At a Glance
| Feature | Detail |
|---|---|
| What it is | Vendor-made blend of four research peptides in one vial |
| Typical label | GHK-Cu 50 mg + BPC-157 10 mg + TB-500 10 mg + KPV 10 mg (80 mg); amounts can vary by vendor |
| Rationale | GLOW’s remodelling and repair components plus KPV for anti-inflammatory signalling |
| Route | Subcutaneous injection |
| Typical practice dose | About 2 mg GHK-Cu per injection (≈3.2 mg blend; ≈0.4 mg each of BPC-157, TB-500 and KPV), 5–7 days/week, 6–8 weeks |
| Evidence level | Limited: combination untested; KPV has no human data; other components limited to emerging |
| Regulatory status | No component approved by FDA or EMA; all four on FDA’s significant-safety-risk compounding list (GHK-Cu for injection); WADA 2026: prohibited (BPC-157 in S0, TB-500 in S2.3) |
KLOW is the four-peptide upgrade of the GLOW blend. Vendors add KPV, a small anti-inflammatory peptide, to the copper peptide and the two repair peptides, and market the result for skin, gut and recovery. The composition is more consistent across sellers than GLOW’s: independent listings and several lab certificates show the same 50/10/10/10 split (Peptigrity). Its evidence is not stronger.
My verdict: KLOW adds a fourth untested variable to an untested mixture. The KPV component is the least studied of the four, with no human exposure data at all, and it comes along at a dose set by the vendor’s ratio.
The components
| Component | Labelled amount | What the evidence says | Full article |
|---|---|---|---|
| GHK-Cu | 50 mg | Copper tripeptide; controlled topical skin data, no trials of injection [3] | GHK-Cu |
| BPC-157 | 10 mg | Mostly rat data; 3 small human studies (30 participants), very low certainty [2] | BPC-157 |
| TB-500 | 10 mg | Thymosin beta-4 fragment or analogue; angiogenesis and wound healing in animals [4] | TB-500 |
| KPV | 10 mg | Lys-Pro-Val, the C-terminal tripeptide of alpha-MSH; taken up via the PepT1 transporter and reduced colitis in mice [5]; FDA reports no human exposure data [8] | KPV |
The only human data involving any two of these together is a 16-patient retrospective series of intra-articular BPC-157 with or without thymosin beta-4 for knee pain [1]. Nothing has tested all four. KPV’s best-known data concern intestinal uptake in mouse colitis [5]; whether a subcutaneous dose of about 0.4 mg does anything for gut inflammation is unknown.
Stability and quality concerns
- Independent tests. One independent tester lists 19 KLOW tests across 8 vendors: 9 passed, 6 failed and 4 were incomplete (Finnrick). Another aggregator lists over 100 KLOW tests with high average purity but notes that whole-vial purity can hide a component that is off-label; in one lot, BPC-157 measured about 22 % above its labelled amount (Peptigrity).
- Overfill and calculated values. Some certificates show vials well above the label; others report per-peptide amounts calculated from the manufacturer’s ratio rather than measured.
- Copper in a shared vial. GHK-Cu is reasonably stable in water but degrades under oxidative and alkaline stress [6], and copper can catalyse oxidation of susceptible amino acids such as histidine [7]. The only stability data on KLOW after reconstitution come from a single vendor-run, non-peer-reviewed test of one vial over 30 days.
- TB-500 identity. Certificates for some blends list full-length thymosin beta-4 rather than the short fragment; the full-length protein contains oxidation-prone methionine.
Dosing
For informational purposes only — this summarises doses used in research and practice; it is not a prescription or individual medical advice.
| Goal | Dose | Route | Frequency / timing | Cycle length | Basis |
|---|---|---|---|---|---|
| Skin, recovery, inflammation (standard) | About 2 mg GHK-Cu per injection (≈3.2 mg blend; ≈0.4 mg each of BPC-157, TB-500 and KPV) | SC | 5 days on, 2 off, or daily | About 6–8 weeks, then a break | Practice protocol (PeptideMind, r/PeptideGuide) |
| Higher variant | About 2.5 mg GHK-Cu (≈0.5 mg each of the others) | SC | Daily | About 40 days | Anecdotal (r/PeptidePathways, r/PeptideGuide) |
| Low, long variant | About 1 mg GHK-Cu | SC | Every other day | About 100 days | Anecdotal (same r/PeptideGuide thread) |
| Separate peptides, for comparison | GHK-Cu 1–2 mg/day; BPC-157 250–500 mcg/day; TB-500 2–5 mg 2×/week; KPV 500 mcg–1 mg/day | SC (KPV also oral) | As stated | 4–12 weeks | Practice protocol (see the stacking guide) |
The fixed ratio drives everything. Dosing for 2 mg of GHK-Cu gives about 0.4 mg KPV, below the 0.5–1 mg commonly used when KPV is taken alone, and about 2.8 mg TB-500 a week spread over daily injections. Raising the dose to reach a KPV or TB-500 target also raises the copper peptide, which most users blame for the sting.
For injection technique and reconstitution, see the peptide injection guide.
What people report: what works and what doesn’t
Reported to work
- Skin quality, healing after procedures and less joint pain, described in detailed single-user write-ups that also involved other changes (r/Biohacking).
Mixed or unclear
- Whether KLOW does anything GLOW does not; no user comparison isolates the KPV component.
- Daily versus 5-days-a-week schedules and cycle length.
Reported not to work, or disappointing
- Painful, delayed injection-site reactions with red, itchy bumps, as with GLOW (r/Peptides_for_Women).
- Systemic effects that led some users to stop: nausea and anxiety (r/PeptidePathways); hot flashes and sweating (r/PeptidePathways); palpitations, insomnia and feeling “wired” (r/BiohackingU); worse sleep and erectile quality (r/Biohacking).
What a proper trial would need to show: that the four-peptide blend beats GLOW, GHK-Cu alone and placebo on a measured outcome, and that the KPV component is active and safe when injected.
Safety and legal status
The unknowns of four peptides add up, and a side effect cannot be traced to any one of them. BPC-157 and thymosin beta-4 promote blood vessel growth and cell migration [4], a reason for caution with current or past cancer. Injected copper peptides are unsuitable for people with Wilson’s disease or other copper disorders. KPV is a melanocortin fragment; its effects on pigmentation or other melanocortin pathways after injection have not been studied.
- United States. None of the components is an approved drug. FDA’s page on bulk substances that may present significant safety risks lists BPC-157, TB-500, KPV (noting no human exposure data) and GHK-Cu for injectable use [8].
- EU and Germany. No component is authorised as a medicine; supply for human use is supply of an unauthorised medicinal product.
- Sport. Prohibited at all times: BPC-157 is named in WADA S0 and TB-500 in S2.3; KPV, as a non-approved substance, also falls under S0 [9].
Related Articles
- GLOW Peptide Blend: GHK-Cu, BPC-157, TB-500 in One Vial
- KPV: The Anti-Inflammatory Tripeptide
- Peptide Stacking: Combining BPC-157, TB-500 and GHK-Cu
- GHK-Cu: The Copper Peptide for Tissue Remodeling
- Tri-Heal Max Blend: TB-500, BPC-157 and KPV
- Peptide Sourcing: Quality and Grey-Market Risks
Frequently asked questions
What is in the KLOW blend?
The usual label is 80 mg per vial: 50 mg GHK-Cu, 10 mg BPC-157, 10 mg TB-500 and 10 mg KPV. Component amounts can differ between vendors, so the per-peptide figures on the vial matter more than the name.
What is the difference between KLOW and GLOW?
KLOW contains the same three peptides as the common GLOW formula (GHK-Cu, BPC-157, TB-500) plus 10 mg of KPV, a tripeptide fragment of alpha-MSH studied for gut inflammation in mice.
How is KLOW dosed?
Practice protocols dose by the copper peptide: about 2 mg GHK-Cu per injection, which in an 80 mg vial means about 3.2 mg of blend and about 0.4 mg each of BPC-157, TB-500 and KPV, usually 5 days a week or daily for 6–8 weeks. These are community conventions, not trial doses.
Is KLOW safe?
Its safety has not been studied. Users most often report painful injection sites; some report nausea, anxiety, palpitations, hot flashes or poor sleep. Independent lab tests of KLOW vials show a substantial share failing or with components off-label.
References
- Lee E, Padgett B. Intra-Articular Injection of BPC 157 for Multiple Types of Knee Pain. Altern Ther Health Med. 2021. PMID: 34324435. https://pubmed.ncbi.nlm.nih.gov/34324435/
- Poolton JT, Minett J, Kazmi A. Human evidence for BPC-157 in orthopaedic and regenerative medicine: a systematic review of efficacy and safety. Acta Orthop Belg. 2026. PMID: 42885452. https://pubmed.ncbi.nlm.nih.gov/42885452/
- Pickart L, Vasquez-Soltero JM, Margolina A. GHK Peptide as a Natural Modulator of Multiple Cellular Pathways in Skin Regeneration. Biomed Res Int. 2015. PMID: 26236730. https://pubmed.ncbi.nlm.nih.gov/26236730/
- Philp D, Goldstein AL, Kleinman HK. Thymosin beta4 promotes angiogenesis, wound healing, and hair follicle development. Mech Ageing Dev. 2004. PMID: 15037013. https://pubmed.ncbi.nlm.nih.gov/15037013/
- Dalmasso G, Charrier-Hisamuddin L, Nguyen HT, et al. PepT1-mediated tripeptide KPV uptake reduces intestinal inflammation. Gastroenterology. 2008. PMID: 18061177. https://pubmed.ncbi.nlm.nih.gov/18061177/
- Badenhorst T, Svirskis D, Wu Z. Physicochemical characterization of native glycyl-l-histidyl-l-lysine tripeptide for wound healing and anti-aging: a preformulation study for dermal delivery. Pharm Dev Technol. 2016. PMID: 25384620. https://pubmed.ncbi.nlm.nih.gov/25384620/
- Khossravi M, Borchardt RT. Chemical pathways of peptide degradation: IX. Metal-catalyzed oxidation of histidine in model peptides. Pharm Res. 1998. PMID: 9688066. https://pubmed.ncbi.nlm.nih.gov/9688066/
- U.S. Food and Drug Administration. Certain Bulk Drug Substances for Use in Compounding that May Present Significant Safety Risks. Content current as of 22 April 2026. https://www.fda.gov/drugs/human-drug-compounding/certain-bulk-drug-substances-use-compounding-may-present-significant-safety-risks
- World Anti-Doping Agency. The 2026 Prohibited List (S0; S2.3), as published in Tractatenblad 2026, 25. https://zoek.officielebekendmakingen.nl/trb-2026-25.html
Disclaimer: This article is for information and education only and is not a prescription or individual medical advice. KLOW and its components are not approved medicines.
