Pal-AHK
Palmitoyl Tripeptide-3
Pal-AHK (Palmitoyl Tripeptide-3) is a healing & recovery research compound. Palmitoylated AHK for skin/scalp penetration — collagen and follicle support. It is not a copper peptide: the palmitoyl group occupies the free N-terminal amine AHK uses to anchor copper, so no copper is delivered.
Pal-AHK quick facts
| Reported research dose | Topical, as directed |
| Route | Topical |
| Frequency | 1-2x Daily (topical) |
| Half-life | N/A (topical) |
| Forms | Topical |
| Evidence level | Cosmetic/topical |
Topical, penetrating AHK for skin and hair — a signaling lipopeptide, not the copper-carrying AHK-Cu.
How Pal-AHK works
Palmitoylated AHK for skin/scalp penetration — collagen and follicle support. It is not a copper peptide: the palmitoyl group occupies the free N-terminal amine AHK uses to anchor copper, so no copper is delivered.
Proposed benefits
Hair and scalp support — the palmitoylated AHK tripeptide, which delivers no copper (cosmetic).
Where to get Pal-AHK
See vetted vendors for Pal-AHK →The evidence for Pal-AHK
Graded by what exists behind each claim.
✅ Clinically validated
- No standalone clinical trials. The evidence is the topical cosmeceutical literature on palmitoylated copper-peptide analogs generally, which supports collagen stimulation but does not isolate this molecule — every study tests it inside a formulation with several other actives, so nothing attributes the effect to Pal-AHK specifically.
📊 Correlative data
- Used in cosmetic formulations for skin firmness and in hair serums. Reported experience is difficult to separate from the other actives it is nearly always combined with.
🧪 Theoretical / extrapolated
- AHK with a palmitic acid chain for skin penetration — the same modification logic as Pal-GHK applied to the hair-weighted tripeptide.
- Predicted to stimulate dermal papilla activity and collagen without delivering copper. The rationale is coherent; the specific human evidence for this exact molecule is thinner than the marketing suggests.
How to read these tiers: they say how much human evidence exists, not how well something works — and ✗ flags harm, never a disappointing trial. How the evidence tiers work →
What Pal-AHK actually does
The peptide is Ala-His-Lys. Computed from the sequence it is 354.41 Da, isoelectric point 9.70, net charge about +1.05 at blood pH and +1.92 at skin-surface pH. Palmitoylated it becomes 592.82 Da.
Start with the naming problem, because this card carries one. Ala-His-Lys differs from Gly-His-Lys by a single methyl group — alanine instead of glycine at position 1, 14 Da — and the two are sold for different jobs, hair and skin. But the INCI label attached to this compound is where it gets awkward: the Cosmetic Ingredient Review’s own report on palmitoyl oligopeptides states that palmitoyl tripeptide-3 is listed as a technical name for palmitoyl tripeptide-5 CIR Expert Panel (Cosmetic Ingredient Review) 2012, and palmitoyl tripeptide-5 is defined there as palmitic acid plus a three-residue peptide of lysine and valine. There is no histidine in that molecule at all. So the INCI name commonly attached to palmitoylated AHK points, in the regulatory literature, at a completely different peptide — the one sold elsewhere as a thrombospondin mimic. Anybody buying by INCI number in this corner of the market is not necessarily buying what the marketing describes, and no vendor publishes an amino-acid analysis that would settle it.
The single methyl group is the whole product differentiation, and nobody has ever tested it. Gly to Ala adds one carbon and one stereocentre. It does not change the isoelectric point, the charge, the donor atoms available to a metal, or the number of residues. If that methyl group genuinely redirects a molecule from skin to follicle, it is one of the most specific structure-activity relationships in cosmetic chemistry; if it does not, then two products are being sold for two organs on the strength of 14 Da. No published experiment has put AHK and GHK on the same tissue at the same concentration.
The copper question, and it decides what this molecule can do. The activity AHK is famous for belongs to AHK-Cu, the copper complex. In this class of tripeptide the metal is held by an arrangement of three nitrogens and an oxygen, and the first of those nitrogens is the free alpha-amino group of residue 1 Alshammari 2020. Palmitoylation puts a 16-carbon acyl group on exactly that nitrogen. A palmitoylated AHK therefore cannot present the metal site that the follicle data was generated with. Products in this category are variously described as copper peptides and as copper-free; on the chemistry they cannot be both, and a molecule carrying an N-palmitoyl amide is the second one.
What is left, if the metal site is gone, is a small cationic amphiphile with an imidazole and a lysine — a structure with real affinity for anionic surfaces such as keratin and the sulfated glycosaminoglycans around the follicle, and with no demonstrated receptor. That is a defensible reason to expect it to stay where it is put. It is not a mechanism for making hair grow.
Cell, rodent, human — and where it stops
The one real experiment, and it is better than its reputation. Human hair follicles in organ culture, with AHK-Cu across a range running from 1 picomolar to 1 nanomolar, showed elongation of the follicle; at 1 nanomolar the number of apoptotic dermal papilla cells fell, the Bcl-2/Bax ratio rose, and cleaved caspase-3 and cleaved PARP dropped Pyo 2007. Those are mechanistic read-outs, not a photograph: the claim being made is that the complex holds dermal papilla cells out of programmed cell death, which is a coherent way for a molecule to prolong anagen without being a growth factor. Human tissue, human cells, apoptosis markers in the right direction, and a dose range spanning three orders of magnitude.
Three things that experiment is not. It is the copper complex, not the palmitoylated peptide. It is an explanted follicle bathed directly in medium, with no stratum corneum, no blood supply and no androgen environment. And it is a single paper: no independent group has repeated it in nineteen years, and the recent overview of short peptides for hair loss surveys the field without a controlled human trial to point at for any of them Fan 2026.
Rodents: none. No mouse or rat study of AHK-Cu or of palmitoyl-AHK on hair has been published.
Humans: none for either form. No randomized trial, no vehicle-controlled trial, no published case series with a phototrichogram endpoint. What exists is market presence — palmitoylated tripeptides are documented as common constituents of marketed cosmetic products Resende 2021 — and supplier literature that is not indexed anywhere.
Now the obstacle, and on this page it runs the opposite way to the face peptides, which is the most interesting thing about this compound. The usual objection is size: 592.82 Da is over the 500 Da rule of thumb for stratum corneum Bos 2000, and peptide permeability is the standing problem of the field Mortazavi 2022. But look at what concentration this molecule has to reach. The follicle work was active from 1 nM down to 1 pM Pyo 2007 — a thousand to a million times below the micromolar range that fibroblast collagen work uses. Do the arithmetic. One nanomolar of a 592.82 Da molecule is 0.59 ng/mL. The target is the bulb, so take 100 cm² of scalp by 3 mm of depth, about 30 mL of tissue: reaching 1 nM there needs about 18 ng of peptide delivered. A milliliter of a 0.01% serum contains 1 mg, a million nanograms. That means a delivery efficiency of 0.002% would be sufficient — and for the picomolar end of the active range, a thousandth of that. The barrier arithmetic that sinks the wrinkle peptides does not sink this one, because the concentration requirement is six orders of magnitude smaller.
There is a second reason the scalp is a friendlier target than the cheek: the follicular opening is a shunt around the stratum corneum, and follicles are the one route by which a molecule too large for the intercellular path can reach living tissue. That is standard skin physiology and it is exactly where a hair-directed peptide would want to go. This is extrapolation, and it is labeled as such: no study has measured how much palmitoyl-AHK reaches a human hair bulb. What the calculation establishes is that the usual objection is not the binding one here. The binding obstacle is the other one — that the molecule which reaches the bulb is the copper-free amide, and the only evidence that exists is for the copper complex.
Pal-AHK pharmacokinetics — how much of it actually gets in
What degrades it. Scalp is skin, and skin is proteolytic. N-acylation blocks aminopeptidase attack at the peptide’s front end, which is a measured advantage of palmitoylation in this class Choi 2014, but the His-Lys bond and the C-terminus remain available to endopeptidases and carboxypeptidases. No degradation half-life has been measured for this molecule in skin, scalp or plasma — the figure does not exist in any species.
The barrier, and the route that matters here. 592.82 Da against a 500 Da threshold Bos 2000. But the relevant path for a follicle-directed molecule is not the intercellular lipid route through the stratum corneum; it is the follicular opening, which bypasses it. Massage, a leave-on vehicle and a lipophilic tail all favor that route, and the palmitoyl group is at least as defensible as a way to make a molecule sit in a sebum-filled pore as it is as a way to make it cross a lipid bilayer.
The number that reframes the whole page. A 1 nM target concentration in 30 mL of scalp tissue is about 18 ng of delivered peptide; a 1 pM target is 18 pg Pyo 2007. Against a milligram of peptide in a milliliter of serum, the required efficiency is small enough that the usual complaint about peptide penetration is not the governing constraint. What is unmeasured is not whether enough could get there in principle, but whether any of it does, and in what chemical form.
Copper delivered: zero. An N-palmitoyl tripeptide carries no metal, so serum copper and ceruloplasmin have no mechanism to move on this compound. Where a product genuinely contains AHK-Cu rather than the palmitoylated peptide, the copper load from a topical scalp dose is still micrograms against a daily dietary intake in the low milligrams — three orders of magnitude apart, which is why topical copper peptides do not raise systemic copper.
What would have to be true, and how you would know it was not
What to watch. A fixed-frame photograph of a marked scalp region — same parting, same lighting, same camera height, hair damp and combed the same way — at week 0, week 16 and week 24, plus a hair count in a tattooed or otherwise permanently marked 1 cm² target area. If a trichoscope is available, terminal-to-vellus ratio and hair shaft diameter are the two numbers that separate a real anagen effect from a cosmetic one.
How long before it means anything. Sixteen weeks minimum, twenty-four to be sure. A hair that re-enters anagen still has to grow at about 1 cm a month before anyone can see it, and the proposed mechanism — holding dermal papilla cells out of apoptosis Pyo 2007 — acts on the next cycle, not on the shaft already there.
What will fool you. The shedding rebound. Anyone who starts a scalp routine during or just after a telogen shed will see improvement on the schedule the hair cycle was going to produce anyway, and will attribute it to the bottle. The second trap is the co-formulation: this peptide is almost never sold alone, and minoxidil, caffeine, ketoconazole or a red-clover extract in the same serum will do more than it does.
Prediction 1, and it is the one that cuts against the product. A copper-free palmitoylated AHK will underperform AHK-Cu in a side-by-side follicle organ culture, because every published number for this peptide was generated with the metal on it and the acyl group sits on the metal’s anchoring nitrogen Alshammari 2020. If they perform identically, then the copper was never the active part and the entire copper-peptide framing of this category is wrong — which would be a bigger result than a win.
Prediction 2, testable in a person with a marked scalp. Because the mechanism is anti-apoptotic rather than mitogenic, the first measurable change should be a fall in shed count and in the telogen fraction, before any change in density — count hairs shed on a fixed wash day for four weeks before starting and compare. A product that increases density without ever changing the shed count is not working the way this mechanism says it works.
Prediction 3. Serum copper and ceruloplasmin stay flat. This site has marker pages for both, and they are on this page to be ruled out rather than watched: a topical tripeptide at cosmetic concentrations delivers micrograms of anything, and the palmitoylated form delivers no copper at all.
What nobody has tested yet
1. The methyl-group experiment. AHK and GHK, same concentration, same human follicle organ culture, same elongation and apoptosis read-outs as the original protocol Pyo 2007. One alanine against one glycine. The entire commercial distinction between a hair peptide and a skin peptide rests on it, both peptides cost almost nothing, and it has never been published.
2. The palmitoyl arm of the same experiment. AHK-Cu, free AHK, and palmitoyl-AHK, in the same dish. That single addition would tell you whether the ingredient people actually buy does anything the molecule it is named after does.
3. Nobody has measured follicular delivery for any peptide in this class. Differential tape stripping with cyanoacrylate follicle casts is an established technique for exactly this question, and the arithmetic above says the amount needed at the bulb is in the nanograms. Someone should go and look for it rather than assuming it in either direction.
4. Nobody has checked whether the imidazole still binds anything after acylation. Modified GHK conjugates can retain copper coordination — a biotinylated version does Tosto 2023 — so the assumption that palmitoylation kills the site is a prediction, not a measurement, and a spectroscopic titration would settle it.
5. The anti-inflammatory arm nobody has connected. The closely related tripeptides suppress TNF-alpha-driven interleukin-6 in human dermal fibroblasts Gruchlik 2012, and perifollicular microinflammation is a documented feature of pattern hair loss. Nobody has asked whether the follicle effect and the cytokine effect are the same effect. A single organ-culture experiment measuring IL-6 in the medium alongside follicle elongation would connect two literatures that have never been put in the same room Pickart 2018.
Pal-AHK — its own safety story, not its class's
The class block is written for injectable repair peptides. What belongs on this card instead is narrower and more useful.
The identity risk is the real risk here. The regulatory record maps the INCI name most often used for this ingredient onto a different peptide entirely CIR Expert Panel (Cosmetic Ingredient Review) 2012, vendors describe the same product as both a copper peptide and a copper-free one, and nothing on a certificate of analysis distinguishes them to a buyer. The practical consequence is not toxicity, it is that a person may be running a molecule other than the one whose evidence they read. Ask a vendor whether the material is a copper complex; the answer changes what the product can be expected to do and it changes the vitamin C interaction below.
Vitamin C, and this is where the copper answer matters. If the material is a genuine copper complex, ascorbate reduces copper(II) to copper(I) and the pair generates reactive oxygen species; that reaction is used as an assay in this exact peptide family Tosto 2023. Applying a high-concentration L-ascorbic acid serum in the same layer as a copper peptide is therefore a real chemical interaction, not a generic layering rule, and separating them by time of day costs nothing. If the material is the palmitoylated, copper-free peptide, the interaction disappears. Same bottle name, two different answers.
Scalp-specific, and not shared with the face cards. A lipophilic cationic amphiphile applied daily to a sebum-rich, follicle-dense surface is exactly the profile that can produce follicular occlusion and seborrhoeic irritation in susceptible people. Nobody has studied it for this ingredient, and the honest instruction is to watch for scalp scaling and itch in the first month and to stop if they appear, because an inflamed scalp sheds more hair, which is the outcome the product was bought to prevent.
What zero adverse events means on this card. There has never been a controlled trial of this compound on a human scalp, so there has never been an arm in which an adverse event could have been recorded Fan 2026. That is not a safety finding in either direction. The substitution cost is the one worth weighing: pattern hair loss has treatments with randomized evidence, and months spent on an untested peptide are months of miniaturization that do not reverse.
Sources read for this page
- Pyo HK, Yoo HG, Won CH, Lee SH, Kang YJ, Eun HC, Cho KH, Kim KH. The effect of tripeptide-copper complex on human hair growth in vitro. Arch Pharm Res 2007 · PMID 17703734
- Alshammari N, Platts JA. Theoretical study of copper binding to GHK peptide. Comput Biol Chem 2020 · PMID 32371360
- CIR Expert Panel (Cosmetic Ingredient Review). Safety Assessment of Palmitoyl Oligopeptides as Used in Cosmetics (scientific literature review). Cosmetic Ingredient Review 2012
- Bos JD, Meinardi MM. The 500 Dalton rule for the skin penetration of chemical compounds and drugs. Exp Dermatol 2000 · PMID 10839713
- Mortazavi SM, Moghimi HR. Skin permeability, a dismissed necessity for anti-wrinkle peptide performance. Int J Cosmet Sci 2022 · PMID 35302659
- Choi YL, Park EK, Kim E, Na DH, Shin YH. Dermal Stability and In Vitro Skin Permeation of Collagen Pentapeptides (KTTKS and palmitoyl-KTTKS). Biomol Ther (Seoul) 2014 · PMID 25143811
- Gruchlik A, Jurzak M, Chodurek E, Dzierzewicz Z. Effect of Gly-Gly-His, Gly-His-Lys and their copper complexes on TNF-alpha-dependent IL-6 secretion in normal human dermal fibroblasts. Acta Pol Pharm 2012 · PMID 23285694
- Fan C, Zhang Y, Wang J. Overview of Short Peptides for Hair Loss. Biomedicines 2026 · PMID 42072405
- Pickart L, Margolina A. Regenerative and Protective Actions of the GHK-Cu Peptide in the Light of the New Gene Data. Int J Mol Sci 2018 · PMID 29986520
- Resende DISP, Ferreira MS, Sousa-Lobo JM, Sousa E, Almeida IF. Usage of Synthetic Peptides in Cosmetics for Sensitive Skin. Pharmaceuticals (Basel) 2021 · PMID 34451799
- Tosto R, Bellia F, Pandini G, Naletova I, Attanasio F, Zimbone S, Grasso G. New Biotinylated GHK and Related Copper(II) Complex: Antioxidant and Antiglycant Properties In Vitro against Neurodegenerative Disorders. Molecules 2023 · PMID 37764500
Pal-AHK — safety, predicted from mechanism
Predicted from mechanism, not from a human safety trial. How that reasoning works →
What the mechanism predicts
Derived from the molecule, not a trial.
- Repair peptides work by promoting angiogenesis — new blood vessel growth — plus fibroblast migration and growth-factor signaling. That is what makes them useful, and it is the entire basis of the one theoretical concern worth naming: angiogenesis is also what a tumor needs to grow beyond a few millimetres.
- There is no evidence these compounds cause or accelerate cancer. There is a mechanistic reason not to run a pro-angiogenic agent systemically with an active or recently treated malignancy, and that reasoning stands without a trial.
- The second predicted issue is more mundane and more likely: they can mask a signal. Something that reduces pain and inflammation around an injury lets you load a tissue that has not finished healing.
What has actually been reported
- Very well tolerated in reported use. Injection-site reactions and transient light-headedness are the common complaints.
- Human data is thin — most of the literature is rodent — so 'well tolerated' here means 'no signal has emerged from a lot of informal use', which is weaker than a clean trial and stronger than nothing.
How to reduce the risk
Same mechanism as the prediction.
- Stop when the thing you were treating has resolved. There is no mechanism here that demands a clock, and equally no reason to keep running a pro-angiogenic signal once the job is done.
- Do not let reduced pain set your training load. The tissue heals on its own timeline whether or not you can feel it. Reloading early on the strength of feeling better is the most common way people turn a good result into a re-injury.
- Get the diagnosis before the peptide. These accelerate healing of things that heal. A tear that needs surgical repair does not become a tear that does not, and the delay costs you.
- One injury, one compound, long enough to judge it. Otherwise you learn nothing transferable for next time.
What it does to your bloodwork
A fact about the assay.
- Nothing routine tracks these directly. The endpoint is the injury, which means your own honest assessment of function is the measurement.
Don't run this if
- Active or recently treated malignancy — the angiogenesis reasoning.
- Any undiagnosed lump or lesion. Find out what it is first.
The honest unknown
- Long-term systemic exposure in humans has never been characterized. The use case is naturally self-limiting — you stop when the injury resolves — which is why this matters less here than it would elsewhere.
Not medical advice. If you take prescription medication or have a diagnosed condition, check this with a pharmacist or doctor.
Pal-AHK — interference & stacking
Predicted from mechanism, not from an interaction study. How mechanism-predicted claims are made →
Applied topically, this has no systemic exposure worth speaking of — so there is nothing to interact with anything you take, and no blood marker it could move. That is the honest answer rather than an empty section. The real interactions for a topical are layering ones: what you put on before and after it, and at what pH.
- How to work up to it, and when not to
- When to take it, and why that window
- Fasted or fed, and when in the day
- Coach Cam's personal notes
- Which compounds push the same lever, and why the dose adds up faster than people count
- What blunts it — the stacks that waste your money
- What compounds the risk, so a side effect arrives sooner than any one of them suggests
- Coach Cam's read on running it alongside the rest of your protocol
Everything above is free and stays free. Skool is where it becomes a plan — Pal-AHK in an order, with the rest of what you're running.
Unlock in Skool — $10/mo →Bloodwork to run alongside Pal-AHK
Baseline first, then again at 8–12 weeks.
| Marker | What it’s watching for |
|---|---|
| hs-CRP (High-Sensitivity C-Reactive Protein) | Baseline inflammation — the thing you're claiming to reduce |
| Complete Blood Count (CBC) with Differential | Infection, anemia and platelet count before anything injectable |
| Comprehensive Metabolic Panel (CMP) | Liver and kidney baseline |
| Vitamin D (25-Hydroxy) | Low D slows soft-tissue and bone healing measurably |
The Inflammation Deep Dive panel covers these in one order — 10 markers, $248.35 with the discount applied.
Check results you already have → · All 103 markers A–Z
Pal-AHK — frequently asked questions
What is Pal-AHK?
Pal-AHK (Palmitoyl Tripeptide-3) is a healing & recovery research compound. Palmitoylated AHK for skin/scalp penetration — collagen and follicle support. It is not a copper peptide: the palmitoyl group occupies the free N-terminal amine AHK uses to anchor copper, so no copper is delivered.
Is the full Pal-AHK protocol on this page?
The reported research dose is on this page, along with how Pal-AHK works and the evidence behind it. The protocol — how to work up to it, frequency, cycle length, time off, what not to stack it with and Coach Cam's notes — is inside Skool.
What is the half-life of Pal-AHK?
Pal-AHK has an approximate half-life of N/A (topical), which is part of what determines how often it's dosed.
What's the evidence behind Pal-AHK?
Current evidence level: Cosmetic/topical. Pal-AHK is offered for research purposes only and is not an approved medicine.
What Pal-AHK is used for
Pal-AHK appears under 1 goal in the goal router.
Related Healing & Recovery compounds
Where this goes next
The pages here are the frameworks. The protocols — the dosing, the order to correct things in, the week-by-week schedule and what to retest — are inside Skool.