Frag 17-23
BPC-157 Stable Fragment · BPC Fragment 17-23
Frag 17-23 (HGH Fragment 17-23) is a 7-amino-acid sub-fragment of human growth hormone derived from the N-terminal region of the molecule. Distinct from the much better-known HGH Frag 176-191 (C-terminal lipolytic fragment), Frag 17-23 corresponds to the disulfide-loop region of GH and is researched for putative effects on glucose regulation rather than lipolysis.
Inject fasted morning. Reconstitute with bacteriostatic water; refrigerate. The compound is poorly characterized - approach experimentally, monitor blood glucose during early use, and have carbohydrate available in case of unexpected hypoglycemia.
Start here. Every protocol below is ordered lowest-first. Begin at the smallest effective dose, hold about a week to assess tolerance, and step up only if needed.
How it works
Frag 17-23 mechanism of action is poorly characterized. The 17-23 region of human growth hormone falls within the small disulfide-loop near the N-terminus of the molecule. Proposed mechanisms in the limited literature include:
Hypoglycemic Action
Some reports suggest the fragment may reproduce a portion of GH's acute insulin-like / hypoglycemic effect (distinct from GH's broader insulin-antagonist action at higher doses). The mechanism is unclear and the effect size in any controlled study is unestablished.
No Receptor Identified
Unlike HGH Frag 176-191 (which acts via β3-adrenergic receptor), no specific receptor has been published for Frag 17-23. This is a major caveat - efficacy claims rest on a poorly-defined mechanism.
Short Plasma Half-Life
~30-60 minutes by analogy with other small HGH fragments. Daily dosing typical based on community protocols.
Not Met-Containing
The 17-23 sequence does not contain methionine, so the GHK-Cu chemistry conflict does not apply (unlike Frag 176-191).
What to expect
Week 1-2: minimal subjective effect; possible mild glucose changes.
Week 4-8: theoretical metabolic adaptation - effect size unknown in humans.
Week 8-12: cumulative effects difficult to attribute to the peptide vs other lifestyle factors.
Evidence
Claims we could not support
No abstract we checked supports these for this molecule at this route. That is not the same as saying they are false — it marks where the evidence is missing.
Molecular identity. The page conflicts among GH 17-23, thymosin-beta-4 Ac-LKKTETQ, and BPC-related aliases; exact matching is impossible.
Dose/route: 200 mcg SubQ daily. No abstract administered one unambiguous matching molecule at this regimen.
Glucose/hypoglycemia mechanism and safety. Thymosin-beta-4 17-23 papers concern actin binding/wound repair and were rejected as mismatches.
Side effects & safety
Commonly reported
- Injection site reaction (mild)
- Possible mild hypoglycemia in fasted state
- Mild headache (early doses)
Less common & notes
- Hypoglycemia (more pronounced in users on insulin or sulfonylureas).
- Long-term safety completely uncharacterized - no human exposure outside research-chemical community use.
- Theoretical effects on GH/IGF-1 axis at high doses unknown.
- Allergic reaction to peptide rare.
- Given the sparse literature, side-effect surveillance relies on careful self-monitoring.
Pharmacokinetics
Plasma (estimated by analogy with related fragments)
SubQ
Functional window
subQ moderate (estimated)
Daily dosing typical
Rapid peptidase degradation
Storage. Lyophilized vial: refrigerate (2-8°C / 36-46°F) or freeze (-20°C) for long-term storage. After reconstitution with bacteriostatic water: refrigerate, use within 14-21 days. Light-sensitive. Do NOT shake. Discard if cloudy, discolored, or beyond use-by window.
Regulatory status
Not FDA-approved for any indication. Has not entered Phase 1 clinical trials. Available only as research chemical from peptide-supply vendors. Limited published literature beyond foundational biochemistry studies from the 1980s-90s. WADA prohibited under class S2 (peptide hormones, growth factors) by class effect. Sale for human use is prohibited by FDA regulation.
Put it to work
Calculate, log & track
Open Frag 17-23 straight into OnePin with your vial and dose pre-filled, then let it handle the syringe math and remind you before the vial runs out.
Open Frag 17-23 in the app →Go deeper
The guide & community
The complete Frag 17-23 walkthrough, real protocol discussion and coaching live inside the BlessUp community on Skool.
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