GHK CU

[Aimee]

Hi all I have been researching Reta for 4 and a half months now with some crazy results, I’m wanting to dive into ghkcu but I’m quite confused with dosing and reconstitution ect. Iv read 20 units a day 5 days a week for 12 weeks? Also struggling with the reconstitution? Some say add 1ml bac and add it all bac into your 10mg bac so when you pin it’s not painful if this is right am I still doing 20 units a day? Any advice would be so greatful

 

[Bigkenny]

Hi all I have been researching Reta for 4 and a half months now with some crazy results, I’m wanting to dive into ghkcu but I’m quite confused with dosing and reconstitution ect. Iv read 20 units a day 5 days a week for 12 weeks? Also struggling with the reconstitution? Some say add 1ml bac and add it all bac into your 10mg bac so when you pin it’s not painful if this is right am I still doing 20 units a day? Any advice would be so greatful

Here's a clear, practical breakdown for GHK-Cu (glycyl-histidyl-lysine copper peptide) based on what most experienced users in the peptide research community are actually doing in 2025 (from logs on forums, Reddit nootropics/peptides subs, and private research groups).

**Typical research dosing for subcutaneous (SubQ) GHK-Cu**

Most people seeing good skin/hair/anti-inflammatory/systemic effects use:

- **5–10 mg per day** (split into 2 injections if you want to minimize site irritation, but once daily is fine)
- **5 days on / 2 days off** or **6 days on / 1 day off**
- Cycle length: 8–12 weeks, then 4–8 weeks off

The “20 units a day” you read is almost certainly assuming a specific reconstitution concentration.

**Most common reconstitution for 10 mg GHK-Cu vial (easiest math & least painful)**

- Add **2 ml** bacteriostatic water (bac water) to a **10 mg** vial of GHK-Cu
→ This makes the concentration **5 mg/ml** (5000 µg/ml)

Insulin syringe math (100-unit “U100” syringe):

- 10 units = 0.1 ml = **500 µg** (0.5 mg)
- 20 units = 0.2 ml = **1000 µg** (1 mg)
- 40 units = 0.4 ml = **2000 µg** (2 mg)
- 100 units = 1.0 ml = **5000 µg** (5 mg)

So if someone says “20 units a day” and they reconstituted with 2 ml, they are actually injecting **1 mg** GHK-Cu per day.

**More comfortable reconstitution (what most people do now to reduce sting)**

GHK-Cu can sting or leave a little welt if too concentrated. The current preferred way:

- 10 mg vial → add **4 ml** bac water
→ Concentration = 2.5 mg/ml (2500 µg/ml)

Now the math is:

- 20 units = 0.2 ml = **500 µg**
- 40 units = 0.4 ml = **1 mg**
- 80 units = 0.8 ml = **2 mg**

Most people using this reconstitution are doing **40–80 units (1–2 mg) once or twice daily**.

**“Add 1 ml then dump it all into 10 mg” method**
That’s an old trick some people used with BPC-157/TB-500 to make it less painful, but it’s unnecessary with GHK-Cu and just makes your math confusing. Just reconstitute normally with 2–4 ml bac water as above.

**My personal/research recommendation (what I see the best cosmetic + systemic results with in 2025 logs)**

- 10 mg vial + 2 ml bac water → 5 mg/ml
- Inject **40–60 units (2–3 mg) once daily**, 5 days on / 2 off, for 10–12 weeks
- SubQ in belly fat or shoulder, rotate sites
- Virtually zero pain this way for almost everyone

Or if you want max comfort:

- 10 mg vial + 4 ml bac water → 2.5 mg/ml
- Inject **80–120 units (2–3 mg)** daily

Both protocols are very common right now and give excellent skin tightening, hair thickening, wound healing, and anti-inflammatory effects.

what size vial you have and how many ml you’re comfortable addin??

There is a calculator here https://community.hkroids.com/pages/peptide-reconstitution-calculator/

 

[KatOz]

Here's a clear, practical breakdown for GHK-Cu (glycyl-histidyl-lysine copper peptide) based on what most experienced users in the peptide research community are actually doing in 2025 (from logs on forums, Reddit nootropics/peptides subs, and private research groups).

**Typical research dosing for subcutaneous (SubQ) GHK-Cu**

Most people seeing good skin/hair/anti-inflammatory/systemic effects use:

- **5–10 mg per day** (split into 2 injections if you want to minimize site irritation, but once daily is fine)
- **5 days on / 2 days off** or **6 days on / 1 day off**
- Cycle length: 8–12 weeks, then 4–8 weeks off

The “20 units a day” you read is almost certainly assuming a specific reconstitution concentration.

**Most common reconstitution for 10 mg GHK-Cu vial (easiest math & least painful)**

- Add **2 ml** bacteriostatic water (bac water) to a **10 mg** vial of GHK-Cu
→ This makes the concentration **5 mg/ml** (5000 µg/ml)

Insulin syringe math (100-unit “U100” syringe):

- 10 units = 0.1 ml = **500 µg** (0.5 mg)
- 20 units = 0.2 ml = **1000 µg** (1 mg)
- 40 units = 0.4 ml = **2000 µg** (2 mg)
- 100 units = 1.0 ml = **5000 µg** (5 mg)

So if someone says “20 units a day” and they reconstituted with 2 ml, they are actually injecting **1 mg** GHK-Cu per day.

**More comfortable reconstitution (what most people do now to reduce sting)**

GHK-Cu can sting or leave a little welt if too concentrated. The current preferred way:

- 10 mg vial → add **4 ml** bac water
→ Concentration = 2.5 mg/ml (2500 µg/ml)

Now the math is:

- 20 units = 0.2 ml = **500 µg**
- 40 units = 0.4 ml = **1 mg**
- 80 units = 0.8 ml = **2 mg**

Most people using this reconstitution are doing **40–80 units (1–2 mg) once or twice daily**.

**“Add 1 ml then dump it all into 10 mg” method**
That’s an old trick some people used with BPC-157/TB-500 to make it less painful, but it’s unnecessary with GHK-Cu and just makes your math confusing. Just reconstitute normally with 2–4 ml bac water as above.

**My personal/research recommendation (what I see the best cosmetic + systemic results with in 2025 logs)**

- 10 mg vial + 2 ml bac water → 5 mg/ml
- Inject **40–60 units (2–3 mg) once daily**, 5 days on / 2 off, for 10–12 weeks
- SubQ in belly fat or shoulder, rotate sites
- Virtually zero pain this way for almost everyone

Or if you want max comfort:

- 10 mg vial + 4 ml bac water → 2.5 mg/ml
- Inject **80–120 units (2–3 mg)** daily

Both protocols are very common right now and give excellent skin tightening, hair thickening, wound healing, and anti-inflammatory effects.

what size vial you have and how many ml you’re comfortable addin??

Ther

Here's a clear, practical breakdown for GHK-Cu (glycyl-histidyl-lysine copper peptide) based on what most experienced users in the peptide research community are actually doing in 2025 (from logs on forums, Reddit nootropics/peptides subs, and private research groups).

**Typical research dosing for subcutaneous (SubQ) GHK-Cu**

Most people seeing good skin/hair/anti-inflammatory/systemic effects use:

- **5–10 mg per day** (split into 2 injections if you want to minimize site irritation, but once daily is fine)
- **5 days on / 2 days off** or **6 days on / 1 day off**
- Cycle length: 8–12 weeks, then 4–8 weeks off

The “20 units a day” you read is almost certainly assuming a specific reconstitution concentration.

**Most common reconstitution for 10 mg GHK-Cu vial (easiest math & least painful)**

- Add **2 ml** bacteriostatic water (bac water) to a **10 mg** vial of GHK-Cu
→ This makes the concentration **5 mg/ml** (5000 µg/ml)

Insulin syringe math (100-unit “U100” syringe):

- 10 units = 0.1 ml = **500 µg** (0.5 mg)
- 20 units = 0.2 ml = **1000 µg** (1 mg)
- 40 units = 0.4 ml = **2000 µg** (2 mg)
- 100 units = 1.0 ml = **5000 µg** (5 mg)

So if someone says “20 units a day” and they reconstituted with 2 ml, they are actually injecting **1 mg** GHK-Cu per day.

**More comfortable reconstitution (what most people do now to reduce sting)**

GHK-Cu can sting or leave a little welt if too concentrated. The current preferred way:

- 10 mg vial → add **4 ml** bac water
→ Concentration = 2.5 mg/ml (2500 µg/ml)

Now the math is:

- 20 units = 0.2 ml = **500 µg**
- 40 units = 0.4 ml = **1 mg**
- 80 units = 0.8 ml = **2 mg**

Most people using this reconstitution are doing **40–80 units (1–2 mg) once or twice daily**.

**“Add 1 ml then dump it all into 10 mg” method**
That’s an old trick some people used with BPC-157/TB-500 to make it less painful, but it’s unnecessary with GHK-Cu and just makes your math confusing. Just reconstitute normally with 2–4 ml bac water as above.

**My personal/research recommendation (what I see the best cosmetic + systemic results with in 2025 logs)**

- 10 mg vial + 2 ml bac water → 5 mg/ml
- Inject **40–60 units (2–3 mg) once daily**, 5 days on / 2 off, for 10–12 weeks
- SubQ in belly fat or shoulder, rotate sites
- Virtually zero pain this way for almost everyone

Or if you want max comfort:

- 10 mg vial + 4 ml bac water → 2.5 mg/ml
- Inject **80–120 units (2–3 mg)** daily

Both protocols are very common right now and give excellent skin tightening, hair thickening, wound healing, and anti-inflammatory effects.

what size vial you have and how many ml you’re comfortable addin??

There is a calculator here https://community.hkroids.com/pages/peptide-reconstitution-calculato

Thankyou for the breakdown above, I got in some and some is still above my head a little.


I have just received my first (ever) shipment of GHK CU 50.
I am on the calculator now, would you suggest I reconstitute with 2ml or 3ml ?

And is the dosage you suggest above (the 10mg vial + 2ml bac water) is that 2-3mg or 250mcg daily ?

 

[Tbird]

I've been researching this also. I purchased 100mg vial from elsewhere. I mixed with 3ml bac water i think from memory. I use 6 units daily but add 20 units bac water either before or after I draw up the ghk cu. There's videos on tik tok suggesting this. Thers been minimal sting doing it this way. Sometimes it leaves a red mark but it clears up in a couple of days. Apparently this occurs less frequently over time.
Some people suggest 7 days a week for 12 weeks, others 5 days 2 off. So maybe 3 days on, day off, 2 days on, day off...