Key Takeaways
- Injectable GHK-Cu: 1–2mg per injection, once or twice daily
- Topical GHK-Cu cream/serum: 2–4% concentration, once or twice daily
- Cycle length: 8–12 weeks on, 4 weeks off
- 100mg vial at 2mg/day = 50 days of use
- Results start showing at weeks 3–4, significant at weeks 6–8
- Most popular setup: 100mg vial + 2mL BAC water = 50mg/mL concentration
- Free calculator: Reconstitution Calculator →
The standard injectable GHK-Cu dose is 1–2mg per day, subcutaneously. Most people start at 1mg and increase to 2mg after week 1–2. For topical use, standard concentration is 2–4% applied once or twice daily. Full protocol below.
GHK-Cu Injectable Dosage
When reconstituting a 100mg vial, the amount of BAC water you add determines your concentration and how many units you draw per dose. The table below covers the most common setups:
| BAC Water | Concentration | 0.5mg dose | 1mg dose | 2mg dose |
|---|---|---|---|---|
| 1mL | 100mg/mL | 5 IU | 10 IU | 20 IU |
| 2mL ⭐ | 50mg/mL | 10 IU | 20 IU | 40 IU |
| 3mL | 33mg/mL | 15 IU | 30 IU | 60 IU |
| 4mL | 25mg/mL | 20 IU | 40 IU | 80 IU |
The 2mL setup (50mg/mL) is the most popular — easy math, manageable injection volumes, and fits well with standard insulin syringes.
Protocol 1 — Skin & Anti-Aging
- Dose: 1–2mg per injection
- Frequency: Once daily (morning preferred)
- Duration: 8–12 weeks
- Best for: Collagen production, skin elasticity, anti-aging
- Expected results: Visible at weeks 4–6
Protocol 2 — Wound Healing & Recovery
- Dose: 2mg per injection
- Frequency: Twice daily (morning + evening)
- Duration: 4–8 weeks or until healed
- Best for: Post-procedure recovery, chronic wounds, inflammation
Protocol 3 — Hair Growth
- Dose: 1mg injectable daily + topical GHK-Cu on scalp
- Frequency: Daily
- Duration: 12–16 weeks minimum (hair cycles are slow)
- Note: Don't expect visible results before week 8 — hair follicle turnover takes time
Protocol 4 — Maintenance After Cycle
- Dose: 1mg every other day or 3x per week
- Use this: After completing an 8–12 week cycle
- Why: Maintains benefits while allowing receptor sensitivity to reset
How long does a 100mg vial last? It depends on your dose and frequency:
| Dose | Frequency | 100mg Vial Lasts |
|---|---|---|
| 0.5mg | Daily | 200 days |
| 1mg | Daily | 100 days |
| 2mg | Daily | 50 days |
| 2mg | Twice daily | 25 days |
GHK-Cu Topical Dosage
Most commercial GHK-Cu serums come in the 2–4% concentration range — that's the target. Higher isn't better; what matters is getting it on consistently.
- Standard concentration: 2–4%
- Application amount: 3–6 drops per area, fingertip application
- Frequency: Once or twice daily — morning and/or evening
- Timing: After cleansing, before moisturizer
Amount by area:
- Face: 3–5 drops
- Neck/décolletage: 5–8 drops
- Scalp (hair growth): 8–10 drops massaged in, leave on
Injectable vs topical — which one do you actually need?
| Injectable | Topical | |
|---|---|---|
| Bioavailability | Systemic — whole body | Surface — targeted area only |
| Best for | Collagen remodeling, wound healing, hair (systemic) | Surface skin texture, fine lines, targeted areas |
| Results timeline | 3–4 weeks | 4–6 weeks |
| Cost per month | $20–40 (1mg/day from 100mg vial) | $30–80 (depends on product) |
| Convenience | Requires injection | Easy — apply like a serum |
Cycle Length & When to Take a Break
Standard cycle: 8–12 weeks on, 4 weeks off.
Why cycle at all? GHK-Cu receptor sensitivity may gradually reduce with continuous use. A 4-week break resets this. After the break, restart at your starting dose — you don't need to ramp up as slowly as the first time.
Some people run longer cycles (16–20 weeks) without issues. It's not dangerous, it's precautionary. If you're using the KLOW blend (GHK-Cu + BPC-157 + TB-500 + KPV), follow the same 8–12 week cycle.
GHK-Cu Dosage by Goal
| Goal | Protocol | Dose | Duration |
|---|---|---|---|
| General skin anti-aging | Protocol 1 | 1–2mg/day | 8–12 weeks |
| Post-procedure skin recovery | Protocol 2 | 2mg 2x/day | 4–6 weeks |
| Hair growth | Protocol 3 | 1mg/day + topical | 12–16 weeks |
| Wound healing | Protocol 2 | 2mg 2x/day | Until healed |
| Maintenance | Protocol 4 | 1mg 3x/week | Ongoing |
What Affects Your Results
- Quality of GHK-Cu — purity matters. Use vendors with third-party COA (≥98% purity). Lower purity = weaker effect and more unknowns.
- Consistency — GHK-Cu works through cumulative collagen remodeling. Missing doses disrupts the process. Daily is better than sporadic.
- Topical vs injectable synergy — combining both (injectable systemically, topical on target area) produces better results than either alone. More signal to the tissue.
- Diet — adequate protein intake supports the collagen synthesis that GHK-Cu stimulates. Skimping on protein limits how much you get out of the peptide.
- Starting point — people with more visible aging or skin damage often see faster apparent results. Not because GHK-Cu works harder, but because there's more room for visible improvement.
Frequently Asked Questions
What is the standard GHK-Cu dose?
1–2mg per injection, once daily for skin and anti-aging. 2mg twice daily for wound healing or post-procedure recovery. Start at 1mg if you're new to it.
How much BAC water do I add to a 100mg GHK-Cu vial?
2mL is the standard recommended amount, giving you 50mg/mL concentration. At this concentration, a 1mg dose = 20 IU on a U-100 insulin syringe. Simple and accurate.
How long does a 100mg vial last at standard dosing?
At 1mg per day: 100 days. At 2mg per day: 50 days. At 2mg twice daily: 25 days. The vial stores well refrigerated after reconstitution — most people use it well within the 4-week window at higher doses.
Is a higher dose better?
Not necessarily. 1–2mg/day covers the physiological range. There's no evidence that 5mg+ provides proportionally better results, and higher doses increase cost without clear benefit. Stick to the effective range.
Can I use GHK-Cu every day without cycling?
You can — it's not harmful. Cycling is precautionary to maintain receptor sensitivity. Most people run 8–12 weeks on, 4 off. If you want to run longer, that's a personal choice, not a medical risk at standard doses.
What dose for hair growth?
1mg daily injectable is the most commonly used approach. Combine with topical GHK-Cu serum on the scalp for best results. Hair cycles are slow — allow 12–16 weeks minimum before evaluating. Don't cut the protocol short.
Can I combine GHK-Cu with other peptides?
Yes. KLOW blend combines GHK-Cu with BPC-157, TB-500, and KPV in one vial — the most popular combination for skin, healing, and recovery. GHK-Cu also stacks well with CJC-1295/Ipamorelin (GH peptides) and retatrutide for a broader anti-aging protocol.
The information in this article is for educational purposes only and does not constitute medical advice. Always consult a healthcare professional before starting any new supplement or compound. Results vary by individual.