Side-by-side · Research reference

GHK-CuvsMK-677

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

AHuman-MechanisticReviewed8/47 cited

BPhase 2Reviewed13/45 cited

GHK-Cu

Tripeptide · Skin / Hair / Wound Healing

1–2 mgSQ dosePickart 2018

HumanMechanisticPickart 2018 Zink 2003

HoursHalf-life

SQ or topical · Local · Daily or 2-3×/week

MK-677

Oral GHS · Ibutamoren

10–25 mgDaily dose (oral)Nass 2008

Phase 2Evidence levelMurphy 1998 Nass 2008

~24 hrHalf-lifeNass 2008

Oral capsule · 1×/day

01Mechanism of Action

Parameter

GHK-Cu

MK-677

Primary target

Copper-dependent enzymes (lysyl oxidase, SOD); regulator of >4000 human genesPickart 2018

Ghrelin receptor (GHS-R1a)Murphy 1998

Pathway

Cu(II) delivery via GHK chelation → ↑collagen / elastin / GAG synthesis; ↓inflammatory cytokines; ↑hair follicle growth-factor signalingPickart 2018

GHS-R1a → Gαq → Ca²⁺ → sustained GH pulses across 24 hrNass 2008

Downstream effect

Skin firmness + texture improvement, accelerated wound healing, hair regrowth, anti-inflammatory actionPickart 2018 Zink 2003

Sustained GH + IGF-1 elevation; appetite stimulation; lean mass preservationNass 2008

Feedback intact?

Replaces declining endogenous levels

Pulsatile pattern preserved despite long half-lifeMurphy 1998

Origin

Endogenous tripeptide first isolated from human plasma; declines from ~200 ng/mL at age 20 to ~80 ng/mL at age 60Pickart 2018

Non-peptide spiroindane-piperidine small molecule designed at MerckMurphy 1998

Antibody development

—

02Dosage Protocols

Parameter

GHK-Cu

MK-677

Standard SQ dose

1–2 mg / dayPickart 2018

Anecdotal injectable range; topical creams use 0.1–2% solutions.

—

Topical concentration

0.1–2.0% in serum / cream

—

Frequency

Daily or 2–3× per week (SQ)

Once daily, oral

Lower / starter dose

0.5 mg / day SQ

5 mg / day

Evidence basis

Human-mechanistic + topical clinical studiesPickart 2018

Phase 2 trials (Nass 2008, Murphy 1998)Nass 2008 Murphy 1998

Duration

8–12 weeks for visible skin / hair effect

8–16 weeks per cycle (off-cycle to reset receptor sensitivity)

Reconstitution

Bacteriostatic water; light-protected

Oral, no reconstitution

Timing

No specific time; evening preferred for topicals

Pre-sleep preferred for natural GH pulse alignment

Half-life

Hours (estimated; rapid tissue uptake)

~24 hrNass 2008

Once-daily dosing covers 24 hours.

Standard dose

—

10–25 mg / day oralNass 2008

25 mg used in Nass 2008 elderly trial; 10–15 mg common community dose.

04Side Effects & Safety

Parameter

GHK-Cu

MK-677

Injection site reaction

Erythema, mild pruritus (common)

—

Topical irritation

Mild redness, transient stinging

—

Copper accumulation

Theoretical with very high chronic doses

—

Allergic reaction

Rare hypersensitivity to copper

—

Pregnancy / OB

Avoid topical and SQ — insufficient data

Avoid

Wilson disease

Contraindicated

—

Increased appetite

—

Strong appetite increase via ghrelin agonism

Water retention

—

Mild edema, paresthesias

Glucose tolerance

—

↑ HbA1c +0.3–0.5% in 2-yr elderly trialNass 2008

IGF-1 elevation

—

+50–100% sustainedNass 2008

Cancer risk

—

Contraindicated in active malignancy (GH/IGF-1 axis)

Cardiovascular

—

No clear adverse signal in trials; congestive heart failure caution

Drowsiness

—

Common, especially during initial weeks

Absolute Contraindications

GHK-Cu

·Wilson disease (copper-overload disorder)
·Pregnancy / breastfeeding
·Known copper hypersensitivity

MK-677

·Active malignancy
·Pregnancy / breastfeeding
·Disrupted hypothalamic-pituitary axis
·Congestive heart failure (caution)

Relative Contraindications

GHK-Cu

·Hemochromatosis (copper-iron crosstalk theoretical)
·Concurrent copper-chelator therapy

MK-677

·Untreated diabetes
·Pre-diabetes
·Severe insulin resistance

05Administration Protocol

Parameter

GHK-Cu

MK-677

1. Reconstitution

Add 1–2 mL bacteriostatic water to a 50 mg vial → 25–50 mg/mL. Use within 30 days, refrigerated.

Capsule or oral solution. No injection.

2. Injection site

SQ — local to the area of interest (face, scalp) for skin / hair indications. Rotate sites.

Oral. Take with or without food.

3. Timing

Anytime; evening preferred. Topical: apply to clean dry skin.

Pre-sleep preferred — aligns with natural GH pulse.

4. Storage

Lyophilised: room temp, light-protected. Reconstituted: refrigerate, light-protected, ≤30 days.

Capsule: room temp ≤25 °C, dry place.

5. Needle

30–31G, short (4–6 mm) for shallow SQ. Topical: clean fingertips, no needle.

Monitor HbA1c every 8–12 weeks during chronic use.

06Stack Synergy

GHK-Cu

+ BPC-157

Moderate

View BPC-157 →

GHK-Cu drives ECM remodelling and copper-dependent enzymes; BPC-157 upregulates VEGFR2 angiogenesis and fibroblast migration. The pathways are non-overlapping and complementary — together they accelerate wound healing more than either alone in anecdotal protocols.

GHK-Cu: 1–2 mg SQ · daily near wound
BPC-157: 250–500 mcg SQ · daily near wound
Primary benefit: Combined ECM rebuilding + angiogenesis for tissue repair

MK-677

— no documented stacks