Blend safety notes
KLOW is a four-peptide research blend — GHK-Cu 50mg, BPC-157 10mg, TB-500 10mg and KPV 10mg per 80mg vial. No study has evaluated the combination. What follows is the known and unknown safety picture for each part, and nothing invented to fill the gaps.
Research-use information only. KLOW is not approved for human use anywhere, and none of its components has a controlled human safety trial by injection. This page does not provide dosing or medical advice.
Known: The best-characterised component. Topical GHK-Cu has been used in human skin studies for decades with a benign tolerability record. Injectable use is far less studied; the copper load matters — 50mg of GHK-Cu carries roughly 8mg of copper — and site irritation is the most commonly reported issue in informal reports.
Not known: No controlled human safety data for subcutaneous GHK-Cu at this mass; copper accumulation with repeated dosing has not been characterised.
Known: Rodent studies report few adverse findings, and a small number of early human tolerability reports exist. In September 2023 the FDA placed BPC-157 in Category 2 of its bulk-substances evaluation, citing insufficient safety data (not evidence of harm) — a regulatory flag, not a finding.
Not known: No controlled human safety trial. Long-term effects of an angiogenic peptide are theoretically relevant to anyone with a tumour history and have not been studied.
Known: TB-500 is a synthetic fragment of thymosin-β4. Full-length thymosin-β4 has been through human trials (cardiac and corneal) with an acceptable safety profile; the fragment itself has no human data.
Not known: Whether the fragment shares the parent's tolerability is assumed, not shown. The same theoretical angiogenesis caveat as BPC-157 applies.
Known: A three-amino-acid fragment of α-MSH. Rodent colitis studies report no adverse signals; KPV lacks α-MSH's pigmentary effect.
Not known: No human pharmacokinetic or safety data for injected KPV. The July 2026 FDA advisory vote concerned compounding eligibility, not safety review.
Reconstituting to a literature-typical BPC-157 or TB-500 amount fixes a GHK-Cu amount five times larger. The copper load scales with it.
Interactions between the four peptides — pharmacokinetic or pharmacodynamic — have not been studied. Additive site irritation is the most plausible interaction.
BPC-157 and TB-500 both promote new blood-vessel growth in animal models. That is the mechanism of interest for repair research and the theoretical concern for anyone with a tumour history.
Purgo screens KLOW as a full formula. If per-component quantitation matters to your model, request the certificate before use.
No. KLOW is a supplier-defined blend and no study has evaluated the four peptides together. Everything on this page is inferred from data on the individual components.
For any injected research peptide: injection-site redness, swelling or pain, and the possibility of hypersensitivity reactions. Specific to KLOW, the 50mg GHK-Cu component is the one with a plausible dose-related concern (copper load and site irritation).
No. An earlier version of this page wrongly described KLOW as kisspeptin-10. Kisspeptin is a separate Purgo product with its own profile; KLOW is GHK-Cu + BPC-157 + TB-500 + KPV.
Yes. The blend is 5:1:1:1 by mass. Reconstituting to reach a literature-typical amount of one component fixes the amount of the other three — most notably, dosing BPC-157 or TB-500 to common research amounts means a large GHK-Cu dose alongside.