Side-by-side · Research reference

AHK-CuvsSemax

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

BHuman-MechanisticAUTO-DRAFTED12/39 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

Semax

Cognitive enhancer · Russian Pharma

200–600 mcg/doseIntranasalKaplan 2017

HumanMechanisticKaplan 2017

~30 minOnset

Intranasal · 2–3×/day during cognitive demand

01Mechanism of Action

Parameter

AHK-Cu

Semax

Primary target

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

BDNF / NGF expression + monoamine modulationKaplan 2017

Pathway

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

↑ BDNF + NGF synthesis + 5-HT modulation → neuroplasticity + anxiolysis + cognitive enhancementKaplan 2017

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

Improved memory + attention; reduced anxiety; neuroprotection in ischemiaKaplan 2017

Feedback intact?

—

Origin

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

Synthetic 7-AA peptide derived from ACTH(4-7) with C-terminal Pro-Gly-Pro stabilising tailKaplan 2017

Antibody development

—

02Dosage Protocols

Parameter

AHK-Cu

Semax

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.

—

Frequency

Once or twice daily (topical application)

2–3× per day during cognitive demand

Route

Topical — scalp or dermal application

—

Evidence basis

Ex vivo hair follicle / in vitro DPC studiesPyo 2007

Human-mechanistic + Russian clinicalKaplan 2017

Duration

Not established — cosmetic protocols typically 8–12 weeks

10–14 day cycles, repeated PRN

Standard dose

—

200–600 mcg / dose intranasalKaplan 2017

Lower / starter dose

—

100 mcg / dose

Reconstitution

—

Pre-formulated nasal spray (commercial); research vial: bacteriostatic water

Timing

—

Morning + early afternoon

Half-life

—

Short plasma; CNS effect lasts ~3–6 hr

04Side Effects & Safety

Parameter

AHK-Cu

Semax

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

—

Data limitations

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

—

Nasal irritation

—

Mild burning or congestion (transient)

Sleep disruption

—

Late-day dosing may interfere with sleep

Headache

—

Uncommon, transient

Long-term safety

—

Limited Western RCT data

Pregnancy / OB

—

Avoid

Absolute Contraindications

AHK-Cu

·Known copper allergy or Wilson's disease

Semax

·Pregnancy / breastfeeding

Relative Contraindications

AHK-Cu

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

Semax

·Active psychiatric instability
·Concurrent strong stimulants

05Administration Protocol

Parameter

AHK-Cu

Semax

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.

Pre-formulated nasal spray (commercial) or research vial reconstituted with bacteriostatic water.

2. Frequency

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

Intranasal — 2–3 sprays per nostril per dose. Tilt head slightly back.

3. Scalp preparation

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

Morning + early afternoon. Avoid evening (sleep disruption).

4. Storage

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

Refrigerate after reconstitution; light-protected.

5. Duration

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

Cycle on/off to avoid neurochemical adaptation.

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

Semax

+ Selank

Moderate

View Selank →

Semax (cognitive enhancer, BDNF/NGF) and Selank (anxiolytic + immune) form the canonical Russian "neuro stack" — both intranasal peptide bioregulators with complementary axes. Semax for cognitive demand; Selank for stress mitigation.

Semax: 200–600 mcg intranasal · morning + afternoon
Selank: 150–300 mcg intranasal · midday + early evening
Primary benefit: Cognitive enhancement + stress mitigation

Kaplan 2017 Zaderej 2014