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peptide comparison · skin & hair × metabolic

GHK-Cu vs Retatrutide

Two compounds, mechanism by mechanism. Where they overlap, where they don't, and which vendors stock each.

§ 01

Mechanism

ghk-cu

GHK-Cu

Copper peptideGlycyl-L-histidyl-L-lysine-Cu

Naturally occurring copper-binding tripeptide. Well-documented in dermatology literature for collagen synthesis and wound healing.

Full guide →
vs
retatrutide

Retatrutide

LY3437943GLP-3triple-G

Triple agonist of GLP-1, GIP, and glucagon receptors. Eli Lilly's Phase 3 candidate (TRIUMPH program).

Full guide →
§ 02

Key facts

factGHK-CuRetatrutide
category
·skin & hairmetabolic·
half-life
·—~6 days·
research dosing
·Topical at 0.05–0.2% concentration; subcutaneous research uses 1–2 mg.Research literature cites 1–12 mg weekly subcutaneous in dose-escalation studies.·
trending
search demand
○72/10095/100●
vendors stocking
·11·
aliases
·Copper peptide · Glycyl-L-histidyl-L-lysine-CuLY3437943 · GLP-3 · triple-G·
§ 03

Use-case overlap

only ghk-cu
  • skin regeneration
  • hair growth
  • anti-aging
both

none

only retatrutide
  • weight loss
  • metabolic dysfunction
  • fatty liver
§ 04

Where to buy

ghk-cu
GHK-Cu
1 verified vendor
Particle Peptides
See all vendors →
retatrutide
Retatrutide
1 verified vendor
Limitless Life Nootropics
See all vendors →
§ 05

Sources

  1. [01]GHK Peptide as a Natural Modulator· GHK-Cu
  2. [02]Triple–Hormone-Receptor Agonist Retatrutide for Obesity (NEJM)· Retatrutide
  3. [03]Lilly TRIUMPH Phase 3 announcement· Retatrutide
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