GHK-Cu

Copper peptide · A-tier (Dr. Alex Tatem) · Limited evidence

Best known as a skin-care ingredient. The topical data on collagen and wound healing is real. People also inject it for skin, hair and general repair, but no human trials of that use exist.

Dr. Tatem’s take

A-tier. The topical data is strong and anecdotes are “universally positive”, but “we just don’t have high-quality clinical evidence” for injecting it. In his deep dive he calls injectable safety “probably favorable” and flags Wilson’s disease and liver patients.

In Dr. Tatem’s tier list

• Named for its ingredients — glycine, histidine, lysine, plus copper, which helps it get delivered.
• “There’s actually a ton of data supporting GHK-Cu” in topical form for skin tone, “glow,” hydration and collagen repair.
• The new trend is injecting it for a systemic effect (skin, thinning hair). That makes sense scientifically, but drugs don’t always translate: ketoconazole is safe as a shampoo yet toxic to the liver if swallowed. No such signal has appeared for GHK-Cu, but the injectable literature is “extremely sparse.”
• Anecdotes seem “universally positive,” and friends who run it year-round “have pictures to back up their results.”
• Verdict: “a solid A rating… but we just don’t have high-quality clinical evidence.”

History & background

GHK was discovered in 1973 by Loren Pickart, who found that a small peptide in the plasma of young people made aged liver tissue behave more youthfully; its strong affinity for copper (GHK-Cu) was described shortly after.

Through the 1980s–2000s it became a staple cosmetic ingredient for wound healing and anti-aging skin care. Injectable use is a 2020s trend. It was removed from FDA’s Category 2 list in April 2026 and is expected to come before FDA’s compounding advisory committee in a future meeting.

Benefits

• Topical use supports collagen production and wound healing, e.g. recovery after laser resurfacing.
• Changes the activity of many genes involved in tissue repair (lab data).
• User reports on skin and hair are consistently positive.

Risks

• Topical: skin irritation.
• Injected: effects in people haven’t been studied, and copper can build up.
• Avoid with Wilson’s disease or liver disease. Consider checking copper levels if using long-term.

Dosing protocols (informational, labeled by evidence)

• Community (bro science): Forum injectable protocol (per Tatem) — 1–2 mg, SubQ, Daily, 30–60 days
• Community (bro science): Community injectable with off-cycle — 1–2 mg, SubQ, Daily, 4–8 wk on, 2–4 wk off
• Community (bro science): Topical cosmetic use — 0.01–1% cream/serum, Topical (skin, scalp), 1–2x daily, 8–12 wk for skin; 12–24 wk for hair

Status: Not an approved drug; widely used in cosmetics. Removed from FDA’s Category 2 list in April 2026, but not yet approved for compounding.

Grade and commentary: Dr. Alex Tatem. Watch: GHK-Cu: The Peptide Everyone Is Injecting (Big Mistake?), The Truth About Popular Peptides (What Works, What’s Overhyped) | Peptide Tier List pt.1. Subscribe: @DrAlexTatem.