01 · Part and applyApply directly to clean, dry scalp
Part the hair where needed and apply the serum directly along the part or the scalp areas you want to target.
About this serum
AHK-Cu Copper Peptide Hair Serum is a concentrated leave-on scalp formula built around AHK-Cu, a copper-binding tripeptide studied experimentally in human hair follicles and dermal papilla cells.
Each 2 oz (60 mL) bottle is labeled with 4,800 mg of AHK-Cu at an 8% concentration in a distilled-water base. The formula has only two listed ingredients: Distilled Water and AHK-Cu.
The serum's characteristic blue color comes from the copper-peptide complex itself rather than an added dye.
Published AHK-Cu research helps explain why this peptide is used in hair and scalp formulas, but those studies did not test this finished serum on people's scalps.
What you can expect What to expect
- Pure AHK-Cu formula
- Lightweight leave-on scalp application
- Two listed ingredients
- Direct use on targeted scalp areas
Full descriptionWhy AHK-Cu is used in hair products · Why 4,800 mg at 8% · What the evidence does not establish
Why AHK-Cu is used in hair products
AHK-Cu is a copper-binding tripeptide made from alanine, histidine and lysine complexed with copper.
In the best-known direct study, researchers evaluated AHK-Cu in isolated human hair follicles ex vivo and cultured dermal papilla cells in vitro. AHK-Cu stimulated follicle elongation and dermal papilla cell proliferation under those laboratory conditions.
Those findings make AHK-Cu an ingredient of interest in hair-focused scalp care, but they do not establish that this finished serum clinically treats hair loss or regrows hair in people.
Read the full AHK-Cu hair research review
Why this formula contains 4,800 mg at 8%
Each bottle is formulated and labeled to provide 4,800 mg of AHK-Cu, equivalent to an 8% concentration.
This makes it Neurogan Health's highest-concentration pure AHK-Cu leave-on scalp formula.
The 8% figure describes the product's composition. There is currently no controlled human evidence showing that an 8% topical AHK-Cu serum produces better hair-growth outcomes than a lower percentage.
For research concentrations, topical percentages and dose-related questions, see our AHK-Cu dosage guide.
What the evidence does not establish
This is a cosmetic scalp serum, not an FDA-approved hair-loss treatment.
No controlled human trial has established an optimal topical AHK-Cu percentage, a guaranteed hair-regrowth response or a clinically validated results timeline.
Ingredient research can help explain why AHK-Cu is used in this type of product, but it should not be presented as clinical evidence for this exact finished serum.
K.W.
Verified customer
Before and after photos
Before-and-after photos shared by verified customers of our copper peptide hair serums. Photos are shown as submitted, with the week they were taken.
Customer photos show individual experiences and are not a controlled clinical study.
K.W.
Individual results vary. These are customer experiences, not clinical evidence.
Copper Tripeptide-3
What AHK-Cu is
A short guide to the one active in the bottle.
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01
AHK-Cu is a copper-binding tripeptide: three amino acids, alanine, histidine and lysine, complexed with copper. That copper-peptide complex is what makes the serum blue.
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02
It is a close relative of GHK-Cu, the copper peptide in our face creams and GHK-Cu serum. The two differ by one amino acid, alanine in AHK-Cu and glycine in GHK-Cu. GHK-Cu occurs naturally in the body and is studied mainly on skin; AHK-Cu is made in the lab and studied mainly in hair research.
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03
In the best-known study, AHK-Cu stimulated the elongation of isolated human hair follicles and the growth of dermal papilla cells in the laboratory. That makes it an ingredient of interest for scalp care; it does not show that this serum regrows hair in people.
What goes into the bottle
An 8% copper-peptide formula labeled with 4,800 mg of AHK-Cu per 2 oz (60 mL) bottle. The label lists two ingredients: Distilled Water and AHK-Cu.
COPPER PEPTIDE · 4,800 MG
AHK-Cu
Copper Tripeptide-3
The copper-binding tripeptide that gives the formula its characteristic blue color, and the primary active ingredient in this scalp serum.
The complete label listAll ingredients · as printed on the label
- AHK-Cu
- Distilled Water
As printed on the bottle.
Two listed ingredients
Distilled Water and AHK-Cu. The full label takes seconds to check.
Why the serum is blue
The color comes from the copper-peptide complex itself. Nothing is added simply to make the serum blue.
What to expect with consistent use
AHK-Cu research does not establish a clinical hair-growth timeline, so your own photos are the best guide. Here is how the first weeks usually go, with a few words from customers.
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Day 1
Take a starting photo
Photograph your part or crown in daylight before the first application, and repeat the same photo every four weeks under similar lighting and styling. Gradual changes are hard to judge in a mirror.
“Advice to let it dry before going to bed though.” Anwar A.
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Weeks 1 to 4
First applications
The lightweight feel, the blue color, the drying time and how the serum fits into your routine are among the first things you can assess.
Tip: keep the bottle next to your toothbrush, so morning and evening use becomes a habit.
“It has only been a month and it's too soon to know it's efficacy.” Mayette S.
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Weeks 5 to 8
With consistent use
Keep to the morning-and-evening directions and compare each month's photo with Day 1 rather than judging in the mirror. Experiences vary from person to person.
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Weeks 9 to 12
One bottle, and your photos
Take a week-12 photo and compare it with Day 1 to judge how the serum suits you.
How long one bottle lasts depends on the amount used at each application. Subscribe and Save delivers a bottle every month at 20% off and can be paused at any time.
Quotes come from verified customer reviews and describe individual experiences, not a clinical study. Results vary.
A simple daily scalp routine
Leave-on use on a clean, dry scalp, morning and evening.
01 · Part and apply
02 · 30 to 60 secondsMassage it in
Gently massage for 30 to 60 seconds with clean fingertips or a soft scalp massager to distribute the serum across the area.
03 · Leave onDo not rinse
Let the serum stay on the scalp and dry before layering other products. Repeat in the evening, and let it dry before bed.
Let it dry before fabric
The serum is deeply colored. Let it dry before contact with light-colored bedding, hats or clothing. On white, silver or bleached hair, keep it at the scalp; shampoo washes it out.
Test on a small area first
Test the serum on a small scalp area first if you are sensitive or are introducing several new scalp products at the same time. Stop if irritation persists, and keep it away from the eyes and broken skin. Keep out of reach of children, and ask a healthcare professional before use during pregnancy or breastfeeding.
What you can layer it with
Let the serum dry before adding other products. There is no clinically established universal schedule for combining AHK-Cu with minoxidil, microneedling or other active scalp treatments, so ask your clinician or follow your device instructions on timing.
What the lab reports show, and what research can tell us
Lab reports and published research answer different questions. A lab report documents measurements on a specific sample or production lot. Published research studies AHK-Cu more broadly and does not test this finished serum. We keep the two separate.
Two kinds of evidence
Lab reportMeasures one sample or lot of this finished serum.
Published researchStudies AHK-Cu more broadly, not this serum.
Ex vivoHuman hair follicles
AHK-Cu in ex vivo research
AHK-Cu was tested in isolated human hair follicles and stimulated follicle elongation under laboratory conditions. The study did not test this finished serum on people's scalps or measure clinical hair regrowth.
Read the full AHK-Cu hair research review
Ingredient research · Pyo et al., 2007 · not this finished productIn vitroDermal papilla cells
AHK-Cu in cell research
AHK-Cu increased cultured dermal papilla cell proliferation and changed several apoptosis-related markers. The measured reduction in apoptotic cell count itself was not statistically significant.
Ingredient research · Pyo et al., 2007 · in vitroReviewExperimental evidence
What the research does not yet establish
A 2026 review still describes the AHK-Cu hair evidence as experimental. Human clinical trials are needed to establish hair-growth efficacy, the best topical concentration, delivery to the follicle and a results timeline.
Review · AHK-Cu research generally · not this finished productCertificate of analysis
References · Ingredient research, not studies of this finished serum 2
- Pyo HK, Yoo HG, Won CH, et al. The effect of tripeptide-copper complex on human hair growth in vitro. Arch Pharm Res. 2007;30(7):834-839. doi:10.1007/BF02978833. View study ↗
- Fan C, Chen Y, Huang Q, et al. Overview of Short Peptides for Hair Loss. Biomedicines. 2026;14(4):864. View review ↗
Three copper peptide sprays, side by side
They differ in which copper peptide they carry, how often you use them and how long a bottle lasts. No study has compared them, so pick the one that suits your routine.
GHK-Cu Hair & Scalp Serum
$55 a bottle
$0.92 a day · lasts about 60 days
- AHK-Cu per bottle
- None
- GHK-Cu per bottle
- 2,400 mg
- Daily routine
- Once a day
- Ingredients
- GHK-Cu, distilled water
Suits you if you want a once-daily GHK-Cu mist at the lowest price.
AHK-Cu + GHK-Cu Hair Serum Pro
$185 a bottle
$6.17 a day · lasts about 30 days
- AHK-Cu per bottle
- 2,400 mg
- GHK-Cu per bottle
- 2,400 mg
- Daily routine
- Morning and night
- Ingredients
- AHK-Cu, GHK-Cu, distilled water
Suits you if you want AHK-Cu and GHK-Cu together rather than a single-peptide formula.
This page
AHK-Cu Copper Peptide Hair Serum 4800mg
$229 a bottle
$7.63 a day · lasts about 30 days
- AHK-Cu per bottle
- 4,800 mg
- GHK-Cu per bottle
- None
- Daily routine
- Morning and night
- Ingredients
- AHK-Cu, distilled water
Suits you if you specifically want our highest-concentration pure AHK-Cu leave-on scalp formula.
A subscription, delivered every month. Pause or cancel any time.
30-day money-back guarantee
Bottle life assumes the suggested use and depends on how much you spray.
What customers say
Reviews marked Verified Buyer are from confirmed purchases. Customer reviews describe individual experiences with this product and should not be interpreted as clinical evidence. Every review is shown.
Customers Talked About
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- Application
- Side Effects
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7 reviews
- VHVashti H.Verified BuyerRated 5 out of 5 stars9/10/26Great product
Love this stuff but unfortunately it is too expensive!
- JJasminVerified ReviewerRated 5 out of 5 stars6/27/26Eyebrows
Because everyone takes this for hair growh- i thougt i will test this on my eyebrows.
When i was young i was plucking my eyebrows - thin brows were the ,,it thing"- but then they stopped growing when i was 20 years old...
Now i am 44- and first time since i was young- my eyebrows are growing back fuller and where i plucked them when i was younger.
I am so happy!!
- SFStephen F.Verified BuyerRated 4 out of 5 stars6/10/26Results
Took a couple months, but using this once or twice a week and pairing with GHK CU and a dermastamp, finally seeing results that I never saw with typical minoxidil.
- MSMayette S.Verified BuyerRated 3 out of 5 stars6/7/26Too Soon
It has only been a month and it's too soon to know it's efficacy. There's been no noticeable effects so far.
- AAAnwar A.Verified BuyerRated 4 out of 5 stars5/11/26AHK-Cu Peptide topical Serum
Purchased the AHK-Cu Peptide Serum. Application has been by spray daily; once in the morning and once at night. I also use it with a scalp massage gadget. I don't place as much in the morning since I will be at work and will dry blue (but not stain). Advice to let it dry before going to bed though. Have been using it now for about 2-3 weeks. Still too early to notice difference but will continue for a 90 day period and hopefully have visible results.
- JJeffVerified BuyerRated 5 out of 5 stars1/16/26THE BEST!
I've used many different treatments for thinning hair, I've started using their AHK-Cu peptide, 2400mg, went through 3 bottles and had good results. I'm about halfway through the 4800mg bottle and I'm seeing excellent results! Will continue using!
- HKheather k.Verified BuyerRated 5 out of 5 stars10/14/25satisfied
I am totally satisfied with this product. I think it is easy to apply and has no odor. The dark color will stain your scalp but wipes right off with a damp rag. I am only half way through the bottle so at this point I have not noticed any significant change in the spots I am applying. I will definitely order another bottle as my healthcare worker suggested at least 3 months and I am combining this with other protocol.
Company was easy to work with and arrived on timely manner.
Individual results vary. Customer experiences, not a clinical study.
Questions we hear most often
The product is formulated and labeled with 4,800 mg of AHK-Cu per 2 oz bottle, equivalent to an 8% concentration. That describes the finished formula; it is not a clinically established hair-growth dose.
That has not been established in controlled human research. This is Neurogan Health's highest-concentration pure AHK-Cu scalp serum, but a higher percentage should not automatically be interpreted as better clinical results.
AHK-Cu has experimental research involving isolated human hair follicles and dermal papilla cells, but it has not been shown in a controlled human clinical trial to regrow hair on the scalp.
Apply it to clean, dry scalp, gently massage for 30 to 60 seconds and leave it on. The current product directions call for morning and evening use.
There is no clinically established AHK-Cu results timeline. Published research did not follow people applying this topical serum for a defined number of weeks or months.
The characteristic blue color comes from the copper-peptide complex itself.
The serum is deeply colored. Allow it to dry before contact with light-colored fabrics. Individual application amounts and fabrics vary.
Yes. The two peptides can be formulated together. If you want both in one leave-on serum, see AHK-Cu + GHK-Cu Serum Pro.
There is no clinically established universal AHK-Cu + minoxidil protocol. If you use a drug treatment for hair loss, ask a healthcare professional or pharmacist if you're unsure how another scalp product fits into your routine.
There is no controlled human study establishing the safety or benefit of applying AHK-Cu to freshly microneedled scalp.
A topical product can cause irritation or sensitivity in some users. See our AHK-Cu safety guide for the full evidence review.
No. This is a topical cosmetic hair and scalp serum.
Available reports are linked in the Lab Results section and through Neurogan Health's Lab Results page.
Still have a question?
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4,800 mg of AHK-Cu in distilled water, in a 2 oz (60 mL) bottle.
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