Peptides are short chains of amino acids (the same fundamental building blocks that make up proteins) but they function in the body in a unique and highly targeted way. Rather than acting as structural components like many larger proteins, peptides typically serve as biological signaling molecules, helping cells communicate and coordinate complex physiological processes.
They play essential roles in regulating metabolism, hormone release, immune responses, inflammation, tissue repair, appetite, sleep, and many other functions. Examples of naturally occurring peptides include insulin, glucagon, growth hormone–releasing peptides, and numerous immune signaling molecules.
Because of their size and structure, peptides occupy a distinct space between traditional small-molecule drugs and larger biologic therapies. This gives them several unique characteristics:
High specificity
Peptides often bind very precisely to receptors, allowing them to influence particular biological pathways with relatively targeted effects.
Powerful physiological impact
Even small changes in peptide signaling can lead to meaningful changes in metabolism, recovery, or hormonal rhythms.
Shorter biological half-lives
Many peptides are rapidly broken down in the body, which can reduce long-term accumulation but may require careful dosing strategies.
Growing therapeutic interest
Advances in biotechnology have made it easier to design and synthesize peptides, leading to increasing exploration of their potential uses in medicine and longevity science.
For these reasons, peptides are often discussed as a category of their own. They represent a class of bioactive molecules that can directly influence regulatory systems within the body.
However, this biological potency also means that peptides are not risk-free.
Peptides are not risk-free. Before considering their use, it is essential to carefully weigh potential benefits against possible risks: side effects, unknown long-term outcomes, dosing challenges, and product purity. Decisions should be based on credible evidence and ideally made in consultation with a qualified healthcare professional.
The tables below summarize commonly discussed peptides, their mechanisms of action, and the current state of evidence. Expand a peptide for its mechanism, evidence, risks and contraindications.
Evidence grades: A Multiple large RCTs · B Strong RCT; optimization off-label · C Small or surrogate-endpoint human trials · D Limited human evidence · E No persuasive human evidence; primarily preclinical
Regulatory note: WADA status reflects the 2026 Prohibited List. For educational purposes only. Always consult a licensed physician.
Incretin & Metabolic Peptides
| Peptide (brand names) | Evidence | Indication | Regulatory status |
|---|---|---|---|
|
Semaglutide Wegovy, Ozempic, Rybelsus |
A | Obesity (BMI ≥30 or ≥27 + comorbidity); T2DM; CV risk reduction | FDA-approved 2021 (obesity). EMA Jan 2022. Rx only. WADA: Not prohibited |
|
Tirzepatide Zepbound, Mounjaro |
A | Obesity; T2DM; obstructive sleep apnea in adults with obesity | FDA-approved 2022 (T2DM), 2023 (obesity), 2024 (OSA). Rx only. WADA: Not prohibited |
|
Liraglutide Saxenda, Victoza |
A | Obesity (BMI ≥30 or ≥27 + comorbidity); T2DM | FDA-approved (Rx). Saxenda label current 2025. WADA: Not prohibited |
|
Exenatide Byetta, Bydureon ER |
B | T2DM (not primarily indicated for obesity/wellness) | FDA-approved (Rx). Byetta label current 2025. WADA: Not prohibited |
|
Pramlintide Symlin |
B | T2DM and T1DM insulin adjunct; studied for obesity as lifestyle adjunct | FDA-approved (Rx) for diabetes adjunct. Obesity use off-label. WADA: Not prohibited |
Semaglutide — Wegovy, Ozempic, Rybelsus · Evidence A
Class & mechanism of action: GLP-1 receptor agonist (31-aa). Selective GLP-1R agonist; reduces appetite; slows gastric emptying; glucose-dependent insulin effects; albumin-binding fatty acid chain extends t½ ~168h.
Key benefits (human evidence): STEP 1 (NEJM 2021): 14.9% weight loss vs 2.4% placebo. SELECT (NEJM 2023, n=17,604): 20% ↓ MACE. HbA1c reduction 1.5–2.0%.
Adverse events & risks: Nausea (40–44%), vomiting (24%), diarrhea (30%), constipation. Boxed warning: thyroid C-cell tumors (rodent). Pancreatitis, gallbladder disease, renal injury.
Contraindications: MEN2, medullary thyroid carcinoma, pregnancy. Caution: pancreatitis history, gastroparesis.
Regulatory status: FDA-approved 2021 (obesity). EMA Jan 2022. Rx only. WADA: Not prohibited
Tirzepatide — Zepbound, Mounjaro · Evidence A
Class & mechanism of action: GIP/GLP-1 dual agonist (39-aa). Dual GIPR + GLP-1R agonism; appetite/weight reduction; gastric emptying effects; t½ ~5 days.
Key benefits (human evidence): SURMOUNT-1 (NEJM 2022): 20.9% weight loss at 15 mg vs 3.1% placebo. SURPASS-2: superior HbA1c vs semaglutide 1 mg.
Adverse events & risks: Nausea (30%), diarrhea (23%), vomiting (18%). Boxed warning: thyroid C-cell tumors (rodent). Reduces oral contraceptive exposure early in treatment.
Contraindications: MEN2, medullary thyroid carcinoma, pregnancy. Caution: severe GI motility disorders.
Regulatory status: FDA-approved 2022 (T2DM), 2023 (obesity), 2024 (OSA). Rx only. WADA: Not prohibited
Liraglutide — Saxenda, Victoza · Evidence A
Class & mechanism of action: GLP-1 receptor agonist (31-aa). GLP-1R agonist; appetite reduction; delayed gastric emptying. Daily dosing required.
Key benefits (human evidence): SCALE (NEJM 2015, n=3,731): 8.4% weight loss vs 2.8% placebo at 56 weeks.
Adverse events & risks: GI AEs (nausea, diarrhea, vomiting). Boxed warning: thyroid C-cell tumors (rodent). Pancreatitis, gallbladder warnings.
Contraindications: MEN2, medullary thyroid carcinoma, pregnancy.
Regulatory status: FDA-approved (Rx). Saxenda label current 2025. WADA: Not prohibited
Exenatide — Byetta, Bydureon ER · Evidence B
Class & mechanism of action: GLP-1 receptor agonist (39-aa). GLP-1R agonist; glucose-dependent insulin secretion; slows gastric emptying.
Key benefits (human evidence): Multiple T2DM RCTs for glycemic control. Less weight loss than semaglutide/tirzepatide.
Adverse events & risks: GI AEs; hypoglycemia risk with insulin/sulfonylureas; renal cautions; injection site nodules (ER).
Contraindications: eGFR <45 mL/min/1.73m² (Byetta); severe GI disease; MEN2/medullary thyroid CA.
Regulatory status: FDA-approved (Rx). Byetta label current 2025. WADA: Not prohibited
Pramlintide — Symlin · Evidence B
Class & mechanism of action: Amylin analog (37-aa). Slows gastric emptying; suppresses postprandial glucagon; increases satiety.
Key benefits (human evidence): 12-month obesity lifestyle-adjunct RCT: weight loss support demonstrated (Smith 2008).
Adverse events & risks: Nausea (most common); hypoglycemia risk when combined with insulin at initiation.
Contraindications: Hypoglycemia unawareness; gastroparesis; must adjust insulin dose at initiation.
Regulatory status: FDA-approved (Rx) for diabetes adjunct. Obesity use off-label. WADA: Not prohibited
Growth Hormone (GH) Axis Peptides
| Peptide (brand names) | Evidence | Indication | Regulatory status |
|---|---|---|---|
|
Tesamorelin Egrifta WR |
B | HIV lipodystrophy (excess abdominal fat). NOT indicated for weight loss management | FDA-approved (Rx) for HIV lipodystrophy ONLY. WADA: Prohibited (S2) |
|
Sermorelin Geref (discontinued) |
C | Historically: pediatric GH deficiency. Now compounded off-label for anti-aging / body composition | US product withdrawn. Compounded only. Not FDA-approved. WADA: Prohibited (S2) |
|
CJC-1295 CJC-1295 w/ DAC; MOD GRF 1-29 |
C | Investigational: GH/IGF-1 axis enhancement, body composition, anti-aging | Not FDA-approved. Higher-risk bulk substance for compounding. WADA: Prohibited (S2) |
|
Ipamorelin Ipamorelin |
C | Investigational: GH secretagogue. Phase II RCT for postoperative ileus showed NO significant benefit | Not FDA-approved. Bulk substance with potential significant safety risk. WADA: Prohibited (S2) |
|
GHRP-2 Pralmorelin (Japan: diagnostic) |
C | Clinical GH stimulation/diagnostic use (Japan approved). Wellness use not clinically validated | Not FDA-approved. Japan approval for diagnostic use only. WADA: Prohibited (S2) |
|
GHRP-6 GHRP-6 |
D | Investigational: GH secretagogue. No robust wellness outcomes RCT base | Not FDA-approved. FDA compounding risk flagged. WADA: Prohibited (S2) |
Tesamorelin — Egrifta WR · Evidence B
Class & mechanism of action: GHRH analog (44-aa). Stimulates GHRH receptors → ↑ endogenous GH → ↑ IGF-1; reduces visceral adipose tissue via GH-mediated lipolysis.
Key benefits (human evidence): RCTs in HIV lipodystrophy: significant VAT reduction vs placebo.
Adverse events & risks: ↑IGF-1 (monitor); fluid retention; arthralgias; glucose perturbation. Long-term CV safety not established.
Contraindications: Active malignancy; disruption of HPA axis; pregnancy.
Regulatory status: FDA-approved (Rx) for HIV lipodystrophy ONLY. WADA: Prohibited (S2)
Sermorelin — Geref (discontinued) · Evidence C
Class & mechanism of action: GHRH analog (29-aa). GHRH(1–29) peptide; binds GHRH receptor → pulsatile GH release.
Key benefits (human evidence): Historical pediatric GH deficiency data only. No modern adult optimization RCTs.
Adverse events & risks: Limited modern adult safety data. GH-related effects theoretical. Compounded product quality concerns.
Contraindications: Active malignancy; pregnancy (unknown); compounded quality risks.
Regulatory status: US product withdrawn. Compounded only. Not FDA-approved. WADA: Prohibited (S2)
CJC-1295 — CJC-1295 w/ DAC; MOD GRF 1-29 · Evidence C
Class & mechanism of action: GHRH analog with DAC modification. Drug Affinity Complex extends t½ to 6–8 days. Stimulates pulsatile GH release.
Key benefits (human evidence): Phase I/II (Walker 2006): dose-dependent IGF-1 elevation in healthy adults. Biomarker outcome only.
Adverse events & risks: Water retention, tingling, lethargy, somnolence. Theoretical: sustained IGF-1 elevation, insulin resistance, neoplasia risk.
Contraindications: Active malignancy; diabetic retinopathy; pregnancy; prior pituitary adenoma; competitive sport.
Regulatory status: Not FDA-approved. Higher-risk bulk substance for compounding. WADA: Prohibited (S2)
Ipamorelin — Ipamorelin · Evidence C
Class & mechanism of action: GHSR agonist / ghrelin mimetic. Selective ghrelin/GHSR1a agonist. Stimulates pulsatile GH release without significant cortisol/prolactin elevation.
Key benefits (human evidence): Postoperative ileus Phase II RCT (2014): NO significant benefit on primary endpoint.
Adverse events & risks: FDA flags: limited human exposure/safety signals, impurity/characterization issues.
Contraindications: Active malignancy; pregnancy (unknown); competitive sport.
Regulatory status: Not FDA-approved. Bulk substance with potential significant safety risk. WADA: Prohibited (S2)
GHRP-2 — Pralmorelin (Japan: diagnostic) · Evidence C
Class & mechanism of action: GH secretagogue. Ghrelin/GHS-related peptide; GH secretagogue via GHSR.
Key benefits (human evidence): Clinical use as GH stimulation/diagnostic agent in Japan. Wellness claims not clinically validated.
Adverse events & risks: FDA flags compounding risks; limited wellness outcome evidence.
Contraindications: Active malignancy; pregnancy; competitive sport.
Regulatory status: Not FDA-approved. Japan approval for diagnostic use only. WADA: Prohibited (S2)
GHRP-6 — GHRP-6 · Evidence D
Class & mechanism of action: GH secretagogue. Also stimulates cortisol and prolactin — less selective than ipamorelin. Significant appetite stimulation.
Key benefits (human evidence): No robust wellness outcomes RCT base. Biomarker studies only.
Adverse events & risks: FDA flags compounding risks; endocrine perturbations (cortisol, prolactin) plausible.
Contraindications: Active malignancy; pregnancy; competitive sport.
Regulatory status: Not FDA-approved. FDA compounding risk flagged. WADA: Prohibited (S2)
Melanocortin Peptides
| Peptide (brand names) | Evidence | Indication | Regulatory status |
|---|---|---|---|
|
Afamelanotide Scenesse, Melanotan I |
B | Erythropoietic protoporphyria (EPP). NOT a tanning drug | FDA-approved for EPP indication only (2019). WADA: Not prohibited |
|
Melanotan II MT-II |
E | Marketed for tanning/libido. NOT approved anywhere. Serious adverse event case reports | Not FDA-approved. FDA flags significant safety concerns. WADA: Not prohibited |
|
PT-141 (Bremelanotide) Vyleesi |
A | HSDD in premenopausal women. NOT for postmenopausal women, men, or performance enhancement | FDA-approved June 2019 (NDA 210557). Premenopausal HSDD only. WADA: Not prohibited |
Afamelanotide — Scenesse, Melanotan I · Evidence B
Class & mechanism of action: MC1R agonist (13-aa). Predominantly MC1R agonism; increases eumelanin synthesis → photoprotection.
Key benefits (human evidence): Pivotal EPP RCTs (Langendonk, NEJM 2015): significant improvement in pain-free sunlight exposure vs placebo.
Adverse events & risks: Hyperpigmentation; nevus darkening (skin monitoring required); nausea, fatigue; implant site reactions.
Contraindications: Not for cosmetic tanning. Skin lesion monitoring required. Caution in pregnancy.
Regulatory status: FDA-approved for EPP indication only (2019). WADA: Not prohibited
Melanotan II — MT-II · Evidence E
Class & mechanism of action: Nonselective MC agonist (cyclic heptapeptide). Nonselective melanocortin receptor agonism (MC1R, MC3R, MC4R, MC5R).
Key benefits (human evidence): Very small Phase I study (3 volunteers) only. No validated wellness benefit.
Adverse events & risks: SERIOUS: case reports of priapism, systemic toxidrome, rhabdomyolysis, acute renal dysfunction.
Contraindications: Should not be used — no approved indication. Significant serious AE case report profile.
Regulatory status: Not FDA-approved. FDA flags significant safety concerns. WADA: Not prohibited
PT-141 (Bremelanotide) — Vyleesi · Evidence A
Class & mechanism of action: MC receptor agonist (cyclic heptapeptide). MC4R agonism in hypothalamus increases sexual desire independent of sex hormone pathways.
Key benefits (human evidence): RECONNECT Phase III (n=1,267): significant ↑ satisfying sexual events and ↓ distress vs placebo.
Adverse events & risks: Nausea (40%), flushing (20%), injection site bruising (11%), headache. Transient BP increase.
Contraindications: Uncontrolled hypertension; cardiovascular disease; concomitant naltrexone; pregnancy.
Regulatory status: FDA-approved June 2019 (NDA 210557). Premenopausal HSDD only. WADA: Not prohibited
Neurobehavioral Peptides
| Peptide (brand names) | Evidence | Indication | Regulatory status |
|---|---|---|---|
|
Oxytocin Pitocin, intranasal (off-label) |
C | FDA-approved: obstetric indications. Off-label/research: autism social outcomes, anxiety, bonding | FDA-approved for obstetric indications only. Intranasal wellness is off-label/research. WADA: Not prohibited |
|
Desmopressin Nocdurna, DDAVP |
B | Nocturia; central diabetes insipidus; nocturnal enuresis. NOT a wellness agent | FDA-approved (Rx). Boxed warning for hyponatremia. WADA: Not prohibited |
|
DSIP Emideltide, Delta Sleep-Inducing Peptide |
D | Investigational: sleep induction, insomnia. Evidence weak and limited | Not FDA-approved. Higher-risk compounding bulk substance. WADA: Not prohibited |
|
Selank Selank |
C | Anxiety, cognitive enhancement (Russia/Ukraine approved). Research compound in Western markets | Approved in Russia. NOT approved in US, EU, or UK. WADA: Not prohibited |
|
Semax Semax |
D | Cognitive enhancement, neuroprotection (Russia/Ukraine approved). Not approved in Western markets | Approved in Russia. NOT approved in US, EU, or UK. WADA: Not prohibited |
Oxytocin — Pitocin, intranasal (off-label) · Evidence C
Class & mechanism of action: Nonapeptide hormone. Oxytocin receptor agonist. Complex social, affiliative, and anxiolytic effects via hypothalamic and limbic circuits.
Key benefits (human evidence): Autism/social RCT (Nature 2022): NO overall primary outcome benefit. Meta-analyses: mixed findings.
Adverse events & risks: Context-dependent psychological effects. Off-label intranasal long-term safety gaps.
Contraindications: Wellness intranasal: insufficient long-term safety data.
Regulatory status: FDA-approved for obstetric indications only. Intranasal wellness is off-label/research. WADA: Not prohibited
Desmopressin — Nocdurna, DDAVP · Evidence B
Class & mechanism of action: Vasopressin analog. V2 receptor agonism → antidiuresis. Sodium monitoring mandatory at initiation.
Key benefits (human evidence): Nocturia and DI indications supported by RCT evidence.
Adverse events & risks: BOXED WARNING: hyponatremia (seizures, coma, respiratory arrest, death).
Contraindications: Hyponatremia or risk states; loop diuretics; glucocorticoids; polydipsia; renal impairment; elderly.
Regulatory status: FDA-approved (Rx). Boxed warning for hyponatremia. WADA: Not prohibited
DSIP — Emideltide, Delta Sleep-Inducing Peptide · Evidence D
Class & mechanism of action: Neuropeptide (nonapeptide). Proposed sleep-modulating neuropeptide. Mechanism incompletely characterized in humans.
Key benefits (human evidence): Small double-blind placebo-controlled insomnia study (IV): weak effects. No modern replication.
Adverse events & risks: Sparse modern safety data. No systematic human AE profile.
Contraindications: Unknown. IV requirement limits wellness applicability.
Regulatory status: Not FDA-approved. Higher-risk compounding bulk substance. WADA: Not prohibited
Selank — Selank · Evidence C
Class & mechanism of action: Anxiolytic heptapeptide (tuftsin analogue). Modulates GABA-A receptors, increases BDNF and NGF.
Key benefits (human evidence): Russian trials: anxiolytic non-inferiority to benzodiazepines without tolerance. NOT replicated in Western RCTs.
Adverse events & risks: Well-tolerated in Russian trials. Nasal irritation. FDA flags: major evidence and quality gaps.
Contraindications: Pregnancy (insufficient data); concurrent benzodiazepines; unknown interactions.
Regulatory status: Approved in Russia. NOT approved in US, EU, or UK. WADA: Not prohibited
Semax — Semax · Evidence D
Class & mechanism of action: ACTH analogue neuropeptide (heptapeptide). Synthetic ACTH(4–10) analogue; modulates BDNF, increases NGF.
Key benefits (human evidence): Russian data for stroke rehabilitation and cognitive enhancement. Not replicated in Western RCTs.
Adverse events & risks: Limited Western safety data. FDA flags: major evidence and quality gaps.
Contraindications: Unknown in Western context. Pregnancy unknown.
Regulatory status: Approved in Russia. NOT approved in US, EU, or UK. WADA: Not prohibited
Endocrine Peptides
| Peptide (brand names) | Evidence | Indication | Regulatory status |
|---|---|---|---|
|
Kisspeptin-10 Kp-10 |
C | Investigational: reproductive endocrinology, LH/FSH stimulation, emerging sexual function research | Not FDA-approved. FDA compounding risk flagged. WADA: Not prohibited |
Kisspeptin-10 — Kp-10 · Evidence C
Class & mechanism of action: GnRH axis activator (decapeptide). Stimulates GnRH → ↑ LH/FSH (context-dependent).
Key benefits (human evidence): Human endocrine trials: stimulation of LH pulses in men and women. No wellness outcomes RCTs.
Adverse events & risks: Limited broad safety data for non-reproductive wellness use. Endocrine perturbation theoretical.
Contraindications: Hormone-sensitive malignancy; pregnancy; unknown long-term safety.
Regulatory status: Not FDA-approved. FDA compounding risk flagged. WADA: Not prohibited
Repair & Regenerative Peptides
| Peptide (brand names) | Evidence | Indication | Regulatory status |
|---|---|---|---|
|
BPC-157 Body Protection Compound-157, PL-14736 |
E | Investigational: GI mucosal healing, tendon/ligament repair, wound healing. Human evidence sparse | Not FDA-approved. Bulk substance with potential significant safety risks. WADA: Not prohibited |
|
TB-500 TB-500 (LKKTETQ fragment) |
E | Investigational: tissue repair, wound healing. NOT full-length Thymosin β4 | Not FDA-approved. Bulk substance with potential significant safety risks. WADA: Not prohibited |
|
LL-37 LL-37, Human cathelicidin |
C | Investigational: wound healing (venous leg ulcers), innate immune modulation | Not FDA-approved. FDA compounding risk flagged. WADA: Not prohibited |
BPC-157 — Body Protection Compound-157, PL-14736 · Evidence E
Class & mechanism of action: Cytoprotective pentadecapeptide (15-aa). Activates FAK-paxillin pathway, upregulates VEGFR2, modulates NO system.
Key benefits (human evidence): Primarily preclinical (rodent). No completed Phase II/III RCTs. FDA explicitly cites lack of reliable human exposure data.
Adverse events & risks: No systematic human AE data. FDA flags: product quality concerns, immunogenicity risks.
Contraindications: Unknown safety profile. No established contraindications due to absence of clinical data.
Regulatory status: Not FDA-approved. Bulk substance with potential significant safety risks. WADA: Not prohibited
TB-500 — TB-500 (LKKTETQ fragment) · Evidence E
Class & mechanism of action: Thymosin β4 heptapeptide fragment (7-aa). Claimed repair/angiogenesis effects extrapolated from full-length biology — NOT clinically validated.
Key benefits (human evidence): No reliable published human outcomes evidence for TB-500 (LKKTETQ fragment).
Adverse events & risks: No systematic human AE data. FDA flags: quality/impurity risks, no human exposure data.
Contraindications: Active malignancy (theoretical). Pregnancy (unknown).
Regulatory status: Not FDA-approved. Bulk substance with potential significant safety risks. WADA: Not prohibited
LL-37 — LL-37, Human cathelicidin · Evidence C
Class & mechanism of action: Antimicrobial peptide (37-aa). Innate immune modulation; promotes wound healing via cell migration and angiogenesis.
Key benefits (human evidence): Venous leg ulcer RCT (Lundqvist 2014): improved healing with topical LL-37. Does NOT validate systemic injectable use.
Adverse events & risks: FDA flags: male reproductive toxicity, protumorigenic findings. Injectable use has no validated safety data.
Contraindications: Active malignancy; male reproductive concerns; pregnancy (unknown).
Regulatory status: Not FDA-approved. FDA compounding risk flagged. WADA: Not prohibited
Immune, Longevity & Other Peptides
| Peptide (brand names) | Evidence | Indication | Regulatory status |
|---|---|---|---|
|
Thymosin Alpha-1 Zadaxin, Thymalfasin |
C | Hepatitis B/C, cancer adjunct, immune deficiency (approved China, Italy, 35+ countries). Not FDA-approved | Approved in China, Italy (Zadaxin), 35+ countries. NOT FDA-approved. WADA: Not prohibited |
|
GHK-Cu Copper tripeptide, copper peptide |
D | Cosmetic/dermatologic: skin aging, wound healing (topical). Injectable claims NOT validated | Not FDA-approved as a drug. FDA compounding risk flagged for injectable forms. WADA: Not prohibited |
|
Epithalon Epitalon, Epithalone, AEDG |
E | Investigational: longevity, circadian rhythm restoration, telomere biology. No robust human clinical evidence | Not approved anywhere. Research use only. FDA compounding risk flagged. WADA: Not prohibited |
|
MOTS-c MOTS-c |
E | Investigational: metabolic disease, aging, exercise performance. No human RCTs | Not approved. Research compound. FDA compounding risk flagged. WADA: Not prohibited |
Thymosin Alpha-1 — Zadaxin, Thymalfasin · Evidence C
Class & mechanism of action: Thymic peptide / immune modulator (28-aa). Activates dendritic cells via TLR2/TLR9, promotes Th1 differentiation.
Key benefits (human evidence): HBV RCTs (n>500 aggregate): virologic response improvements. COVID-19 pilot (Liu Y, CID 2020): reduced mortality.
Adverse events & risks: Well-tolerated in >30 years of international use. Injection site reactions, mild fatigue.
Contraindications: Caution: autoimmune disease (Th1 amplification); organ transplant recipients; pregnancy.
Regulatory status: Approved in China, Italy (Zadaxin), 35+ countries. NOT FDA-approved. WADA: Not prohibited
GHK-Cu — Copper tripeptide, copper peptide · Evidence D
Class & mechanism of action: Copper-binding tripeptide (Gly-His-Lys). Modulates collagen synthesis, TGF-β signaling, VEGF.
Key benefits (human evidence): Mostly cosmetic/dermatologic human data via topical use. Injectable wellness claims not validated.
Adverse events & risks: FDA flags compounding risks for injectable use. Copper toxicity theoretical at high systemic doses.
Contraindications: Injectable use: unknown safety profile; Wilson disease; pregnancy.
Regulatory status: Not FDA-approved as a drug. FDA compounding risk flagged for injectable forms. WADA: Not prohibited
Epithalon — Epitalon, Epithalone, AEDG · Evidence E
Class & mechanism of action: Pineal tetrapeptide (Ala-Glu-Asp-Gly). Proposed: telomerase activation, melatonin synthesis restoration.
Key benefits (human evidence): Human anti-aging evidence limited/contested. No placebo-controlled RCTs on ClinicalTrials.gov.
Adverse events & risks: No systematic human safety data. Theoretical: telomerase activation and neoplasia.
Contraindications: Active cancer (theoretical telomerase risk). Pregnancy (unknown).
Regulatory status: Not approved anywhere. Research use only. FDA compounding risk flagged. WADA: Not prohibited
MOTS-c — MOTS-c · Evidence E
Class & mechanism of action: Mitochondrial-derived peptide (12-aa). Activates AMPK and FOXO signaling, enhances insulin sensitivity, promotes fatty acid oxidation.
Key benefits (human evidence): Kim SJ et al. Cell Metab 2015: reduces diet-induced obesity in mice. No Phase I/II human trials completed.
Adverse events & risks: No human safety data. FDA flags limited human exposure data and compounding risks.
Contraindications: Unknown. No clinical data.
Regulatory status: Not approved. Research compound. FDA compounding risk flagged. WADA: Not prohibited
