FAQ
Common Questions, Literature Answers
Questions from the corpus, answered from the published evidence — cited, honest about gaps, and without dosing recommendations.
What does BPC-157 do in the body?
In animal models, BPC-157 appears to accelerate healing in several tissue types — tendons [6], the gut lining [5], and muscle — with the most consistently reported mechanism being stimulation of new blood-vessel growth (angiogenesis) through the VEGFR2 pathway [4]. In one 2025 review, it is described as a cytoprotective peptide whose effects are tied to VEGFR2-Akt-eNOS signaling, growth-hormone-receptor sensitization in tendons, and modulation of neurotransmitter systems [2]. Human data are extremely limited: as of 2025, only three small pilot studies exist, none of them adequately powered to confirm therapeutic effects in people [2].
Is BPC-157 a growth hormone?
No. BPC-157 is a 15-amino-acid gastric peptide, not a growth hormone. It does not directly stimulate pituitary GH secretion. In tendon fibroblast studies it appears to sensitize growth-hormone receptors [2], which is a different mechanism from a growth hormone or a GH secretagogue like CJC-1295. Do not conflate them.
Does BPC-157 work immediately?
The animal studies do not describe an immediate single-dose effect — improved healing in rat tendon and gut models accumulates over days to weeks of the study period [5][6]. A first-in-human IV pilot reported no adverse events but was not an efficacy study, so "how fast" BPC-157 works in people is genuinely unknown [1]. Popular claims about rapid onset are not grounded in controlled human evidence.
Does BPC-157 damage the liver?
No hepatotoxic findings appear in the animal literature, and a 2025 human IV pilot observed no changes in hepatic biomarkers in two adults at up to 20 mg IV [1]. However, the human evidence base is extraordinarily small — two people — so absence of harm in this pilot does not establish liver safety at scale. The compound is not approved, and long-term human safety data do not exist [2].
What is CJC-1295?
CJC-1295 is a synthetic analog of growth-hormone-releasing hormone (GHRH), built on the first 29 residues of human GRF with four stabilizing amino-acid substitutions. The DAC (Drug Affinity Complex) variant adds a chemical moiety that binds to serum albumin, extending its half-life to roughly 5.8–8.1 days in humans [11]. The no-DAC variant (often called Modified GRF 1-29) lacks the albumin-binding component and acts for only minutes to hours. The two are frequently confused in community discussions [8].
What does CJC-1295 do?
CJC-1295 binds the GHRH receptor on anterior-pituitary somatotrophs, stimulating pulsatile growth-hormone release and downstream IGF-1 production. A 2006 human pharmacology study in healthy adults found single doses raised mean GH 2- to 10-fold and IGF-1 1.5- to 3-fold for 6–11 days [11]. A separate study confirmed that pulsatile GH secretion is preserved — not flattened — under continuous GHRH-analog stimulation [12]. It does not directly cause muscle growth; any such effect would be downstream of the GH/IGF-1 axis.
Is CJC-1295 safe?
CJC-1295 was not approved by any regulator, and its DAC development program was discontinued. The FDA's 2024 Pharmacy Compounding Advisory Committee cited immunogenicity and other safety concerns for GH secretagogues including CJC-1295 [8]. Sustained GH/IGF-1 elevation raises mechanism-based concerns: fluid retention, blood-sugar effects, and epidemiological associations between higher IGF-1 and cancer risk. Published human data are limited to early pharmacology studies; no long-term safety trials were completed.
How much CJC-1295 should I take?
This desk does not provide dosing recommendations for any compound, including CJC-1295. Human pharmacology studies used weight-based dosing under clinical supervision [11][12]; those parameters belong in a research protocol, not a general guide. CJC-1295 is not an approved drug, and circulating online "dosing protocols" are not derived from controlled human trials.
What does retatrutide do?
Retatrutide is an investigational once-weekly injectable that simultaneously activates three receptors: GLP-1R, GIPR, and the glucagon receptor [14]. GLP-1 and GIP arms suppress appetite and improve glucose-dependent insulin secretion; the glucagon arm adds energy expenditure and lipid mobilization. In a 48-week Phase 2 obesity trial, participants at the highest dose lost a mean of 24.2% of body weight versus 2.1% with placebo [16]. A separate Phase 2 trial in type 2 diabetes showed HbA1c reduced by 2.02% [17].
How does retatrutide work?
Cryo-EM structural studies resolved retatrutide's simultaneous binding to all three receptors [14]. The compound is roughly 8.9-times more potent at GIPR than native GIP, but weaker than native hormones at GCGR (0.3x) and GLP-1R (0.4x). Its C20 fatty-diacid modification binds serum albumin, extending the half-life to support once-weekly dosing. The combined tri-agonism is what drives the larger weight-loss signal compared to dual- or single-agonist agents in the same drug class [13].
How to reconstitute retatrutide?
Retatrutide is an investigational drug available only through clinical trials as of 2026 — it has no approved formulation or prescribing information. This desk does not provide reconstitution protocols or handling instructions for any unapproved compound. Material sold through gray-market channels as retatrutide cannot be confirmed to contain what is claimed [16].
Is retatrutide FDA approved?
No. Retatrutide (LY3437943) is not approved by the FDA or any regulator as of mid-2026. It remains in Phase 3 clinical trials (the TRIUMPH program) being conducted by Eli Lilly [13]. Any retatrutide obtained outside a registered clinical trial is gray-market material of unverified identity, purity, and sterility.
What does a GHK-Cu peptide do?
GHK-Cu is a copper tripeptide (Gly-His-Lys chelated to a Cu(II) ion) that acts as both a copper chaperone and a signaling molecule. At picomolar-to-nanomolar concentrations it stimulates dermal fibroblasts to synthesize collagen, elastin, and glycosaminoglycans, and rebalances matrix metalloproteinases [21]. Topical clinical trials have shown increased collagen production in 70% of treated subjects versus 50% for vitamin C and 40% for retinoic acid [21]. A 6-month RCT in men with hair loss found statistically significant hair-count increases with a GHK-containing formulation [20].
What is GHK-Cu and how does it work?
GHK-Cu is a Glycyl-L-Histidyl-L-Lysine Copper(II) complex that occurs endogenously in human plasma (declining from ~200 ng/mL at age 20 to ~80 ng/mL at age 60 [21]) and in the alpha-2(I) chain of type I collagen. The copper ion enables lysyl oxidase-mediated cross-linking of collagen and elastin and provides superoxide-dismutase-like antioxidant activity. Gene-expression analysis reports GHK modulates about 31.2% of human genes at a 50%-or-greater change threshold, upregulating tissue-repair, DNA-repair, and antioxidant programs [19].
Is GHK-Cu peptide really anti-aging?
The mechanism-based and cell-study data are genuinely interesting — collagen synthesis, antioxidant activity, broad gene-expression shifts [19][21] — but the human clinical evidence is modest: small topical trials and one 45-person hair RCT [20]. Much of the foundational literature comes from a single research group, so independent replication is limited [18]. The compound probably does something useful in skin at the topical cosmetic level; the broader anti-aging marketing claims outpace what controlled human trials have shown.
What is the difference between GHK and GHK-Cu?
GHK is the free tripeptide (glycyl-histidyl-lysine) without bound copper. GHK-Cu is the copper-chelated form. The copper coordination is required for most of the documented bioactivities — MMP-2 stimulation in cell studies, for example, does not reproduce with the copper-free form [21]. Products and solutions where the copper is not properly bound may behave differently from what the research describes. The copper-bound form is what most of the published literature and cosmetic evidence actually tests.
What is thymosin alpha 1?
Thymosin Alpha-1 (thymalfasin, also written Tα1) is a 28-amino-acid N-terminally acetylated peptide cleaved from the precursor prothymosin alpha. It acts at the innate-adaptive immune interface, signaling through Toll-like receptors (TLR2, TLR9) on dendritic cells and monocytes to promote T-cell maturation and Th1 polarization. It is approved as a drug (thymalfasin) in more than 35 countries for viral hepatitis and other indications, but is not FDA-approved for marketing in the United States [24].
What does thymosin alpha 1 do?
Thymosin Alpha-1 promotes dendritic-cell maturation, antigen presentation, and T-cell differentiation — essentially nudging a depleted or dysregulated immune system toward a more effective response. In a retrospective COVID-19 cohort, it was associated with lower mortality (11.1% vs 30.0%) and reversal of T-cell exhaustion [25]. In cancer research it has been used as an immunostimulatory adjuvant alongside chemotherapy and checkpoint inhibitors [26]. However, the 2025 Phase 3 TESTS trial in 1,106 sepsis patients found no significant mortality reduction (HR 0.99, P=0.93) [23].
What is thymosin alpha 1 used for?
In countries where it is approved, thymalfasin has been used primarily for chronic viral hepatitis B and C. Published research also covers its use as an adjuvant in cancer therapy [26], in sepsis (the evidence is now mixed [23][27]), in COVID-19, and in general immune-reconstitution contexts after chemotherapy. In the United States, it is not approved for any of these indications and is available only as a research chemical or through compounding.
Is thymosin alpha 1 FDA-approved?
No — not for marketing in the United States. Thymalfasin (the synthetic drug form) is approved in 35+ other countries, but has no US marketing authorization. Thymosin Alpha-1 is distinct from TB-500 (thymosin beta-4) — a different molecule, different mechanism, different evidence base. Conflating the two is a common error. In the US, it is classified as an unapproved research chemical for non-clinical use [24].
What is NAD supplement used for?
NAD+ (nicotinamide adenine dinucleotide) and its oral precursors NMN and NR are marketed and studied primarily for cellular energy metabolism, DNA repair support, and potential longevity benefits. NAD+ declines in tissues with age, and precursors reliably raise blood NAD+ in human trials [29][32]. A 2023 multicenter RCT of NMN (300–900 mg/day) in middle-aged adults improved walking distance and quality-of-life scores versus placebo [29]. Clinical translation to hard longevity or disease endpoints in humans remains unproven [28].
What is the downside of taking NAD+?
Oral NAD+ itself is poorly absorbed intact — most experts consider NMN or NR more rational oral approaches, since plain NAD+ capsules may largely degrade before reaching cells. IV NAD+ wellness infusions are marketed aggressively but rest on minimal controlled evidence; infused NAD+ is cleared rapidly and infusions can cause chest or abdominal discomfort, flushing, and nausea if run too fast. Compounded injectable NAD+ has been subject to FDA recall for elevated bacterial endotoxin. A theoretical concern that raising NAD+ could fuel existing cancer metabolism exists, though NAD+ plays context-dependent roles in oncology. Supplement-grade products vary in purity.
Is it safe to take NAD daily?
Oral NR at doses up to 1000 mg/day for 8 weeks showed no significant adverse events versus placebo in a double-blind RCT in healthy overweight adults [32]. NMN at 300–900 mg/day for 60 days also showed no safety issues in the 2023 multicenter trial [29]. There are no long-term (multi-year) human safety data for sustained high-dose supplementation. The key distinction for safety is the route: oral supplements have a reasonable short-term safety record; IV or injectable NAD+ is a separate risk category because of contamination risk and rapid hemodynamic effects if infused too quickly.
Does NAD cause weight gain?
No weight gain was reported in the human RCTs of NMN [29][30] or NR [32]. The NMN trial in prediabetic women showed no change in body composition alongside improved muscle insulin sensitivity [30]. Raising NAD+ levels addresses energy metabolism at the cellular level and is not associated with weight gain in the published evidence. Some community discussions confuse NAD+ with anabolic compounds — it is a coenzyme, not a hormone or a growth factor.