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GHK-Cu

peptide

Copper tripeptide-1

Skin / repair peptide (topical cosmetic; injectable unapproved)

Research status · Cosmetic (topical)

Topical GHK-Cu is used widely in cosmetics (regulated as a cosmetic, not a drug). Injectable GHK-Cu is not FDA-approved and was flagged as higher-risk in FDA compounding review.

GHK-Cu is a copper-binding peptide. In topical skincare it is mainstream and regulated as a cosmetic. Injectable use is a different, unapproved risk category and needs clinician oversight.

How it works

Copper-binding peptide involved in skin remodeling and antioxidant signaling; supports collagen-related pathways (topical evidence strongest).

Commonly discussed use cases

  • Skin appearance (topical)
  • Hair (discussed)
  • Wound-healing perception (discussed)

Supposed / potential benefits

  • Topical: supported cosmetic skin benefits
  • Injectable claims are not well established

Common side effects

  • Skin irritation/redness (topical)
  • Injection-site reactions (injectable)
  • Rare allergic reaction

Warnings & contraindications

  • Injectable form is not FDA-approved and higher-risk
  • Topical cosmetic use is the well-characterized route

Typical timing considerations

Topical products are used per label (often daily). Any injectable use should be clinician-directed.

Administration route

Topical (cosmetic) or subcutaneous injection (unapproved)

Storage

Topicals per product label; injectables refrigerated per pharmacy instructions.

Questions to ask your clinician

  • Is topical appropriate for my goal instead of injectable?
  • How would we evaluate whether it's working?

Commonly tracked in Reta

Weekly photo noteSkin/site reactionsApplication consistency

Tracking fields organize user-entered, clinician-directed routines — Reta never recommends or computes doses.

Sources

Track this in Reta

Beta members get a ready-made tracker for GHK-Cu — schedule, dose log, injection-site rotation, reminders, and check-ins — for organizing a clinician-directed routine. Personal tracking is available to everyone during the Public Beta.

Reta is a tracking and education tool — not a medical provider. Nothing here is a diagnosis, treatment, prescription, or dosing recommendation. Peptides and medications should only be used under the direction of a licensed clinician. Talk to a qualified clinician before starting, stopping, combining, or changing anything. Many compounds below are not FDA-approved for human use; some are investigational or sold through unregulated channels where purity and dosing are not guaranteed.