GHRP-2 Dosing Calculator
GHRP-2 (Pralmorelin): Growth hormone releasing hexapeptide.
Pre-filled with the most-reported community reconstitution protocol for GHRP-2. See how 1 mL and 2 mL of bacteriostatic water change concentration and syringe-draw volume, then adjust the calculator below for your own vial.
Quick answer · Community-reported standard
A 5 mg vial of GHRP-2 reconstituted with 1 mL of bacteriostatic water yields a concentration of 2.50 mg/mL. At that concentration, a 100 mcg dose of GHRP-2 equals 4 units on a U-100 insulin syringe (0.040 mL). GHRP-2 is typically administered once daily via subcutaneous.
GHRP-2 reconstitution: 1 mL vs 2 mL bac water
Bacteriostatic water volume is flexible. Less water means higher concentration and smaller injection volumes; more water means lower concentration and easier dose precision. Both options below are valid for a 5 mg vial.
| BAC water added | Concentration | Volume per 100 mcg dose | Draw on U-100 syringe (units) |
|---|---|---|---|
| 1 mL | 5.00 mg/mL | 0.020 mL | 2 units |
| 2 mL | 2.50 mg/mL | 0.040 mL | 4 units |
Calculate your GHRP-2 dose
Alternative GHRP-2 protocols
Beyond the default above, GHRP-2 is also reported in the following protocols. Use these as starting points and recalculate with the tool above.
GHRP-2 + GHRH Combo Protocol
Community- Dose
- 100 mcg GHRP-2 + 100 mcg Mod GRF 1-29
- Frequency
- 2-3 times daily
- Duration
- 8-16 weeks
- Route
- Subcutaneous
Combined with GHRH analog for synergistic GH release; same saturation dose concept as ipamorelin stacks
Pre-Bed Only Protocol
Community- Dose
- 200 mcg
- Frequency
- Once daily before bed
- Duration
- 8-12 weeks
- Route
- Subcutaneous
Simplified protocol for those who want GH benefits without multiple daily injections
Appetite Stimulation Protocol
Community- Dose
- 100-200 mcg
- Frequency
- 30 minutes before meals, 2-3 times daily
- Duration
- 4-8 weeks
- Route
- Subcutaneous
Leverages GHRP-2 appetite-stimulating properties; used by underweight individuals or those seeking caloric surplus
GH Deficiency Diagnostic (Japan - GHRP Kaken)
Clinical- Dose
- 100 mcg IV bolus
- Frequency
- Single administration
- Duration
- One-time diagnostic test with serial blood sampling over 60-120 minutes
Approved diagnostic protocol in Japan; peak GH response at 15-30 minutes; GH cutoff values define deficiency
GH Provocation Test (Research)
Clinical- Dose
- 1 mcg/kg IV
- Frequency
- Single administration
- Duration
- One-time provocative test with serial sampling
Weight-based dosing used in research settings; produces dose-dependent GH response
GHRP-2 reconstitution & storage
Lyophilized GHRP-2 reconstituted with sterile water or bacteriostatic water for injection. Direct the water along the side of the vial and gently swirl to dissolve; do not shake vigorously. Solution should be clear and colorless.
Lyophilized powder: Store at -20°C to 4°C protected from light and moisture. Reconstituted solution: Refrigerate at 2-8°C, use within 2-4 weeks with bacteriostatic water or promptly with sterile water.
GHRP-2 dosing FAQ
How much bacteriostatic water should I add to a 5 mg vial of GHRP-2?
The community standard is 1 mL of bacteriostatic water for a 5 mg GHRP-2 vial. That gives a concentration of 2.50 mg/mL, so a 100 mcg dose is 4 units on a U-100 insulin syringe. Adding 1 mL instead doubles the concentration to 5.00 mg/mL and halves the draw to 2 units. Less water = smaller injection volume but harder to measure precisely.
How many syringe units is a 100 mcg dose of GHRP-2?
On a standard U-100 insulin syringe, a 100 mcg dose of GHRP-2 is 4 units when the 5 mg vial is reconstituted with 1 mL of bacteriostatic water (2.50 mg/mL). If you use 1 mL of bac water instead, draw 2 units (5.00 mg/mL).
What is the standard GHRP-2 dose?
Community-reported protocols for GHRP-2 typically use 100 mcg–200 mcg once daily via Subcutaneous. 100 mcg is a common starting dose. Injected on empty stomach; fasting 1-2 hours before and 30-60 minutes after. Most common with GHRH analog.
How long does a vial of GHRP-2 last at 100 mcg once daily?
A 5 mg vial of GHRP-2 contains roughly 50 doses at 100 mcg per injection. At once daily dosing, that is approximately 50 days (about 7 weeks) of supply per vial. Reconstituted GHRP-2 should generally be used within 28 days when refrigerated.
Where do you inject GHRP-2?
GHRP-2 is typically injected subcutaneous. Common sites reported in the literature and by users include: Intravenous (antecubital vein) - diagnostic use, Subcutaneous (abdomen) - research use, Subcutaneous (thigh) - research use. Rotate sites with each injection to reduce localized irritation.
Can I use sterile water instead of bacteriostatic water for GHRP-2?
Bacteriostatic water (containing 0.9% benzyl alcohol as a preservative) is strongly preferred for multi-dose vials like GHRP-2 because it inhibits microbial growth and lets a single vial be used over multiple weeks. Sterile water has no preservative and should generally be reserved for single-use preparations only.
More on GHRP-2
GHRP-2 overview
Mechanism of action, primary uses, and research summary
GHRP-2 dosing protocols
Full clinical and research-based dosing reference
GHRP-2 community protocols
Real-world usage patterns from peptide communities
GHRP-2 side effects
Reported adverse effects and safety considerations
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Medical Disclaimer
This website is for educational and informational purposes only. The information provided is not intended to diagnose, treat, cure, or prevent any disease. Always consult with a qualified healthcare professional before using any peptide or supplement.