AHK-Cu
A copper-bound tripeptide (alanine-histidine-lysine) engineered for the hair follicle. People apply it to the scalp for thicker, fuller-looking hair, to support the follicles that drive growth, often layered with GHK-Cu or minoxidil.
Where to buy AHK-Cu, cheapest first.
Prices from 2 vendors across the market. We link straight to each vendor’s product page and grade vendors on public lab data, so you’re not just chasing the lowest number.
What AHK-Cu actually does.
The simple version first, then a little more for the curious. No biochem degree required.
It feeds copper to the cells at the base of each follicle, the ones that decide how thick your hair grows and how long it keeps growing, helping them stay alive and active longer.
How it works
AHK-Cu is a tripeptide carrier that delivers copper to dermal papilla cells, the control center at the base of each follicle. In lab work it helped those cells survive and multiply, lowering the cell-death signals (caspase-3 and PARP) that otherwise shrink a follicle.
Where it acts
It works locally in the scalp, right at the follicle, rather than circulating through the body. That is why it is formulated as a topical serum and not an injection, the action is meant to stay where you apply it.
What people notice
Reports center on slower shedding, thicker-feeling strands, and gradually fuller coverage over months. Hair biology is slow, so people typically run it three to six months before judging anything.
Honest caveat: the supporting evidence is mostly in-vitro and animal work, including a 2007 study on human follicles in culture. There is little controlled human trial data, and effects depend heavily on concentration, since very high levels were inhibitory in the lab. AHK-Cu is not an approved medicine and is sold strictly for research use only. None of this is medical advice, talk to a licensed provider before starting anything.
How to take it.
AHK-Cu is applied topically to the scalp as a serum or solution. There is no injecting and no reconstitution, you apply drops directly where you want growth. The routine is below; for layering with minoxidil or GHK-Cu and for cycle length, see the full guide.
Clean the scalp
Apply after washing and towel-drying, to a clean, damp-to-dry scalp. A clean surface helps the serum reach the follicle instead of sitting on product buildup.
Apply the serum
Place 3 to 5 drops of a 1 to 2 percent solution directly on the thinning areas. Start at the low end (0.5 to 1 percent) for the first few weeks so your scalp can adjust.
Massage and let it absorb
Massage gently in circles for 5 to 10 seconds to spread it and boost blood flow. Let it absorb, wait about 15 minutes before layering anything else, and do not rinse.
Stay consistent and store it
Use once or twice daily, evening is a common choice. Keep the bottle cool and out of light, and refrigerate after opening in hot climates. Results build over months, not days.
Typical AHK-Cu dose: a 1 to 2 percent topical serum, 3 to 5 drops applied to the scalp once or twice daily. Start lower (0.5 to 1 percent) and build up. Concentrations above 2 percent are rarely needed and raise the risk of irritation. Run it consistently for three to six months before judging.
How to cycle AHK-Cu.
How long people run AHK-Cu, when to take a break, and the honest reasoning behind it.
Run consistently for months before judging.
Unlike injectable peptides that people run in defined on-and-off cycles, AHK-Cu is usually applied continuously, the way you would use any leave-on scalp treatment. The follicle only stays supported while you keep applying it, so there is no built-in loading or break structure.
The practical limit is your scalp's tolerance. If you get persistent redness or itching, that is the signal to pause or drop the concentration, not a fixed calendar. Many people simply apply daily for as long as they want to maintain results.
- Apply consistently rather than in bursts, since the follicle support fades when you stop.
- Give it three to six months before deciding whether it is working. Slower shedding shows up before visible thickening.
- Pause or lower the strength if irritation sets in, and resume once your scalp settles. Persistent problems are a conversation for a licensed provider.
Want the full picture, on and off periods, the washout, stacking, and keeping your results? Read how peptide cycling works →
What's actually in the vial.
These link to each vendor's general lab-results page. We don't run the labs ourselves and we don't show a purity number unless it's printed on a certificate we link, so you can open the document and check it against the batch yourself.
| Vendor | Purity (per COA) | Batch / report | Certificate |
|---|---|---|---|
| Next Gen Peptides | see lab page | not shown | Lab results ↗ |
What people pair it with.
AHK-Cu is often layered with other topicals rather than run alone. These are the combinations people reach for when hair is the goal.
Hair density
The classic copper-peptide hair combo. AHK-Cu targets the follicle directly while GHK-Cu keeps the surrounding scalp healthy. A typical starting mix is about 1 percent AHK-Cu with 1 to 2 percent GHK-Cu.
View stack →Growth & blood flow
Two different mechanisms layered together. Minoxidil drives blood flow to the follicle; AHK-Cu works on the follicle cells that control growth. Many protocols apply AHK-Cu first, wait 15 to 20 minutes, then minoxidil.
View stack →Full scalp protocol
A layered topical routine for people chasing maximum coverage. The copper peptides support the follicle and scalp while PTD-DBM is studied for reactivating dormant follicles. Patch test and introduce one at a time.
View stack →In the same corner.
Other hair and scalp peptides people compare against AHK-Cu.
Questions, answered straight.
Is AHK-Cu legal?
AHK-Cu is not an approved drug, and it is not sold for human use. The vendors we compare offer it strictly for research use only. It is a topical cosmetic-style peptide rather than a systemic drug, and it is not specifically named on WADA's prohibited list, but rules vary by country, so check what applies where you are.
What does research use only actually mean?
It means the product is sold for laboratory and research purposes, not as a supplement or medicine for people. It has not been reviewed or approved for human use by the FDA. We aggregate prices and public lab data so you can see the landscape; what you do with that is between you and a licensed provider.
How long before AHK-Cu works?
Hair biology is slow. Most people apply it consistently for three to six months before judging results. Slower shedding usually shows up before visible thickening. It is not an overnight change, and stopping early is the most common reason people see nothing.
What concentration should I use?
A 1 to 2 percent topical serum is the common range. It is wise to start lower, around 0.5 to 1 percent, for the first few weeks so your scalp adjusts. Higher is not better here, in lab work very high copper-peptide concentrations actually inhibited follicle growth, so more than 2 percent is rarely worth it.
Can I layer it with minoxidil or GHK-Cu?
Yes, both are common. With minoxidil, many people apply AHK-Cu first, wait 15 to 20 minutes for it to absorb, then apply minoxidil. With GHK-Cu, a typical mix is about 1 percent AHK-Cu plus 1 to 2 percent GHK-Cu. Avoid applying strong vitamin C, high-strength retinoids, or low-pH exfoliants at the same time, as they can degrade the peptide.