Despite striking laboratory potency, the published evidence is essentially entirely preclinical — there are no adequate controlled human efficacy trials and it is NOT FDA-approved. Any human cognitive benefit is unproven, and the marketing comparisons to BDNF refer to in-vitro potency, not demonstrated clinical effect.
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Early human
DSIP (Delta Sleep-Inducing Peptide)
Cognitive & Longevity · delta sleep-inducing peptide
DSIP (delta sleep-inducing peptide) is a naturally occurring nine-amino-acid neuropeptide first isolated in 1974 from the blood of sleeping rabbits, named for its ability to induce delta-wave (deep) EEG activity when infused into animal brains. Its precise receptor and mechanism in humans remain poorly defined — proposed actions include modulation of NMDA receptors and stress/glucocorticoid pathways. It is marketed for sleep, stress, and recovery, but the human evidence is limited, old, and inconsistent: some small studies suggest effects on sleep or stress measures, while others do not, and no rigorous large trials establish efficacy. It is not FDA-approved, and its long-term safety in humans has not been characterized. Claims should be treated as preliminary and unproven.
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FDA-approved
Dulaglutide
Metabolic & Weight · Trulicity
Dulaglutide is a once-weekly injectable GLP-1 receptor agonist built as a GLP-1 analog fused to an antibody (IgG4-Fc) fragment, which extends its half-life to about five days. It is FDA-approved for type 2 diabetes and is supported by the large AWARD Phase 3 program plus the REWIND cardiovascular outcomes trial, which showed a statistically significant reduction in major adverse cardiovascular events. It is marketed by Eli Lilly as Trulicity. Approval is indication-specific; it is not approved as a stand-alone obesity drug, and weight loss with dulaglutide is generally more modest than with newer agents. It is a true peptide-based biologic.
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Limited human data
Elamipretide (SS-31)
Cognitive & Longevity · SS-31
Elamipretide (SS-31) is a small mitochondria-targeting peptide that binds cardiolipin in the inner mitochondrial membrane, helping stabilize cristae structure and improve mitochondrial energy production while reducing oxidative stress. It is the most clinically advanced compound on this list: it reached Phase 2/3 testing for several mitochondrial conditions, and in September 2025 the FDA approved it (brand name Forzinity) for Barth syndrome, a rare genetic mitochondrial disorder. However, its trial record is mixed — the Phase 3 MMPOWER-3 study in primary mitochondrial myopathy did not meet its primary endpoints (6-minute walk distance and fatigue). So while there is now an FDA-approved use in one rare disease, broader 'mitochondrial health' or anti-aging claims are not supported by successful trials.
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Early human
Epitalon
Cognitive & Longevity · Epithalon
Epitalon (Epithalon) is a synthetic tetrapeptide based on a pineal-gland peptide, developed in Russia and promoted as an anti-aging or 'longevity' compound. The central claim — that it activates telomerase and lengthens telomeres — comes mainly from Russian laboratory studies and a small number of Russian clinical reports, with very limited independent replication. While there is some human data (e.g., small trials in retinitis pigmentosa and circadian/melatonin regulation), the body of evidence for anti-aging benefit is dominated by one research group and remains preliminary. It is NOT FDA-approved, and longevity claims should be regarded as unproven.
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Early human
Follistatin
Growth & Muscle · FST
Follistatin is a naturally occurring glycoprotein that binds and neutralizes myostatin and activin — TGF-beta family proteins that normally restrain muscle growth — so blocking them is expected to favor muscle gain. It is not FDA-approved for any indication. The most rigorous human work has used AAV-delivered follistatin gene therapy (AAV1-FS344) in small Phase 1/2a trials for Becker muscular dystrophy and sporadic inclusion body myositis, which reported some six-minute-walk improvements and favorable muscle histology with no serious adverse events, but these were tiny, early-stage studies in disease populations, not evidence for healthy-person muscle building. Injectable 'follistatin-344' peptide products sold online are a different, unproven proposition with essentially no controlled human efficacy data.
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Preclinical
FOXO4-DRI
Cognitive & Longevity · FOXO4-D-Retro-Inverso peptide
FOXO4-DRI is an engineered D-retro-inverso peptide designed to act as a senolytic — a compound that selectively kills senescent ('zombie') cells. It works by disrupting the interaction between the FOXO4 protein and p53, which normally keeps senescent cells alive; freeing p53 triggers apoptosis preferentially in those cells. In the landmark 2017 work and subsequent animal studies, treated aged mice showed improvements such as restored fur density, better kidney-function markers, and increased activity. All efficacy data, however, come from cell and animal experiments — there are no human clinical trials, and it is NOT FDA-approved. Any anti-aging benefit in people is entirely unproven.
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Early human
GHK-Cu
Recovery & Immune · Copper Tripeptide-1
GHK-Cu is the copper complex of GHK (glycyl-L-histidyl-L-lysine), a tripeptide that occurs naturally in human plasma — roughly 200 ng/mL at age 20, declining to about 80 ng/mL by age 60 — and binds copper with high affinity. In cell and animal models it stimulates collagen, glycosaminoglycan and proteoglycan synthesis, modulates matrix metalloproteinases, has antioxidant activity, and has been reported to up- and down-regulate thousands of human genes. Two very different products are sold under this name and should not be conflated: a TOPICAL cosmetic form (creams/serums) widely available over the counter for skin, and an INJECTABLE 'research' form. The strongest human data is for the topical cosmetic use — small placebo-controlled facial studies (typically ~40–70 women over ~12 weeks) reporting improvements in wrinkle depth, skin density and firmness. There are no large controlled human trials supporting injectable/systemic GHK-Cu for wound healing, hair, or 'anti-aging,' so those claims should be treated as unproven.
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Limited human data
GHRP-2
Growth & Muscle · Pralmorelin
GHRP-2 (pralmorelin) is a synthetic hexapeptide that acts as an agonist at the ghrelin receptor (GHS-R1a), prompting the pituitary to release a pulse of growth hormone. It is not FDA-approved for any indication; its only regulatory approval is in Japan, where it has been used as a diagnostic agent to test for growth hormone deficiency, not as a treatment. Marketed claims about muscle gain, fat loss, and recovery rest largely on its acute GH-raising effect plus animal and small human pharmacology studies, not on controlled efficacy trials for those outcomes. It also tends to stimulate appetite and can transiently raise cortisol and prolactin.
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Early human
GHRP-6
Growth & Muscle · Growth Hormone Releasing Peptide-6
GHRP-6 is a hexapeptide growth hormone secretagogue that stimulates GH release via the ghrelin receptor. Among the GHRPs it is notable for strongly stimulating appetite, and it tends to raise cortisol and prolactin more than the more selective ipamorelin. It has been used in endocrinology research as a GH-stimulation agent. It is not FDA-approved for human use, is sold mainly as a research chemical, and is prohibited in sport. Marketed performance and physique claims are not supported by robust controlled human outcome trials.
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FDA-approved
Gonadorelin (GnRH)
Hormonal & Sexual · GnRH
Gonadorelin is a synthetic decapeptide structurally identical to natural gonadotropin-releasing hormone (GnRH/LHRH). Acting on pituitary GnRH receptors, pulsatile gonadorelin stimulates the anterior pituitary to release luteinizing hormone (LH) and follicle-stimulating hormone (FSH). It has a genuine FDA-approval history: the human product Factrel was approved for diagnostic evaluation of pituitary gonadotropic (LH-reserve) function — helping distinguish pituitary from hypothalamic causes of hypogonadotropic states — and a pulsatile form (Lutrepulse) was used to induce ovulation. However, the branded human products were discontinued in the US for commercial reasons, so no FDA-approved human gonadorelin product is currently marketed; what is sold today is largely compounded and not FDA-approved. Its action is mechanistically well established, but modern popular 'fertility/testosterone support' marketing outpaces current approved availability.
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Limited human data
Hexarelin
Growth & Muscle · Examorelin
Hexarelin (examorelin) is a synthetic hexapeptide growth-hormone-releasing peptide that activates the ghrelin receptor (GHS-R1a) to trigger growth hormone release, and is often described as one of the more potent GHRPs for an acute GH spike. It is not FDA-approved for any indication and has only been studied in small, mostly short-term human pharmacology and cardiovascular research settings. A notable limitation is that the GH response tends to wane with repeated use as the receptor desensitizes, and it can raise cortisol and prolactin. Claims around muscle growth, fat loss, and heart-protective effects remain preliminary and unproven for routine use.
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Early human
Humanin
Cognitive & Longevity · HN
Humanin is a small mitochondria-encoded peptide first identified as a factor that protects neurons from Alzheimer's-disease-related toxicity. Mechanistically it is well studied in cells and animals: it binds IGFBP-3 to modulate IGF-1 signaling, interacts with the pro-apoptotic protein BAX, and activates STAT3, producing broad cytoprotective and metabolic effects in models. Observational human studies show circulating humanin declines with age and tracks with metabolic and cognitive measures. However, there are no adequate interventional human efficacy trials of exogenous humanin, no established human dosing or pharmacokinetics, so its therapeutic value in people remains unproven. It is NOT FDA-approved.
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Preclinical
IGF-1 LR3
Growth & Muscle · Long R3 IGF-1
IGF-1 LR3 is a synthetic, lengthened analog of human insulin-like growth factor 1 (IGF-1): an 83-amino-acid version with an N-terminal extension and an arginine substitution at position 3 that greatly lowers its binding to IGF-binding proteins, giving it a much longer active half-life than native IGF-1. It activates the IGF-1 receptor and downstream PI3K/Akt/mTOR signaling that drives protein synthesis and cell growth. It is not approved for human therapeutic use; it is sold as a research reagent and used in laboratory cell culture, and human data on the marketed muscle-building and fat-loss claims are essentially absent. Because it is a systemic growth factor, theoretical risks include effects on blood glucose and concerns about stimulating growth of existing abnormal cells.
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Limited human data
Ipamorelin
Growth & Muscle · GHRP (growth-hormone-releasing peptide)
Ipamorelin is a selective growth hormone secretagogue that stimulates GH release by activating the ghrelin receptor (GHS-R1a). It is often favored over older GHRPs because clinical research (published in the European Journal of Endocrinology) found it produces dose-dependent GH release with little or no effect on ACTH and cortisol, giving it a comparatively clean side-effect profile among GHRPs. It is frequently stacked with CJC-1295 for a synergistic GH pulse, although controlled human outcome data specifically on the combination remains limited. It is not FDA-approved for human use and is prohibited in sport.
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Early human
Kisspeptin-10
Hormonal & Sexual · KP-10
Kisspeptin-10 is the 10-amino-acid C-terminal fragment of kisspeptin, a KISS1-gene-derived neuropeptide that activates the kisspeptin receptor (KISS1R, formerly GPR54) on GnRH neurons. By stimulating GnRH release, it triggers downstream secretion of luteinizing hormone (LH) and follicle-stimulating hormone (FSH), making it a key upstream regulator of the reproductive axis. Kisspeptin is an active area of human research — controlled studies (mostly using kisspeptin-54, with kisspeptin-10 used in some protocols) have probed its effects on reproductive hormones, fertility-related signaling, and, more recently, sexual/brain responses in people with low sexual desire. No kisspeptin product is FDA-approved, and most human work is early-phase or investigational. Marketed claims beyond these research contexts should be treated as unproven.
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Preclinical
KPV
Recovery & Immune · Lys-Pro-Val
KPV is a three-amino-acid peptide (lysine-proline-valine) that is the C-terminal fragment of alpha-melanocyte-stimulating hormone (alpha-MSH). It retains much of the parent hormone's anti-inflammatory activity but, lacking the melanocortin core sequence, does not drive skin pigmentation. In laboratory work it inhibits NF-kB and MAP-kinase inflammatory signaling at low concentrations and is taken into intestinal cells via the PepT1 di/tripeptide transporter, which is up-regulated in inflamed gut tissue — a mechanism that has made it attractive as a potential oral gut anti-inflammatory. Critically, the efficacy evidence is essentially all preclinical: orally delivered KPV reduces the severity of chemically induced (DSS and TNBS) colitis in mice, but there are no published controlled human clinical efficacy trials. It is not FDA-approved for any indication, and human benefit should be considered unproven.
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FDA-approved
Liraglutide
Metabolic & Weight · Victoza
Liraglutide is a once-daily injectable GLP-1 receptor agonist that mimics the incretin hormone GLP-1 to enhance glucose-dependent insulin secretion, slow gastric emptying, and reduce appetite. It is one of the better-evidenced peptides on the market: it is FDA-approved and supported by large Phase 3 trials, sold as Victoza for type 2 diabetes and as Saxenda for chronic weight management. Approval is indication-specific, and as with any approved drug, off-label use is not an endorsement. It is a true peptide analog of human GLP-1.
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Limited human data
LL-37
Recovery & Immune · Cathelicidin antimicrobial peptide
LL-37 is the only human cathelicidin antimicrobial peptide, produced naturally by skin, immune cells and mucosal surfaces as part of innate defense. It has broad-spectrum antimicrobial and anti-biofilm activity and also signals to host cells in ways linked to inflammation, angiogenesis and wound healing. It is more clinically advanced than most research peptides — multiple human trials exist — but the results are mixed and cut both ways. A small Phase I/IIa study in chronic venous leg ulcers reported reduced ulcer area with topical LL-37, but the larger HEAL Phase IIb trial (148 patients) found NO significant healing benefit over placebo. A 3-patient Phase 1 study injected LL-37 into melanoma lesions, and separate research has raised the concern that LL-37 may actually promote tumor invasion in some contexts. It is not FDA-approved for any indication, and the most rigorous wound-healing trial was negative.
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Limited human data
Melanotan-1
Hormonal & Sexual · Melanotan I
Melanotan-1 is a synthetic analogue of alpha-melanocyte-stimulating hormone (alpha-MSH) that stimulates melanocortin-1 receptors (MC1R) to increase eumelanin production in the skin. It is chemically the same molecule as afamelanotide — which IS FDA-approved as the regulated drug Scenesse (2019) for a narrow medical indication (erythropoietic protoporphyria), delivered as a physician-administered implant. Critically, the 'Melanotan-1' sold online as an injectable research chemical for cosmetic tanning is NOT FDA-approved and is not the approved product; it is sold as an unlicensed research chemical and multiple health agencies have warned against it. So the molecule has real Phase 3 human data in its approved medical form, but the marketed cosmetic-tanning use is unapproved and essentially unstudied for safety. Compared with Melanotan-2 it is more MC1R-preferring and generally reported to cause fewer melanocortin side effects (less nausea, less libido effect). Any non-medical 'tanning' use should be treated as unproven and unapproved — see the separate afamelanotide entry for the approved drug.
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Early human
Melanotan-2
Hormonal & Sexual · Melanotan II
Melanotan-2 is a synthetic, non-selective melanocortin receptor agonist developed as a successor to Melanotan-1, acting on MC1R (driving tanning), MC4R (linked to appetite suppression and sexual arousal), and other melanocortin receptors. It is marketed online as an injectable for tanning and sometimes libido, but it is NOT FDA-approved for any use and is sold as an unlicensed research chemical. Its broader receptor activity means more pronounced melanocortin side effects than Melanotan-1, and it carries notable documented safety signals. Health agencies in multiple countries have warned against it. Human efficacy and long-term safety for cosmetic use are not established, and any claimed benefits should be treated as unproven.
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Preclinical
MGF (Mechano Growth Factor)
Growth & Muscle · Mechano Growth Factor
MGF (mechano growth factor) is a splice variant of the IGF-1 gene — known as IGF-1Ec in humans — that muscle produces locally in response to mechanical loading and damage, and it is hypothesized to activate satellite (muscle stem) cells to support repair and growth. Synthetic 'MGF' and 'PEG-MGF' products on the market correspond to its unique E-peptide region. It is not FDA-approved for any indication, and the evidence base is overwhelmingly preclinical: cell-culture and animal studies on satellite-cell activation, with no adequate controlled human trials demonstrating that injected MGF builds muscle in people. Marketed claims about hypertrophy and recovery should be treated as unproven.
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Limited human data
MK-677 (Ibutamoren)
Growth & Muscle · Ibutamoren
MK-677 (ibutamoren) is NOT a peptide — it is an orally active, non-peptide small molecule that mimics the hormone ghrelin at the GHS-R1a receptor and acts as a growth hormone secretagogue, producing sustained increases in growth hormone and IGF-1. It is not FDA-approved for any indication; despite reaching clinical trials (including for conditions such as frailty and growth hormone deficiency), it was never approved and development for general use was not completed. Human studies confirm it reliably raises IGF-1 and can increase lean body mass, but it has also been linked to increased appetite, fluid retention, and reduced insulin sensitivity / higher blood glucose. Marketed claims about muscle building, anti-aging, and sleep should be read against the lack of approval and the unresolved safety questions.
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Early human
MOTS-c
Metabolic & Weight · mitochondrial ORF of the 12S rRNA type-c
MOTS-c is a 16-amino-acid peptide encoded within mitochondrial DNA (the 12S rRNA region), making it unusual among signaling peptides. In preclinical models it activates AMPK and influences glucose handling, insulin sensitivity, and fat metabolism, and because exercise sharply raises endogenous MOTS-c it is often marketed as an 'exercise mimetic.' The human evidence is early and inconsistent: most data are from cells and mice, and observational human findings on circulating MOTS-c and metabolic health are mixed and context-dependent. It is not FDA-approved, and claims of fat loss, performance, or longevity benefit in humans are unproven. It is a true peptide.
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FDA-approved
Oxytocin
Hormonal & Sexual · Pitocin
Oxytocin is a nine-amino-acid neuropeptide hormone produced in the hypothalamus and released from the posterior pituitary, acting on oxytocin receptors to drive uterine contraction and milk let-down, and — in the brain — to modulate social, bonding, and stress-related behaviors. The injectable form (Pitocin) is FDA-approved, but for a specific obstetric purpose: inducing or augmenting labor and controlling postpartum bleeding. Crucially, this approval is indication-specific: the popular intranasal oxytocin marketed for 'bonding,' trust, anxiety, or social connection is NOT FDA-approved, and human studies of intranasal oxytocin for those psychological/social effects are mixed and often fail to replicate. So while oxytocin itself is a well-characterized approved drug, the everyday 'love hormone' use cases are largely unproven.
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FDA-approved
PT-141 (Bremelanotide)
Hormonal & Sexual · Bremelanotide
PT-141 (bremelanotide) is a melanocortin receptor agonist that acts on central nervous system pathways involved in sexual desire and arousal — a different mechanism from blood-flow drugs like sildenafil. It is FDA-approved under the brand name Vyleesi (approved 2019) for hypoactive sexual desire disorder (HSDD) in premenopausal women, with a labeled dose of 1.75 mg subcutaneously at least 45 minutes before anticipated activity (no more than one dose per 24 hours and no more than 8 doses per month). It is also used off-label and compounded for other populations. A transient increase in blood pressure (and decrease in heart rate) is a documented effect to monitor.
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Limited human data
Retatrutide
Metabolic & Weight · LY3437943
Retatrutide is an investigational once-weekly injectable peptide that activates three receptors at once — GIP, GLP-1, and glucagon — a step beyond the dual GLP-1/GIP mechanism of tirzepatide. In a published Phase 2 obesity trial it produced large average weight reductions (up to roughly 24% at 48 weeks at the highest dose), and a Phase 2a substudy showed substantial reductions in liver fat. The human evidence is genuinely promising but still mid-stage: as of 2026 the pivotal Phase 3 program (TRIUMPH) is ongoing and the drug is NOT FDA-approved for any indication. Developed by Eli Lilly. Treat it as an experimental agent whose long-term efficacy and safety are not yet established.
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Limited human data
Selank
Cognitive & Longevity · TP-7
Selank is a synthetic heptapeptide derived from the immune-modulating tetrapeptide tuftsin, developed in Russia as a peptide anxiolytic. It is proposed to influence GABAergic and monoaminergic signaling, enkephalin metabolism, and BDNF expression, with reports of anti-anxiety effects that lack the sedation or dependence associated with benzodiazepines. Small Russian clinical trials in generalized anxiety disorder and neurasthenia have reported benefit, but the studies are limited in size and have not been independently replicated at scale. It is approved in Russia but is NOT FDA-approved, and human evidence for its marketed uses remains limited.
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FDA-approved
Semaglutide
Metabolic & Weight · Ozempic
Semaglutide is a glucagon-like peptide-1 (GLP-1) receptor agonist that mimics a gut hormone the body releases after eating. It slows gastric emptying, increases satiety, and enhances glucose-dependent insulin secretion, which together tend to reduce appetite and food intake. It is one of the best-studied compounds in this dataset, with large Phase 3 RCTs supporting its FDA-approved indications. A documented consideration during GLP-1 therapy is loss of lean (muscle) mass alongside fat mass, which is why adequate protein intake and resistance training are commonly recommended alongside use. This is educational information, not a recommendation to use semaglutide; it is a prescription medication that must be prescribed and supervised by a licensed clinician.
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Limited human data
Semax
Cognitive & Longevity · ACTH(4-10) analog
Semax is a synthetic heptapeptide based on a fragment of adrenocorticotropic hormone (ACTH 4-10), modified with a C-terminal Pro-Gly-Pro to extend its half-life. It is thought to act largely by upregulating BDNF and modulating monoaminergic signaling, without the hormonal (cortisol-releasing) activity of full ACTH. It was developed in Russia and is approved there for ischemic stroke and cognitive indications, but it is NOT FDA-approved in the US. Most of the supporting human data comes from Russian trials that have not been widely replicated by independent Western groups, so claims about cognitive enhancement in healthy people should be treated as preliminary and unproven.
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Limited human data
Sermorelin
Growth & Muscle · Sermorelin acetate
Sermorelin is a GHRH analog corresponding to the first 29 amino acids of natural GHRH. It stimulates the pituitary to release GH in a pulsatile, more physiologic pattern. It was previously FDA-approved (as Geref, approved 1990) for diagnostic and pediatric GH-related use, but the branded product was discontinued for commercial (not safety) reasons. It is now one of the more legally straightforward peptides in the U.S. compounding market: it is available via licensed compounding pharmacies with a prescription and is not on the FDA restricted compounding list. It is, however, prohibited in competitive sport. Educational information only — use requires a prescription and clinician supervision.
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Limited human data
Survodutide
Metabolic & Weight · BI 456906
Survodutide is an investigational once-weekly peptide that activates both the glucagon receptor and the GLP-1 receptor; the glucagon component is intended to raise energy expenditure and act directly on the liver, while GLP-1 activity reduces appetite and supports glycemic control. In a published Phase 2 trial in metabolic dysfunction-associated steatohepatitis (MASH), it significantly improved liver histology versus placebo, and a separate Phase 2 obesity trial showed clinically meaningful weight loss. The evidence is encouraging but mid-stage: as of 2026 it is in Phase 3 development (for both MASH and obesity) and is NOT FDA-approved. Developed by Boehringer Ingelheim (with Zealand Pharma). It is a true peptide.
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Early human
TB-500
Recovery & Immune · Thymosin Beta-4 fragment
TB-500 is a synthetic peptide associated with the actin-binding protein Thymosin Beta-4. In animal and cell studies it has been linked to cell migration, angiogenesis, and tissue repair, and it is marketed for wound healing and muscle/tendon recovery. As with BPC-157, robust human efficacy data is lacking — there are no completed large, controlled human trials supporting the marketed recovery claims. It is frequently stacked with BPC-157 in 'recovery' protocols, but that combination has not been validated in controlled human research. Claims should be treated as preliminary.
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FDA-approved
Tesamorelin
Growth & Muscle · Egrifta
Tesamorelin is a synthetic analog of the 44-amino-acid hypothalamic hormone GHRH, stabilized against enzymatic breakdown, that binds the GHRH receptor and stimulates the pituitary to release the body's own growth hormone. It is FDA-approved (since 2010, marketed as Egrifta) for one narrow indication: reducing excess visceral abdominal fat in people with HIV-associated lipodystrophy, where Phase 3 trials showed a roughly 15-18% reduction in visceral fat versus placebo. That approval does not extend to general fat loss, anti-aging, bodybuilding, or cognition, where evidence is far weaker or absent. As a GHRH analog it raises IGF-1, so people with active cancer or certain other conditions are typically excluded.
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Limited human data
Tesofensine
Metabolic & Weight · NS2330
Tesofensine is a small molecule, not a peptide — it has no amino-acid sequence and works centrally by inhibiting the reuptake of three neurotransmitters (dopamine, norepinephrine, and serotonin), which reduces appetite. It was originally developed for Parkinson's and Alzheimer's disease, where incidental weight loss redirected it toward obesity. A Phase 2 trial (TIPO-1) reported roughly 10% average body-weight loss over 24 weeks, but development has been limited by a cardiovascular safety signal (increases in blood pressure and heart rate). As of 2026 it is NOT FDA-approved in the US (it is approved in Mexico for obesity). Human efficacy beyond Phase 2 is not established in pivotal US trials.
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Early human
Thymalin
Recovery & Immune · Thymalinum
Thymalin is a polypeptide complex extracted from the thymus gland of young calves, developed in the USSR in the 1970s and used in Russia since the 1980s as an immune modulator. It is not a single defined peptide but a mixture of short peptides marketed as a 'bioregulator' that restores T-lymphocyte differentiation and corrects age-related immune decline. Its most striking claim comes from a long-term study by the St. Petersburg (Khavinson/Morozov) group, in which elderly patients given thymalin (alone or with the pineal peptide Epithalamin) over 6-8 years showed large reductions in mortality. These results, however, have not been replicated in independent Western randomized trials, originate almost entirely from a single research school, and are structured in ways outside-reviewers find difficult to audit by modern regulatory standards. As a calf-tissue-derived mixture lacking large independent trials, every benefit claim should be read with caution. It is not FDA-approved.
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Limited human data
Thymosin Alpha-1
Recovery & Immune · Thymalfasin
Thymosin alpha-1 is a 28-amino-acid peptide originally isolated from thymic tissue that modulates the immune system — promoting maturation and function of T-cells, influencing dendritic cells and Toll-like-receptor signaling, and broadly acting as an immune 'tuner' rather than a simple stimulant. It is among the better-studied compounds here, with substantial international clinical use: marketed as Zadaxin (thymalfasin), it is approved in 35-plus countries (including China and Italy) primarily for chronic hepatitis B and as an immune-enhancing adjunct, and it has been studied in sepsis, cancer immunotherapy and respiratory infection. The crucial US nuance: despite decades of use abroad, thymosin alpha-1 is NOT FDA-approved in the United States — the manufacturer reportedly judged US registration trials too costly given the market — so in the US it is not an approved drug. Human evidence for many of its popularly marketed 'immune optimization' and longevity uses remains incomplete.
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Early human
Thymulin
Recovery & Immune · Facteur Thymique Serique
Thymulin (originally called Facteur Thymique Serique, FTS) is a nonapeptide hormone produced by thymic epithelial cells whose biological activity depends on being bound to zinc in a one-to-one ratio. In its zinc-bound form it induces T-cell differentiation and enhances functions of several T-cell subsets, and its plasma level — high early in life — declines to nearly undetectable by roughly the fifth decade, paralleling thymic involution. Most of the human data is descriptive: studies have measured reduced thymulin activity in malnutrition, zinc deficiency, anorexia nervosa and aging, and have explored the zinc-thymulin relationship. What is largely missing is controlled human efficacy trials showing that supplementing thymulin (or analogs) improves clinical outcomes, so the popularly marketed immune-restoration claims rest mainly on mechanism, animal work and observational human associations. It is not FDA-approved for any indication.
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FDA-approved
Tirzepatide
Metabolic & Weight · Mounjaro
Tirzepatide activates both the GLP-1 and the GIP receptors. In the head-to-head SURMOUNT-5 Phase 3b RCT (published in the New England Journal of Medicine, 2025), tirzepatide produced greater average weight loss than semaglutide over 72 weeks (approximately 20.2% vs 13.7% reduction in body weight). The dual mechanism is hypothesized to influence fat oxidation, but lean-mass loss can still occur with rapid weight reduction, so protein intake and resistance training are commonly emphasized. Like semaglutide, this is a prescription medication that must be prescribed and supervised by a licensed clinician; the information here is educational only.
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Limited human data
VIP (Vasoactive Intestinal Peptide)
Recovery & Immune · Vasoactive Intestinal Polypeptide
Vasoactive Intestinal Peptide (VIP) is a naturally occurring 28-amino-acid neuropeptide with vasodilatory, anti-inflammatory and immune-modulating activity; it acts at VPAC1/VPAC2 receptors and, in the lung, protects alveolar type II cells. The synthetic form, aviptadil (brand name Zyesami / RLF-100), has been studied clinically — most prominently inhaled VIP in sarcoidosis (a 20-patient study showed reduced TNF-alpha production and increased regulatory T-cells in lung lavage) and in pulmonary arterial hypertension, plus a high-profile program in severe COVID-19 respiratory failure. That COVID program ultimately failed: the FDA twice declined Emergency Use Authorization (2021 and 2022) and the NIH ACTIV-3b trial's aviptadil arm was stopped after it did not beat placebo at interim analysis. Aviptadil holds FDA Orphan Drug and Fast Track designations for ARDS but is NOT FDA-approved for any indication.
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The peptide reference

5-Amino-1MQ

ACE-031

Adipotide

Afamelanotide

AOD-9604

ARA-290 (Cibinetide)

BPC-157

Cagrilintide

Cerebrolysin

CJC-1295

Dihexa

DSIP (Delta Sleep-Inducing Peptide)

Dulaglutide

Elamipretide (SS-31)

Epitalon

Follistatin

FOXO4-DRI

GHK-Cu

GHRP-2

GHRP-6

Gonadorelin (GnRH)

Hexarelin

Humanin

IGF-1 LR3

Ipamorelin

Kisspeptin-10

KPV

Liraglutide

LL-37

Melanotan-1

Melanotan-2

MGF (Mechano Growth Factor)

MK-677 (Ibutamoren)

MOTS-c

Oxytocin

PT-141 (Bremelanotide)

Retatrutide

Selank

Semaglutide

Semax

Sermorelin

Survodutide

TB-500

Tesamorelin

Tesofensine

Thymalin

Thymosin Alpha-1

Thymulin

Tirzepatide

VIP (Vasoactive Intestinal Peptide)