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GHRP-2 Guide: Available Now
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.
The full step-by-step protocol examples, titration, and printable protocol sheet are planned for a future paid Protocol Playbook module.
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.
Pre-fills example values. Every field remains editable.
The amount printed on the vial or listed on a product page.
mL
Liquid volume used for the concentration calculation.
The mass amount to convert into liquid volume for this math example.
4. Insulin syringe size
Your result
Syringe-unit reading
10 units
= 0.1 mL · 250 mcg target amount
Concentration
2.5mg/mL
Per insulin unit
25mcg
Portions per vial
20
Volume
0.1mL
This calculator is an educational tool for laboratory and research math only. The peptides referenced are research compounds not intended for human or veterinary use, and example values are not medical advice or personal-use instructions. Follow applicable research protocols and regulations.
How the calculator works
Concentration
peptide ÷ liquid
Total peptide divided by liquid volume gives the concentration per mL.
Volume
target ÷ concentration
The target mass divided by concentration gives the liquid volume.
Syringe units
volume × 100
For insulin units, 100 units equals 1 mL, so mL is multiplied by 100.
Worked example: A 5 mg vial plus 2 mL liquid creates a 2.5 mg/mL concentration. A 250 mcg target amount equals 0.1 mL, or 10 insulin units. The vial contains 20 such portions.
Frequently asked questions
How much bacteriostatic water should I enter?+
There is no single calculator-default amount. The liquid volume controls concentration: more liquid creates a less concentrated solution and a larger volume reading for the same target amount; less liquid creates a more concentrated solution and a smaller volume reading.
How do insulin syringe units relate to mL?+
For this math tool, 100 insulin units equals 1 mL, and 1 unit equals 0.01 mL. The 0.3 mL, 0.5 mL, and 1.0 mL options change capacity, not the unit-to-mL relationship.
What is the difference between mg, mcg, and units?+
Milligrams and micrograms measure peptide mass: 1 mg = 1,000 mcg. Syringe units measure liquid volume. Reconstitution math connects mass and volume by using concentration.
Does changing the liquid volume change the total peptide in the vial?+
No. The total peptide amount entered for the vial remains fixed. Changing the liquid volume only changes concentration and the resulting volume shown by the calculator.
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
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.
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.
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.
