Side-by-side · Research reference

AHK-CuvsLivagen

Side-by-side comparison across mechanism, dosage, evidence, side effects, administration, and stack synergies. Citations on every claim where available.

AAnimal-MechanisticHUMAN-REVIEWED14/43 cited

BAnimal-StrongHUMAN-REVIEWED20/32 cited

AHK-Cu

Tripeptide-Copper Complex · Cosmetic

10⁻¹² – 10⁻⁹ MActive range (in vitro)Pyo 2007

Dermal papilla cellsPrimary targetPyo 2007

TopicalRoute

Topical · Scalp / Skin

Livagen

Khavinson Bioregulator · Hepatoprotective Tetrapeptide

50%Dipeptidase inhibitionTimofeeva 2005

Oral / SQRoutes tested

LiverTarget tissueKhavinson 2001

Oral or SQ · Tissue-specific to liver

01Mechanism of Action

Parameter

AHK-Cu

Livagen

Primary target

Dermal papilla cells (DPCs) — specialized fibroblasts in hair follicle morphogenesisPyo 2007

Hepatocyte protein synthesis machineryBrodskiĭ 2001

Pathway

AHK-Cu → DPC proliferation → VEGF elevation, TGF-β1 suppression → Angiogenesis, follicle elongationPyo 2007

Tissue-specific bioregulator → Hepatocyte stimulation → Protein synthesis normalizationBrodskiĭ 2001 Khavinson 2001

Downstream effect

Stimulates hair follicle elongation ex vivo, reduces dermal papilla cell apoptosis, elevates Bcl-2/Bax ratio, reduces cleaved caspase-3 and PARPPyo 2007

Age-dependent enzyme normalization, hepatoprotection in fibrosis/hepatitis models, elevated protein synthesis in senescent hepatocytes

Feedback intact?

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Origin

Synthetic tripeptide with Cu²⁺ chelation — alanine substitution variant of GHK-Cu

Directed chemical synthesis from amino acid analysis of liver polypeptide preparations (Ventvil)

Antibody development

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02Dosage Protocols

Parameter

AHK-Cu

Livagen

Effective concentration (in vitro)

10⁻¹² – 10⁻⁹ MPyo 2007

Stimulated human hair follicle elongation ex vivo and DPC proliferation in vitro.

—

Topical formulation

0.001–0.01% (estimated cosmetic range)

No standardized human protocol published — extrapolated from in vitro data.

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Frequency

Once or twice daily (topical application)

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Route

Topical — scalp or dermal application

Oral or subcutaneous

Resists peptidase hydrolysis, enabling oral bioavailability.Timofeeva 2005

Evidence basis

Ex vivo hair follicle / in vitro DPC studiesPyo 2007

Animal models (rats, 1–24 months age); in vitro hepatocyte cultureTimofeeva 2005 Brodskiĭ 2001 Khavinson 2002

Duration

Not established — cosmetic protocols typically 8–12 weeks

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Animal dose (oral)

—

Not specified in abstracts; 2-week administration protocolTimofeeva 2005

Per os administration in rats.

Duration (experimental)

—

2 weeks (enzyme study); up to 24 months (cell culture)Timofeeva 2005 Brodskiĭ 2001

Human data

—

None in provided literature

04Side Effects & Safety

Parameter

AHK-Cu

Livagen

Local irritation

Mild erythema, pruritus at application site (copper peptide class effect)

—

Copper sensitivity

Rare hypersensitivity reaction in copper-sensitive individuals

—

Systemic absorption

Minimal via topical route — systemic copper toxicity unlikely at cosmetic doses

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Data limitations

No published human safety trials — cosmetic use presumed safe per class precedent (GHK-Cu)

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Reported adverse effects

—

None documented in animal studies

Human safety data

—

No human trials in provided literature

Peptide hydrolysis

—

Weakly hydrolyzed; minimal breakdown by intestinal enzymesTimofeeva 2005

Absolute Contraindications

AHK-Cu

·Known copper allergy or Wilson's disease

Livagen

—

Relative Contraindications

AHK-Cu

·Broken or inflamed skin (increased absorption risk)
·Concurrent use of other copper-containing formulations

Livagen

—

05Administration Protocol

Parameter

AHK-Cu

Livagen

1. Topical application

Apply to clean, dry scalp or target dermal area. Typical cosmetic formulations: 0.001–0.01% AHK-Cu in serum or cream base.

Oral administration supported by peptidase resistance. Subcutaneous route used in organotypic culture experiments.Timofeeva 2005 Khavinson 2001

2. Frequency

Once or twice daily. Evening application preferred for overnight contact time.

No specific timing documented. Two-week protocols used in animal models with daily administration.Timofeeva 2005

3. Scalp preparation

For hair growth: apply directly to scalp, massage gently. No need to rinse. Allow absorption for minimum 2–4 hours.

Elderly individuals may exhibit different enzyme normalization patterns than younger cohorts, based on rat age-stratified findings.Timofeeva 2005

4. Storage

Room temperature, protected from light. Copper complexes may degrade in UV exposure.

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5. Duration

Minimum 8–12 weeks to assess efficacy in hair growth applications, per typical cosmetic peptide protocols.

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06Stack Synergy

AHK-Cu

+ GHK-Cu

Moderate

View GHK-Cu →

Both tripeptide-copper complexes share overlapping angiogenic and wound-healing mechanisms (VEGF elevation, TGF-β modulation, fibroblast proliferation). AHK-Cu's alanine substitution may offer distinct receptor affinity or pharmacokinetics. Co-formulation could provide complementary dermal signaling, though no direct synergy studies exist. Often used interchangeably or in alternating protocols.

AHK-Cu: 0.001–0.01% topical · AM
GHK-Cu: 0.001–0.01% topical · PM
Frequency: Daily alternation or combined formulation
Primary benefit: Comprehensive dermal regeneration, angiogenesis, hair follicle support

Livagen

— no documented stacks