RESEARCH PEPTIDE FUNDAMENTALS / FAQ
Questions From the Research Record
Direct answers, cited to the source, to the questions readers most often bring to these three research peptides.
What does BPC-157 do in the body?
In animal studies, BPC-157 accelerates healing across a range of tissues — gastric ulcers, tendons, ligaments, and blood vessels — largely by promoting angiogenesis (new blood-vessel growth) through the VEGFR2 receptor pathway [4]. It has also been shown to speed ulcer healing in rats, with intramuscular delivery working better than oral (intragastric) delivery in the same experiments [5]. Human evidence is far thinner: a two-person intravenous safety pilot found no adverse effects at doses up to 20 mg, but did not test for any specific benefit [1]. Most of what's known comes from rodent and cell-culture models, not people.
Is BPC-157 a growth hormone?
No. BPC-157 is not a growth hormone and doesn't act through the growth-hormone-releasing pathway the way CJC-1295 does. It's a gastric-juice-derived cytoprotective peptide whose repair effects are linked mainly to angiogenesis (VEGFR2 signaling) [4], with a separate reported effect of sensitizing growth-hormone-receptor signaling specifically in cultured tendon fibroblasts — a narrow, tissue-specific finding, not evidence that BPC-157 itself raises growth hormone in the body.
Does BPC-157 work immediately?
There's no published human efficacy timeline to answer this precisely — the human literature is limited to a safety pilot, not an effects study [1][2]. In research-use communities, people who report benefit for tendon, ligament, or joint problems typically describe noticing a difference within one to three weeks, not immediately. That's an anecdotal pattern from community reports, not a documented clinical timeline.
Does BPC-157 damage the liver?
The published human safety data doesn't show it does: the two-person intravenous pilot found no measurable changes in hepatic (liver) biomarkers at doses up to 20 mg [1]. That's a very small sample, though, and a 2025 review explicitly cautions that rigorous large-scale human trials are lacking [2] — so "no liver damage in two people" is a reassuring but limited finding, not proof of long-term liver safety at any dose or by any route.
What is CJC-1295?
CJC-1295 is a synthetic analog of growth-hormone-releasing hormone (GHRH), built on the first 29 residues of the natural hormone with four stabilizing substitutions. It comes in two forms: "CJC-1295 DAC," chemically bound to blood albumin so it lasts for days, and short-acting "no-DAC" (Modified GRF 1-29). Every published human study of either form used subcutaneous injection [9][10].
What does CJC-1295 do?
It binds the GHRH receptor on pituitary cells, triggering synthesis and pulsatile release of growth hormone, which raises liver IGF-1 [6]. In human studies, single subcutaneous doses raised GH 2- to 10-fold for six or more days and IGF-1 1.5- to 3-fold for 9-11 days, with the normal pulsatile pattern of GH release preserved rather than flattened [9][10].
Is CJC-1295 safe?
CJC-1295 is not approved for human use anywhere, and published human safety data is limited to a small number of early pharmacology studies in healthy adults — not large or long-term trials [9][10]. Sustained IGF-1 elevation carries a theoretical, epidemiology-based cancer concern, and 2024 FDA briefing materials flagged immunogenicity as a concern when reviewing the compound for a pharmacy-compounding pathway [6]. The original long-acting development program was discontinued. None of this establishes that CJC-1295 is unsafe at any particular dose — it establishes that the safety question hasn't been answered by rigorous human trials.
How much CJC-1295 should I take?
This site doesn't answer that question, for anyone, under any circumstance — it's not a source of dosing guidance or medical advice. What the published literature reports are the specific doses used in human pharmacology studies: single subcutaneous doses of 30-90 micrograms/kg in the trials that exist [9][10]. Those are study parameters, not recommendations, and they don't establish what dose, if any, would be appropriate for a person outside a clinical research setting.
What is semaglutide?
Semaglutide is a synthetic GLP-1 receptor agonist — a modified version of a gut hormone that signals fullness after eating. It's FDA-approved for type 2 diabetes, chronic weight management, cardiovascular-risk reduction, and, since 2025, MASH, available as both a once-weekly subcutaneous injection and a once-daily oral tablet [15].
What is semaglutide used for?
Its FDA-approved uses include lowering blood glucose in type 2 diabetes, reducing body weight in chronic weight management, reducing major cardiovascular events in adults with established cardiovascular disease and overweight or obesity, and treating MASH [13][14]. In research, it has also reduced kidney-disease events in type 2 diabetes with chronic kidney disease [12].
How does semaglutide work?
It activates GLP-1 receptors throughout the body: in the pancreas, boosting glucose-dependent insulin release and suppressing glucagon; in the gut, slowing stomach emptying; and in the brain, acting on hypothalamic and brainstem circuits that regulate appetite [16].
How does semaglutide work for weight loss?
The weight effect is mostly central: semaglutide reaches brain regions including the arcuate nucleus and area postrema, activating fullness-signaling neurons and suppressing hunger-signaling ones, which reduces food intake and shifts food preference without lowering energy expenditure [16]. In the STEP 1 trial, injected semaglutide produced -14.9% mean body-weight change at 68 weeks versus -2.4% with placebo [14].