GHK-Cu Dosage Chart: 1.7mg/Day Injectable

GHK-Cu (copper tripeptide-1) is a naturally occurring copper-peptide complex that plays crucial roles in tissue repair, collagen synthesis, and antioxidant enzyme function. Unlike most peptides, GHK-Cu exists naturally in human plasma, urine, and saliva. Topical GHK-Cu has extensive clinical research. Injectable GHK-Cu has no human trials. This is not medical advice.

Research-context information only. GHK-Cu is a research peptide. Protocols, doses, and reactions reported below come from published research and self-reported community sources. This article reports what has been documented, not what should be done. Consult a licensed physician for personal medical decisions.

Quick Reference: Standard Protocol

Topical alternative: 0.1-1% concentration applied daily/nightly on a continuous basis. Topical has clinical trial support; injectable is community-driven.

Cycling: 8 Weeks On, 8 Weeks Off

Community protocols describe 1.7 mg subcutaneous daily in the morning for 8 weeks, then 8 weeks off. GHK-Cu effects on skin and hair build gradually over the cycle. The cycling approach is conservative given the lack of long-term human injectable data.

Morning injection aligns with natural circadian collagen synthesis rhythms. Empty stomach is not required but many users prefer consistent timing. Topical users can apply evening for overnight penetration and repair.

Routes of Administration

Subcutaneous injection (community protocol): Community sources describe the abdomen, love handles, and thighs — areas with subcutaneous fat — as the typical injection sites, at a volume of approximately 0.1 mL using a 29-31 gauge insulin syringe. No human clinical trials for this route exist.

Topical application (well-studied): Serums at 0.1-0.5%, creams at 0.2-1%, hair products at 0.1-0.3%. Apply to clean skin, allow absorption before other products. For hair, massage into scalp. Clinical trial support for skin aging, wound healing, and hair density.

Topical Dosing Protocols

GHK-Cu topical formulations have been studied in clinical trials for over two decades, making this the most evidence-supported delivery route. Concentrations in published research range from 0.05% to 1%, depending on the target tissue and intended outcome.

Concentration Ranges by Use Case

Skin aging and anti-wrinkle protocols: Clinical trials have used 0.05-0.1% GHK-Cu in facial creams and serums. Studies documented improvements in fine lines, skin firmness, and overall clarity at these concentrations over 8-12 week evaluation periods.

Wound healing support: Wound dressing research has employed higher concentrations of 0.2-1% GHK-Cu. Published studies reported accelerated wound closure and improved collagen deposition at these levels (Arul et al., 2005).

Hair and scalp density: Dermal papilla stimulation research has used 0.1-0.3% GHK-Cu in scalp treatments. In vitro studies demonstrated follicle stem cell activation, and limited clinical data reported increased hair density and thickness at 0.2% concentration (Park et al., 2011).

General anti-aging serum: Community and commercial formulations commonly fall in the 0.1-0.5% range, bridging the clinical trial concentrations for skin aging and wound healing applications.

Application Protocol Summary

Topical Application Notes

Absorption timing: Published protocols describe application to clean, dry skin with 10-15 minutes of absorption time before layering other skincare products. Evening application is commonly cited in cosmetic studies to align with overnight tissue repair cycles.

Scalp protocols: Hair-focused formulations are typically massaged into the scalp with focus on areas of thinning. Product formats in this category include dedicated scalp serums, shampoos, and leave-in treatments.

No cycling required: Unlike injectable protocols (8 weeks on / 8 weeks off), topical GHK-Cu does not require cycling. Cosmetic safety data from extended-use studies supports continuous application at the concentrations listed above.

Formulation stability: The copper complex requires proper stabilization -- pH, carrier formulation, and packaging all affect bioactivity. Commercial products formulated with copper tripeptide-1 as the INCI ingredient have generally addressed these stability requirements. DIY formulations from raw powder carry more variability in copper complex integrity.

Topical vs Injectable: Evidence Comparison

The two delivery routes have fundamentally different evidence profiles:

• Topical GHK-Cu has decades of published clinical trial data for skin aging, wound healing, and hair density. It is a recognized cosmetic ingredient (copper tripeptide-1) used in regulated skincare products worldwide.
• Injectable GHK-Cu has no published human clinical trials. Protocols are entirely community-developed, with doses extrapolated from cell culture bioactivity data and molecular weight calculations.

Topical concentrations deliver GHK-Cu directly to skin and follicle targets. Injectable administration is hypothesized to provide systemic distribution, but human pharmacokinetic data for this route does not exist.

For a detailed breakdown of route-specific mechanisms, absorption differences, and use-case matching, see GHK-Cu Topical vs Injectable: Route Comparison.

Reconstitution Quick Reference

Math: 50,000 mcg / 3 mL = 16,667 mcg/mL (16.67 mg/mL). For 1.7 mg: 1,700 / 16,667 = 0.102 mL = ~10 units. One vial lasts ~29 days.

Community protocols describe gentle swirling — not shaking — to avoid degradation, with storage at 2–8°C and use within 28 days. For step-by-step instructions, see the GHK-Cu Reconstitution Guide.

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Where These Numbers Come From

GHK-Cu has extensive topical research but injectable protocols are community-developed.

Topical clinical data: Decades of research on wound healing (0.2-1% GHK-Cu in wound dressings showed accelerated healing and improved collagen deposition), skin aging (facial creams with 0.05-0.1% improved fine lines, firmness, and clarity), and hair growth (0.2% scalp treatments increased density and thickness) (Pickart et al., 2012).

Natural plasma levels: GHK-Cu is community-cited to occur in human plasma at ~200 ng/mL (young adults) declining to ~80 ng/mL (older adults). This decline drives interest in supplementation.

Injectable rationale: Community doses (1-2 mg daily) are derived from bioactive concentrations in cell culture (nanomolar range), molecular weight calculations from topical concentrations, and conservative starting assumptions. No human pharmacokinetic data exists for injectable use.

Gene expression: GHK-Cu affects expression of over 4,000 genes related to tissue repair, antioxidant defense, and inflammation (Campbell et al., 2012).

Stacking Protocols

Stacking tips: Community protocols describe introducing one peptide at a time to assess individual response, using separate injection sites for multiple peptides, and monitoring copper levels where cumulative intake is a concern.

Side Effects & Safety

• Topical: minimal -- occasional mild skin irritation in sensitive individuals; decades of cosmetic use with excellent safety
• Injectable: unknown -- no human clinical safety data for this route
• Injection site redness -- standard for SC peptides, community reports generally well-tolerated
• Copper accumulation (theoretical) -- repeated injections could theoretically raise levels, though doses are small
• Wilson's disease -- individuals with copper metabolism disorders should avoid GHK-Cu
• Iron interaction -- high copper can interfere with iron absorption; monitor if supplementing both
• Baseline copper/ceruloplasmin testing is described in community protocols for long-term injectable use

mg to Units Conversion

On a standard 100-unit insulin syringe, each "unit" equals 0.01 mL (so 100 units = 1 mL). Once GHK-Cu is reconstituted, the conversion from a target dose to syringe units depends on the chosen dilution.

The two reconstitution ratios most often described in community protocols are below.

Reconstitution A: 50 mg vial + 3 mL BAC water (16.67 mg/mL) — the standard dilution from the Quick Reference above.

Reconstitution B: 50 mg vial + 5 mL BAC water (10 mg/mL) — more BAC water for larger, easier-to-measure draws.

These conversions reflect the dilutions documented in community reconstitution protocols. They report how the math is described, not a recommended dosing schedule.