AHK-Cu (Copper Tripeptide-3)
What it’s used for
AHK-Cu (copper tripeptide-3) is a small copper peptide, related to but different from GHK-Cu. People apply it to the scalp for hair growth and to skin for collagen and repair; some inject it under the skin, usually 1–2 mg a day. The evidence is lab-only: it helped human hair follicles grow in culture, but no clinical scalp trial exists.
- Hair growth Lab & animal research In lab-grown human hair follicles, it lengthened follicles and boosted growth of dermal papilla cells.
- Skin regeneration Community reports Used on skin for collagen, fibroblast support, regeneration and cell survival.
What to expect
- Weeks 2–4
Some shedding
- Months 1–2
Fine new hairs
- Months 2–3
Visible growth
- Months 3–6
Better density
- Months 6–12
Full results
- Skin · Weeks 4–8
Skin changes
Side effects & safety
Side effects
- Hair shedding around weeks 2–4 of scalp use
Stop and get help if
- Burning or itching that won't go away, rash, swelling or skin discoloration
- Shedding that lasts beyond 4–6 weeks
- Metallic taste, nausea or abdominal pain
- Signs of infection
Which symptoms mean call 911 or see a doctor
Avoid or check first if
- Already taking copper supplements — risk of too much copper
In sport
No ruling under WADA’s rules. A cosmetic copper peptide never approved as a drug, which fits S0’s wording. But USADA says most peptides in cosmetics aren’t prohibited, and no anti-doping body has ruled on AHK-Cu or on injecting it.
Which peptides are banned in sport
How much people take
Injectable
Injectable
- Hair & skin Once daily · under the skin · 8–12 weeks 1–2 mg
- Scalp injections by a practitioner Weekly sessions · Tiny injections into the skin 0.1–0.5 mg per injection site
- Research protocol (theoretical) 2–3× weekly · under the skin 1–5 mg
Similar doses appear in 4 other sources
Topical
- Hair growth - scalp application Once or twice daily · Topical to scalp 0.5–1% solution/serum
- Hair growth - combined protocol Once or twice daily · Topical to scalp 0.3–0.5% AHK-Cu with minoxidil
- Skin regeneration - face & body Once or twice daily · Topical to skin 0.3–1% in serum/cream
- DIY formulation Cool-down phase (<40°C / <104°F) · Custom formulation Add 0.3–1% to water phase
Similar doses appear in 4 other sources
How to mix and store it
How many units do I draw?
Injectable
Injectable
How to mix 5 steps with bacteriostatic water
How to mix
- 1 Wipe both tops Wash your hands, then swab the rubber tops of the peptide vial and the water vial with alcohol. Let them dry.
- 2 Draw the water Use bacteriostatic (BAC) water — sterile water with a preservative, sold for mixing peptides . With a new sterile syringe, draw the amount your product calls for. A 1 mL syringe filled twice is 2 mL.
- 3 Run it down the wall Push the needle into the peptide vial at an angle and let the liquid trickle down the glass, not onto the powder.
- 4 Swirl, don’t shake Gently swirl or roll the vial until the liquid is completely clear. Give it a few minutes if needed.
- 5 Label the vial Write the date and what you mixed (for example 5 mg + 2 mL) on the vial.
This is general practice. If your product came with its own diluent or instructions, follow those. Not sure what to buy? See the supplies checklist .
Injecting under the skin Where, rotating sites, which syringe
- Where: belly (at least 2 in / 5 cm from the navel), front of the thigh, or back of the upper arm.
- Rotate sites each time and skip bruised, scarred or sore skin.
- Syringe: most people use a U-100 insulin syringe with a short, thin needle (29–31 gauge, 8 mm or shorter).
- How: wipe with alcohol and let it dry, pinch the skin, go in at 45–90°, push slowly. Use each syringe once.
General practice for under-the-skin injections, not specific to AHK-Cu (Copper Tripeptide-3).
The full guide: how to inject safely
Storage
Fridge · 14–21 days Reported shelf life, not lab-tested. Mixed vial at 2–8°C (35.6–46.4°F), use within 14–21 days
Topical
How to mix 5 steps with distilled water
How to mix
- 1 Wipe both tops Wash your hands, then swab the rubber tops of the peptide vial and the water vial with alcohol. Let them dry.
- 2 Draw the water Use distilled water . With a new sterile syringe, draw the amount your product calls for. A 1 mL syringe filled twice is 2 mL.
- 3 Run it down the wall Push the needle into the peptide vial at an angle and let the liquid trickle down the glass, not onto the powder.
- 4 Swirl, don’t shake Gently swirl or roll the vial until the liquid is completely clear. Give it a few minutes if needed.
- 5 Label the vial Write the date and what you mixed (for example 5 mg + 2 mL) on the vial.
This is general practice. If your product came with its own diluent or instructions, follow those. Not sure what to buy? See the supplies checklist .
Storage
Fridge · 30 days Reported shelf life, not lab-tested. Keep mixed solution at 2–8°C (35.6–46.4°F), away from light, and use within 30 days
Combining it with others
AI assessment Based on how each compound works, not on studies of the combination. How we assess
Use caution 2
- Vitamin C serums Strong acids can break down copper peptides. Use them at different times of day.
- GHK-Cu Both deliver copper. If injecting, use one; layering on the skin is lower risk.
Can be combined 8
- SNAP-8 Different targets: expression lines versus skin repair. Fine to layer on the skin.
Thymosin alpha-1 LL-37 ARA 290 BPC-157 TB-500 Thymosin beta-4 KPV
What the research says
Mostly animal studies
- Evidence comes from human hair follicles grown in a lab; no controlled scalp-growth trial exists.
- Lab follicle and cell studies can't show whole-body toxicity or how well the scalp tolerates it.
- Long-term and injection safety are unknown, and how a solution looks doesn't show it's sterile.
- GHK-Cu research doesn't apply directly — the two have different amino-acid sequences.
- Lab results don't confirm home-made formulas or combining with minoxidil.
What studies found
- Cultured human hair follicles Concentrations of 10⁻¹²–10⁻⁹ M promoted follicle elongation and dermal papilla cell proliferation. The reduction in apoptotic cells at 10⁻⁹ M was not statistically significant.
A half-life hasn’t been verified for this compound.
What it’s made of
- Length
- 3 amino acids
- Molecular weight
- 416.9 Da
- Formula
- Not verified
Sequence 3 · N → C
- A
- H
- K
Copper complex; sequence letters describe the peptide ligand.
Sequence and formulation must be confirmed for the exact material; similarly named products are not necessarily interchangeable.
Length and weight come from a reference listing and were not independently confirmed.
Sources
Sources 14
How this page was made
How it may work: Reference describes dermal-papilla growth, VEGF, reduced TGF-beta1, antioxidant and anti-apoptotic signaling.
Other names: Copper tripeptide-3
Preparation in studies: A product-specific preparation or sterility protocol has not been verified.
Research last checked: Oct 12, 2026 (a targeted search, not a full review).
Community doses, how long people take it, timing and storage are compiled with AI from public peptide guides, clinics and forums, cross-checked against other sources where we could, and rewritten in plain language. “Combining it with others” is an AI assessment of how the compounds work. Study notes are written from each paper’s abstract where one exists. How we source
Original source guide