GHK-Cu Dosage Guide
Written by Alejandro Reyes
Founder & Lead Researcher
Reviewed by Peptide Nerds Editorial · Updated April 2026
Dosage overview
| Typical dose | 1-3% topical (serum or cream); 200 mcg daily subcutaneous (injectable) |
| Frequency | Topical: once or twice daily. Injectable: once daily, 5 days on / 2 days off |
| Cycle length | Topical: continuous use. Injectable: 30-day cycles with breaks |
Dosing notes
Topical application is the most common and best-studied delivery route. Start at 0.5-1% concentration for sensitive skin and gradually increase to 2-3% over several weeks to minimize the risk of the "copper uglies." Apply after cleansing and toning, before heavier moisturizers. Serum formulations absorb faster than creams. Do not layer with vitamin C (L-ascorbic acid) — space applications by at least 12 hours or use on alternating days. Retinol can be used in the same routine but should be separated by 30 minutes or used at different times of day. For microneedling protocols, studies show microneedle-treated skin absorbs significantly more peptide than intact skin — apply GHK-Cu serum immediately after treatment while micro-channels remain open. Injectable GHK-Cu requires reconstitution with bacteriostatic water. Research protocols have used doses ranging from 200 mcg to 2 mg daily. Store reconstituted peptide refrigerated at 2-8 degrees C and use within 30 days. Oral and sublingual formulations exist through some compounding pharmacies but have limited bioavailability data.
Important safety information
Dosage ranges listed above are based on published clinical trial protocols. Individual dosing should be determined by a qualified healthcare provider based on your specific health profile, goals, and response to treatment.
- Start at the lowest effective dose and titrate up gradually
- Monitor for side effects, especially during dose increases
- Do not exceed researched dose ranges without medical supervision
- This is a research compound — human dosing guidelines are not FDA-established
Interactive protocol guide
Step-by-step: your dosing schedule with exact syringe units, what supplies to buy, how to mix, and how to inject.
GHK-Cu Protocol Overview
Goal
Skin/anti-aging
Duration
12 weeks
Route
subcutaneous
Important before you start:
- GHK-Cu is a research peptide. No FDA approval for injectable use.
- Topical GHK-Cu is available and may be preferred for purely cosmetic goals.
- Some users report mild irritation or bruising at the injection site.
Your dosing schedule
Based on a 5 mg vial mixed with 2.5 mL bacteriostatic water (2.00 mg/mL concentration). Using a U-30 insulin syringe.
Draw to here
15 units
on 30-unit syringe
1-12: 1 mg
| When | Dose | Syringe units | Frequency | What to expect |
|---|---|---|---|---|
| 1-12 | 1 mg | 15 units | Once daily | Flat dose. Rotate injection sites to avoid skin irritation. |
1-12: 1 mg
Flat dose. Rotate injection sites to avoid skin irritation.
What you need for a 12-week GHK-Cu protocol
GHK-Cu vials (5 mg each)
Quantity: 17
Bacteriostatic water (30 mL vial)
Quantity: 2
Insulin syringes (U-30, 29ga)
Quantity: 84+ (one per injection, never reuse)
Alcohol prep pads
Quantity: 168+ (one for vial, one for skin)
Sharps container
Quantity: 1
Quantities based on 12-week protocol using 5 mg vials reconstituted with 2.5 mL BAC water each.
How to mix your GHK-Cu
Your concentration:
5 mg peptide + 2.5 mL water = 2.00 mg/mL (2000 mcg/mL)
- 1
Wash your hands
Wash with soap and water for 30 seconds. Dry completely.
- 2
Clean the vial tops
Wipe the rubber stopper on your GHK-Cu vial AND your bacteriostatic water vial with an alcohol swab. Let air dry for 10 seconds.
- 3
Draw 2.5 mL of bacteriostatic water
Using an insulin syringe, draw 2.5 mL (75 units on a U-30 syringe) of bacteriostatic water.
- 4
Inject water into the GHK-Cu vial
Hold the peptide vial at a 45-degree angle. Point the needle at the WALL of the vial, NOT directly onto the powder. Push the plunger slowly over 10-15 seconds. Let the water run down the inside wall.
- 5
Swirl gently to dissolve
Swirl the vial in a slow circular motion for 30-60 seconds. NEVER shake. If not fully dissolved, let it sit for 2-5 minutes and swirl again.
- 6
Refrigerate immediately
Store reconstituted peptide at 36-46 degrees F (2-8 degrees C). Good for 4-6 weeks refrigerated. Label the vial with the date you mixed it.
Common mistakes that ruin your peptide:
- Shaking the vial (breaks peptide bonds, reduces potency 30-50%)
- Spraying water directly on the powder (damages the peptide)
- Using sterile water instead of bacteriostatic water (no preservative, short shelf life)
- Leaving mixed peptide at room temperature (loses 10-20% potency per day)
How to inject GHK-Cu
Timing: Morning or evening, no food restriction
- 1Choose your injection site and rotate each time (at least 1 inch from the last site).
- 2Wipe the injection site with an alcohol prep pad. Let air dry completely.
- 3Draw your dose (check the dosing schedule above for exact syringe units).
- 4Pinch a fold of skin at the injection site.
- 5Insert the needle at a 45-90 degree angle into the pinched skin fold.
- 6Push the plunger slowly and steadily.
- 7Release the skin fold, then withdraw the needle.
- 8Do NOT rub the injection site. Light pressure with a cotton ball is fine if there is any blood.
- 9Dispose of the syringe immediately in your sharps container. Never recap or reuse.
Site rotation tip
Divide your preferred injection area into a mental grid. Move to a new spot each injection. For Abdomen and Thigh and Upper arm injections, alternate between sides (left/right) each time.
Research references
- GHK Peptide as a Natural Modulator of Multiple Cellular Pathways in Skin Regeneration — BioMed Research International (2015) [PubMed]
- GHK and DNA: Resetting the Human Genome to Health — BioMed Research International (2014) [PubMed]
- The Effect of the Human Peptide GHK on Gene Expression Relevant to Nervous System Function and Cognitive Decline — Brain Sciences (2017) [PubMed]
- Stimulation of collagen synthesis in fibroblast cultures by the tripeptide-copper complex glycyl-L-histidyl-L-lysine-Cu2+ — FEBS Letters (1988) [PubMed]
- Synergy of GHK-Cu and hyaluronic acid on collagen IV upregulation via fibroblast and ex-vivo skin tests — Journal of Cosmetic Dermatology (2023) [PubMed]
- The potential of GHK as an anti-aging peptide — Aging Pathobiology and Therapeutics (2020) [PubMed]
- Regenerative and Protective Actions of the GHK-Cu Peptide in the Light of the New Gene Data — International Journal of Molecular Sciences (2018) [PubMed]
- GHK-Cu-liposomes accelerate scald wound healing in mice by promoting cell proliferation and angiogenesis — Wound Repair and Regeneration (2017) [PubMed]
- A gene expression signature of emphysema-related lung destruction and its reversal by the tripeptide GHK — Genome Medicine (2012) [PubMed]
- GHK Peptide Inhibits Bleomycin-Induced Pulmonary Fibrosis in Mice by Suppressing TGFbeta1/Smad-Mediated Epithelial-to-Mesenchymal Transition — Frontiers in Pharmacology (2017) [PubMed]
- The tri-peptide GHK-Cu complex ameliorates lipopolysaccharide-induced acute lung injury in mice — Oncotarget (2016) [PubMed]
- Protective effects of GHK-Cu in bleomycin-induced pulmonary fibrosis via anti-oxidative stress and anti-inflammation pathways — Life Sciences (2020) [PubMed]
- A metastasis-prone signature for early-stage mismatch-repair proficient sporadic colorectal cancer patients and its implications for possible therapeutics — Clinical and Experimental Metastasis (2010) [PubMed]
- Exploring the beneficial effects of GHK-Cu on an experimental model of colitis and the underlying mechanisms — Frontiers in Pharmacology (2025) [PubMed]
- The effect of tripeptide-copper complex on human hair growth in vitro — Archives of Pharmacal Research (2007) [PubMed]
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