What is GHRP-2?
GHRP-2 (Growth Hormone Releasing Peptide-2), also known as Pralmorelin, is a synthetic hexapeptide that stimulates growth hormone release by binding to the ghrelin receptor (GHS-R1a). It’s one of the most potent GHRPs available, producing strong GH release.
GHRP-2 not only stimulates GH release but also mildly increases appetite, cortisol, and prolactin — though to a lesser extent than GHRP-6. It’s considered a middle-ground option between the appetite-stimulating GHRP-6 and the “cleaner” Ipamorelin.
The 5mg vial provides multiple weeks of research depending on dosing protocol.
Quick Reference
| Parameter | Value |
|---|---|
| Peptide Amount | 5mg |
| Recommended BAC Water | 2mL |
| Resulting Concentration | 2.5mg/mL (2500mcg/mL) |
| Typical Research Dose | 100-300mcg |
| Frequency | 2-3x daily |
| Research Duration | 8-12 weeks |
GHRP Comparison
| Peptide | GH Release | Appetite | Cortisol | Prolactin |
|---|---|---|---|---|
| GHRP-2 | ++++ | + | + | + |
| GHRP-6 | +++ | +++ | + | + |
| Ipamorelin | +++ | Minimal | Minimal | Minimal |
| Hexarelin | +++++ | + | ++ | ++ |
Reconstitution Guide
Materials Needed
- GHRP-2 5mg lyophilized vial
- Bacteriostatic water (BAC water)
- Insulin syringes (U-100, 29-31 gauge)
- Alcohol swabs
- Sharps container
Step-by-Step Instructions
-
Prepare your workspace — Clean area, wash hands thoroughly.
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Clean the vial stoppers — Wipe both vials with alcohol swabs.
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Draw the BAC water — Draw 2mL of bacteriostatic water.
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Add water to peptide vial — Inject slowly down the inside wall.
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Allow to dissolve — GHRP-2 dissolves quickly, 1-3 minutes.
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Verify dissolution — Solution should be clear and colorless.
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Label and store — Refrigerate immediately.
Alternative Reconstitution Options
| BAC Water | Concentration | Best For |
|---|---|---|
| 2mL | 2.5mg/mL | Standard concentration |
| 2.5mL | 2mg/mL | Easy calculations |
| 5mL | 1mg/mL | Very precise measuring |
Dosage Protocol
Concentration Calculations
With 5mg peptide in 2mL BAC water:
- Concentration: 2.5mg/mL = 2500mcg/mL
- Per unit (U-100 syringe): 25mcg per unit
Common Dose Calculations
| Desired Dose | Draw Volume | Syringe Units |
|---|---|---|
| 100mcg | 0.04mL | 4 units |
| 150mcg | 0.06mL | 6 units |
| 200mcg | 0.08mL | 8 units |
| 300mcg | 0.12mL | 12 units |
Doses Per Vial
At 2.5mg/mL concentration (2mL total = 5mg):
| Protocol | Dose | Injections | Duration |
|---|---|---|---|
| 100mcg 2x/day | 100mcg | 50 | 25 days |
| 100mcg 3x/day | 100mcg | 50 | ~17 days |
| 200mcg 2x/day | 200mcg | 25 | ~12 days |
| 200mcg 3x/day | 200mcg | 25 | ~8 days |
Suggested Research Protocols
Protocol A: Standard
- Dose: 100-150mcg
- Frequency: 2-3x daily
- Duration: 8-12 weeks
Protocol B: Enhanced (with GHRH)
- GHRP-2: 100-200mcg
- CJC-1295: 100mcg
- Frequency: 2-3x daily together
- Duration: 8-12 weeks
Protocol C: Higher Dose
- Dose: 200-300mcg
- Frequency: 2-3x daily
- Duration: 8-12 weeks
- Note: Higher doses may increase appetite/cortisol more
Timing Considerations
Optimal injection times:
- Morning (fasted) — First dose
- Post-workout — Second dose
- Before bed — Third dose (most important)
Important:
- Always on empty stomach
- Avoid fatty foods before injection
- Wait 20-30 minutes before eating after injection
Saturation Dose
Research suggests GH release plateaus around 100-200mcg per injection. Doses above 200-300mcg don’t proportionally increase GH release but may increase side effects.
Injection Guide
Subcutaneous Administration
- Clean injection site with alcohol swab
- Pinch skin fold at abdomen or thigh
- Insert needle at 45-90° angle
- Inject slowly
- Wait 5 seconds before withdrawing
Site Rotation
For 2-3x daily dosing:
- Rotate between left/right abdomen
- Alternate thighs
- Vary location each injection
Storage Requirements
Lyophilized (Powder Form)
- Temperature: -20°C (-4°F) or colder
- Duration: 2+ years
Reconstituted (Mixed with BAC Water)
- Temperature: 2-8°C (36-46°F)
- Duration: 3-4 weeks
- Note: GHRP-2 is moderately sensitive; use within 3-4 weeks
Research Considerations
Mechanism of Action
GHRP-2 stimulates GH through:
- Ghrelin receptor binding — GHS-R1a activation
- Direct pituitary action — Somatotroph stimulation
- Hypothalamic effects — May suppress somatostatin
- GH release pattern — Creates GH pulse
Key Effects
| Effect | Level |
|---|---|
| Growth hormone release | Very strong |
| Appetite stimulation | Mild-moderate |
| Cortisol increase | Mild |
| Prolactin increase | Mild |
| IGF-1 elevation | Secondary to GH |
GHRP-2 vs Ipamorelin
| Factor | GHRP-2 | Ipamorelin |
|---|---|---|
| GH release | Stronger | Moderate |
| Appetite | Increased | No change |
| Cortisol | Mild increase | No change |
| Selectivity | Less | More |
| Best for | Max GH release | Clean GH release |
Stacking with GHRH
GHRP-2 + CJC-1295 (no DAC)
- Synergistic GH release
- GHRH amplifies GHRP effect
- Standard combination protocol
GHRP-2 + CJC-1295 DAC
- Weekly DAC + daily GHRP-2
- Sustained baseline + pulses
Sourcing for Research
Source from verified suppliers that provide third-party testing and certificates of analysis (COA) for each batch. Compare purity documentation, shipping conditions, and batch traceability before purchasing research materials.
Scientific References
- Bowers CY. “Growth Hormone-Releasing Peptide (GHRP).” Cell Mol Life Sci. 1998;54(12):1316-1329.
- Arvat E, et al. “Effects of GHRP-2 and Hexarelin on GH, Cortisol, ACTH, and Prolactin Levels.” J Clin Endocrinol Metab. 1997;82(2):3615-3622.
Last updated: December 23, 2025
Disclaimer: This information is for educational and research purposes only. GHRP-2 is a research peptide not intended for human consumption.