Educational use only — not medical advice. This guide summarizes information reported in published research and community practice for educational purposes. It is not medical advice and not a recommendation to use any compound. Any doses, schedules, or combinations shown are examples of what has been reported, not instructions for you. Many peptides described here are research compounds that are not FDA-approved for the uses discussed and may be investigational or restricted. Effects, risks, and legal status vary; individual needs and results vary. Consult a qualified, licensed healthcare professional before making any decision. Do not use this content to diagnose, treat, or dose yourself.
GHRP-2 at a glance
- What it is
- A synthetic hexapeptide (pralmorelin) that acts as a growth hormone secretagogue / ghrelin-receptor (GHS-R1a) agonist
- Researched for
- Growth hormone release; approved in Japan only as a diagnostic agent for GH deficiency, investigational elsewhere
- Commonly reported range
- 100-300 mcg per injection (community-reported examples)
- Route reported
- Subcutaneous injection (intravenous in the clinical diagnostic setting)
- Reported frequency
- 1-3 times daily, often including a bedtime dose
- Reported cycle
- Community-reported cycles of roughly 8-12 weeks
- Plasma half-life
- Approximately 1-2 hours (GH pulse peaks 15-30 minutes post-dose)
- Regulatory status
- Not FDA-approved; WADA-prohibited at all times (S2); research-use-only in the US
Reported ranges from research/community — examples, not recommendations.
What it is / mechanism
GHRP-2, also known as pralmorelin, is a synthetic hexapeptide that mimics the endogenous hormone ghrelin. It binds to and activates the growth hormone secretagogue receptor (GHS-R1a), primarily in the pituitary and hypothalamus. Receptor activation signals through the Gq/11-phospholipase-C-IP3-calcium pathway, promoting the pulsatile release of endogenous growth hormone from pituitary somatotrophs. Unlike GHRH analogs, which act on a separate receptor, GHRP-2 works through the ghrelin pathway, so the two classes are reported to act synergistically when combined. Because it stimulates the body's own GH pulses rather than supplying exogenous hormone, it is often described in research literature as preserving physiological feedback.
Researched effects
In research and clinical-diagnostic settings, GHRP-2 has been reported to produce sharp, dose-dependent increases in circulating growth hormone, with single subcutaneous doses raising peak GH severalfold above baseline within roughly 15-30 minutes. Because it shares the ghrelin pathway, appetite stimulation is also commonly reported, though generally described as milder than with GHRP-6. Community reports discuss downstream interest in recovery, body composition, and sleep, but these are research findings and anecdotes, not guaranteed outcomes. Individual response varies with dose, timing, and physiology.
Evidence & regulatory status
- Evidence: GHRP-2 (pralmorelin) has been characterized in pharmacology studies as a potent GHS-R1a agonist that reliably triggers dose-dependent GH release; it is used clinically in Japan as an intravenous diagnostic agent for growth hormone deficiency.
- Regulatory: Not approved by the FDA for any therapeutic indication; sold in the US strictly as a research chemical (research-use-only). It is prohibited at all times by WADA under the S2 peptide-hormone category.
- Research-use: Long-term human safety data outside the diagnostic context are limited; most reported physique/performance uses are community-reported rather than established in controlled trials.
Dosage — reported ranges (overview)
The figures below are examples of what is reported in research literature and community sources, not a recommendation or a personal dose. Reported subcutaneous examples cluster around 100-300 mcg per injection, given one to three times daily, with a common example being a 100 mcg dose before bed to align with the natural nocturnal GH surge. Reports note that the GH-releasing effect appears to plateau near a saturation dose of roughly 1-2 mcg/kg, so examples above about 300 mcg per injection are described as offering diminishing returns.
A printable protocol sheet with a reconstitution reference and an injection log comes with All-Access Lifetime.
Reconstitution — bac-water math
Reconstitution is concentration math only, not a personal dose. GHRP-2 ships as a lyophilized powder and is reconstituted with bacteriostatic water. For a microgram-dosed peptide, the concentration in mcg/mL equals the vial amount in mg times 1000, divided by the mL of water added: concentration = (mg x 1000) / mL. On a U-100 insulin syringe, units to draw = dose in mcg / concentration x 100. Worked example: a 5 mg vial reconstituted with 2 mL of water gives (5 x 1000) / 2 = 2500 mcg/mL, so a 100 mcg example dose = 100 / 2500 x 100 = 4 units on a U-100 syringe.
| Bac water added | Concentration | 100 mcg (low example) | 300 mcg (high example) |
|---|
| 1 mL | 5000 mcg/mL | 2 units | 6 units |
| 2 mL | 2500 mcg/mL | 4 units | 12 units |
| 3 mL | 1667 mcg/mL | 6 units | 18 units |
This is concentration math, not a dose recommendation.
Injection / administration basics
In research contexts GHRP-2 is described as a subcutaneous injection, typically into the fatty tissue of the abdomen, using a U-100 insulin syringe. It is commonly reported to be used on an empty stomach because food, particularly carbohydrates and fats, is described as blunting the GH pulse. Reconstituted solution is drawn to the units indicated by the concentration math above. This describes reported handling for research purposes and is not medical or administration advice.
Half-life & frequency rationale
GHRP-2 has a reported plasma half-life of roughly 1-2 hours. The growth-hormone pulse it triggers peaks quickly, within about 15-30 minutes of a subcutaneous dose, and the elevated GH generally subsides over the following 2-3 hours. This short window is the reason multiple daily doses appear in reported protocols.
Side effects, safety & contraindications
Commonly reported effects in research and community sources include increased appetite (via the ghrelin pathway), transient water retention, tingling or head-rush sensations shortly after injection, and injection-site reactions. Because GHRP-2 raises GH and downstream IGF-1, reports also mention the theoretical concerns common to GH secretagogues, such as effects on insulin sensitivity, cortisol and prolactin, and fluid balance. Human safety data outside the short-term diagnostic setting are limited, and long-term effects are not well characterized. This is not a complete list and not medical advice.
Stacking — overview
GHRP-2 is most often discussed alongside a GHRH analog, because the two act on different receptors and are reported to produce a synergistic GH release greater than either alone. Community and research discussions pair it with compounds in our library such as CJC-1295, Ipamorelin, Sermorelin, and Tesamorelin. These are examples of reported pairings for educational purposes, not recommendations.
GHRP-2 + CJC-1295
A GHRP (ghrelin-receptor agonist) paired with a GHRH analog; the classic reported synergistic GH-release combination
GH-pulse stack
GHRP-2 with Ipamorelin and CJC-1295, reported for a fuller GH pulse profile
GHRP-2 + Sermorelin
GHRP-2 combined with the GHRH analog Sermorelin as an alternate GHRH pairing
GHRP-2 + Tesamorelin
A GHRP paired with the stabilized GHRH analog Tesamorelin, reported in body-composition-focused discussions
Stacking across compounds
The overview above covers GHRP-2. The cross-compound material — which pairings are redundant rather than additive, where interaction risk is documented versus merely unstudied, and the blend arithmetic worked end to end — lives in the Peptide Stacking Guide, which is free to read in outline and $39 in full (included with All-Access Lifetime).
Included with this guide
The GHRP-2 Stacking Module
The overview above is the free summary. The GHRP-2 Stacking Module goes through each combination in depth — the mechanism-level reason it is proposed, what is actually reported in practice, and the cautions specific to that pairing — plus what to avoid and why. Included with GHRP-2 Standard Access.
- How to think about stacking GHRP-2 — 4 principles
- 3 combinations covered in detail
- What to avoid, and why — 3 items
- Combination-specific cautions
Combinations covered: GHRP-2 + CJC-1295, GHRP-2 + Sermorelin, GHRP-2 + Tesamorelin.
For how combinations are grouped by research context, the named blends, and why a pre-mixed blend vial cannot be calculated from its total milligrams, see the peptide stacks guide.
Storage & handling
- Lyophilized (powder): reported as stable refrigerated at 2-8 C, and for longer terms frozen; kept sealed and away from light.
- Reconstituted (in bacteriostatic water): refrigerated at 2-8 C and typically reported as used within about 3-4 weeks; do not freeze the reconstituted solution.
References
Reported facts in this guide are drawn from peptide pharmacology literature, GHRP-2 (pralmorelin) diagnostic-use data, and the WADA Prohibited List; all figures are educational examples, not medical advice.
Related peptide guides
Continue exploring related educational guide topics in the Medibact library.
Guide FAQ
Quick answers about guide scope, access, and educational use context.
What is GHRP-2?
GHRP-2, or pralmorelin, is a synthetic hexapeptide that acts as a ghrelin-receptor (GHS-R1a) agonist and stimulates the body's own release of growth hormone. It is approved in Japan only as a diagnostic agent for GH deficiency and is not FDA-approved; in the US it is sold for research use only.
How is GHRP-2 different from GHRP-6?
Both are ghrelin-receptor agonists, but GHRP-2 is reported to produce higher GH pulse amplitudes at equivalent doses while causing somewhat less appetite stimulation than GHRP-6. These are reported comparisons, not guarantees.
Why is GHRP-2 often combined with a GHRH analog?
GHRP-2 and GHRH analogs such as CJC-1295 or Sermorelin act on different receptors, so research reports describe a synergistic GH release when they are combined, greater than either compound alone. This is described as an example pairing, not a recommendation.
What is the reported half-life of GHRP-2?
Its plasma half-life is reported at roughly 1-2 hours, with the GH pulse peaking about 15-30 minutes after a subcutaneous dose and subsiding over the next few hours.
Is GHRP-2 legal or allowed in sport?
It is not FDA-approved for therapeutic use and is sold in the US as a research chemical only. It is prohibited at all times by WADA under the S2 peptide-hormone category, so it is banned in sanctioned sport.
Compliance and trust notes
- Educational content only; no personalized health or outcome claims.
- No personalized use recommendation outputs.
- Use this material for general learning and research-context literacy.
