GHRP-2 Dosage Protocol (5 mg & 10 mg Vials)
Quickstart Highlights
GHRP-2 (pralmorelin) is a synthetic hexapeptide that potently stimulates growth hormone release by activating ghrelin receptors in the pituitary and hypothalamus[1][2]. It has been used in clinical research as a diagnostic GH stimulant and in investigative treatment protocols for growth hormone deficiency[3]. This educational protocol presents a once‑daily subcutaneous approach using practical dilutions for clear insulin‑syringe measurements.
- Multiple vial sizes: Choose from 5 mg or 10 mg vials to match your protocol needs.
- Daily dose range: 100–300 mcg (0.1–0.3 mg) once daily (gradual escalation protocol).
- Convenient dosing: Each vial size has optimized reconstitution for easy insulin syringe measurements.
- Storage: Lyophilized: freeze at −20 °C (−4 °F); after reconstitution, refrigerate at 2–8 °C (35.6–46.4 °F) and use within 28 days.
Dosing & Reconstitution Guide
Educational guide for all vial sizes - choose your optimal concentration
5 mg Vial Protocol (3 mL = ~1.67 mg/mL)
| Week | Daily Dose | Units (per injection) (mL) |
|---|---|---|
| Weeks 1–2 | 100 mcg (0.1 mg) | 6 units (0.06 mL) |
| Weeks 3–4 | 150 mcg (0.15 mg) | 9 units (0.09 mL) |
| Weeks 5–8 | 200 mcg (0.2 mg) | 12 units (0.12 mL) |
| Weeks 9–12 | 200 mcg (0.2 mg) | 12 units (0.12 mL) |
| Weeks 13–16 | 200 mcg (0.2 mg) | 12 units (0.12 mL) |
Reconstitution: Add 3.0 mL bacteriostatic water → ~1.67 mg/mL concentration. At this concentration, 1 unit = 0.01 mL ≈ 16.7 mcg on a U‑100 insulin syringe. Ideal for low-volume daily dosing. For ≤10-unit (≤0.10 mL) administrations, consider 30- or 50-unit insulin syringes for improved readability.
10 mg Vial Protocol (3 mL = ~3.33 mg/mL)
| Week | Daily Dose | Units (per injection) (mL) |
|---|---|---|
| Weeks 1–2 | 100 mcg (0.1 mg) | 3 units (0.03 mL) |
| Weeks 3–4 | 150 mcg (0.15 mg) | 4.5 units (0.045 mL) |
| Weeks 5–8 | 200 mcg (0.2 mg) | 6 units (0.06 mL) |
| Weeks 9–12 | 200 mcg (0.2 mg) | 6 units (0.06 mL) |
| Weeks 13–16 | 200 mcg (0.2 mg) | 6 units (0.06 mL) |
Reconstitution: Add 3.0 mL bacteriostatic water → ~3.33 mg/mL concentration. At this concentration, 1 unit = 0.01 mL ≈ 33.3 mcg on a U‑100 insulin syringe. More concentrated for smaller injection volumes. For ≤10-unit (≤0.10 mL) administrations, consider 30- or 50-unit insulin syringes for improved readability.
Reconstitution Steps (All Vial Sizes)
- Draw appropriate volume of bacteriostatic water with a sterile syringe.
- Inject slowly down the vial wall to minimize foaming; avoid shaking.
- Gently swirl or roll the vial until the powder is fully dissolved.
- Label the vial with the reconstitution date and refrigerate at 2–8 °C (35.6–46.4 °F), protected from light.
- Use reconstituted solution within 28 days for maximum potency and safety[8].
Supplies Needed
Plan based on an 8–16 week daily protocol with gradual titration.
- Peptide Vials (GHRP-2): Choose your preferred vial size (5 mg or 10 mg).
- Insulin Syringes (U‑100, 1 mL): For ≤10-unit doses, 30‑ or 50‑unit syringes recommended for precision.
- Per week: 7 syringes (1/day)
- 8 weeks: 56 syringes
- 12 weeks: 84 syringes
- 16 weeks: 112 syringes
- Bacteriostatic Water (10 mL bottles): Use 3.0 mL per vial for reconstitution.
- 8 weeks (5 mg: 2 vials / 10 mg: 1 vial): 6 mL or 3 mL → 1 × 10 mL bottle
- 12 weeks (5 mg: 4 vials / 10 mg: 2 vials): 12 mL or 6 mL → 2 × 10 mL or 1 × 10 mL bottles
- 16 weeks (5 mg: 5 vials / 10 mg: 3 vials): 15 mL or 9 mL → 2 × 10 mL or 1 × 10 mL bottles
- Alcohol Swabs: One for the vial stopper + one for the injection site each day.
- Per week: 14 swabs (2/day)
- 8 weeks: 112 swabs → recommend 2 × 100‑count boxes
- 12 weeks: 168 swabs → recommend 2 × 100‑count boxes
- 16 weeks: 224 swabs → recommend 3 × 100‑count boxes
- Sharps Container: 1‑quart container holds ~100 syringes; 2‑quart for longer protocols.
Protocol Overview
Concise summary of the once‑daily regimen.
- Goal: Stimulate endogenous growth hormone secretion through ghrelin receptor activation[1].
- Schedule: Daily subcutaneous injections for 8–12 weeks (extend to 16 weeks if desired).
- Dose Range: 100–300 mcg daily with gradual titration; higher doses show dose-dependent responses but may offer limited added benefit with routine use[4].
- Vial Options: 5 mg or 10 mg vials with optimized reconstitution for each size.
- Storage: Lyophilized frozen at −20 °C (−4 °F); reconstituted refrigerated at 2–8 °C (35.6–46.4 °F); use within 28 days.
Dosing Protocol
Suggested daily titration approach based on clinical studies[2][3][4].
- Weeks 1–2: 100 mcg once daily to establish baseline tolerance.
- Weeks 3–4: 150 mcg once daily to enhance GH response if well tolerated.
- Weeks 5–16: 200 mcg once daily for maximal effect in most research scenarios; advanced researchers may optionally increase to 250–300 mcg.
- Frequency: Once per day (subcutaneous); evening administration may align with nocturnal GH rhythms.
- Cycle Length: 8–16 weeks; some attenuation may occur in first 1–2 weeks but response stabilizes with continued dosing[3].
Storage Instructions
Proper storage preserves peptide quality and efficacy[8][9].
- Lyophilized (powder): Store at −20 °C (−4 °F) in dry, dark conditions; stable at room temperature for short periods but freezer storage maximizes shelf life[8].
- Reconstituted (solution): Refrigerate at 2–8 °C (35.6–46.4 °F) and do not freeze; use within 28 days for maximum potency[9].
- Shelf life: Use reconstituted solution within 28 days; the benzyl alcohol in bacteriostatic water inhibits bacterial growth but solutions should still be discarded after approximately 4 weeks.
- Allow vials to reach room temperature before opening to minimize condensation uptake. Always protect from light and heat.
Important Notes
Practical considerations for consistency and safety.
- Use new sterile insulin syringes for each injection; dispose in a proper sharps container[10].
- Rotate injection sites systematically (abdomen, thighs, upper arms) to reduce local irritation and avoid lipodystrophy[13].
- Very frequent dosing (e.g., every 2 hours) can cause progressive attenuation due to acute tachyphylaxis[3]; once-daily administration avoids this issue.
- Multiple daily injections (2–3×) have been explored but require strict adherence and may offer limited added benefit[5][6].
- Document daily dose and site rotation to maintain consistency.
- A 5‑days‑on/2‑days‑off schedule may help maintain GH response sensitivity over long protocols[7].
How This Works
GHRP-2 is a synthetic growth hormone secretagogue that binds to and activates ghrelin (GHS-R1a) receptors[1]. By binding to receptors in both the pituitary and hypothalamus, it triggers robust, pulsatile GH release that mimics natural secretion patterns[2]. Clinical studies have demonstrated that even a single 100 mcg subcutaneous dose can raise GH levels several‑fold above baseline[4]. When administered consistently, GHRP-2 can elevate IGF‑1 levels over weeks to months (~50% increase reported in some studies)[5]. However, the GH response may attenuate with continuous daily use (tachyphylaxis), which is why titration strategies and periodic breaks are often incorporated[4][7]. The peptide has been well tolerated in clinical trials with no significant adverse effects or toxicity reported at these dosage ranges[2][7].
Potential Benefits & Side Effects
Observations from clinical and preclinical literature[1][2][3][4][5][6][7].
Potential Benefits:
- Potent GH stimulation: Robust, pulsatile release without suppressing natural production[1].
- IGF‑1 elevation: Sustained administration can significantly increase IGF‑1 levels[5].
- Clinical diagnostic use: Used as a diagnostic tool for GH deficiency evaluation[3].
- Combination therapy: In combination with GHRH analogs, can further amplify GH/IGF‑1 axis[5][6].
- Generally well tolerated: Placebo-like safety profile in clinical studies[7].
Potential Side Effects:
- Increased appetite (most common): Ghrelin‑mimetic action, especially shortly after injection[1].
- Injection‑site reactions: Mild redness, irritation (generally transient).
- Transient effects: Mild flushing, warmth, or tingling.
- Possible mild hormonal increases: Cortisol and prolactin at higher doses[6].
- Response attenuation: Tachyphylaxis with continuous daily dosing[4].
- High-dose effects: Water retention or joint stiffness with prolonged high‑dose use (≥300 mcg/day).
Lifestyle Factors
Complementary strategies for optimal outcomes.
- Administer on an empty stomach or before sleep to optimize GH pulse amplitude.
- Maintain adequate protein intake and balanced nutrition to support the anabolic effects of elevated GH.
- Combine resistance training and aerobic activity to support body composition benefits.
- Prioritize 7–9 hours of quality sleep to synergize with natural nocturnal GH secretion.
- Manage stress effectively, as elevated cortisol can blunt GH response.
- Stay well hydrated to support metabolic processes.
Injection Technique
General subcutaneous guidance from clinical best‑practice resources[10][11][12].
- Clean the vial rubber stopper and chosen skin site with separate alcohol swabs; allow both to dry completely before proceeding[11].
- Use a fine insulin syringe (typically 29–31 gauge, 0.5‑inch needle). For ≤10‑unit doses, 30‑ or 50‑unit syringes improve readability.
- Pinch a fold of skin (abdomen, thigh, or outer upper arm); insert needle at a 45–90° angle into subcutaneous tissue (fatty layer, not muscle)[10][12]. (Use 90° angle if ample fatty tissue; 45° for leaner individuals.)
- Do not aspirate (pull back the plunger) when giving a subcutaneous injection — aspiration is unnecessary and can cause tissue trauma[10].
- Inject the solution slowly and steadily; wait a few seconds after injection before withdrawing the needle to ensure complete delivery and minimize leakage.
- Withdraw the needle and apply light pressure with a clean swab; avoid rubbing vigorously.
- Rotate injection sites systematically with each daily injection to prevent lipodystrophy — space injections at least 1 inch apart[13].
- Dispose of used syringes and needles immediately in a proper FDA‑approved sharps container[12].
Recommended Source
We recommend Legion Peptides for high‑purity GHRP-2 in both vial sizes (5 mg and 10 mg).
Why Legion Peptides?
- High‑purity, third‑party‑tested peptides with batch‑specific Certificates of Analysis (COAs).
- Consistent, ISO‑aligned handling and quality documentation.
- Reliable fulfillment with cold‑chain integrity to preserve peptide stability.
- Transparent testing and verification processes for research‑grade peptides.
- Multiple vial sizes to match different protocol needs and durations.
Important Note
This content is for educational purposes only and is not medical advice. GHRP-2 is for research use only. Not for human consumption. Always consult with qualified professionals before starting any peptide research protocol.
References
-
Domest Anim Endocrinol – Effects of GHRP-2 on GH release — Mechanism and receptor activation in swine
-
J Clin Endocrinol Metab – GHRP-2 in GH-deficient children — Eight months treatment with graded doses
-
Eur J Endocrinol – Five‑day GHRP-2: attenuation and IGF‑I — Response attenuation in healthy young men
-
Endocrine – GH/IGF‑1 response to GHRP-2 in older adults — Acute and chronic effects
-
Am J Men's Health – GH secretagogue raises IGF‑1 — ~50% increase over 3 months in hypogonadal men
-
Sex Med Rev (PMC) – Safety and efficacy of GH secretagogues — Comprehensive review
-
Asian-Australas J Anim Sci – Twice‑daily GHRP-2 effects — IGF‑1 and tachyphylaxis patterns
-
Sigma-Aldrich – Peptide storage guidelines — Lyophilized storage at −20 °C; reconstituted use within 4 weeks
-
Mountainside Medical – Bacteriostatic Water guidelines — Multi‑dose vial guidelines; 28‑day use recommendation
-
Usach I. et al. (2019) – Subcutaneous injection technique — Factors influencing pain and proper technique
-
MedlinePlus – Subcutaneous (SQ) Injections — Site selection, angle guidance, rotation best practices
-
CDC – Vaccine Administration: Subcutaneous Route — Clinical guidelines for angle, site selection, no‑aspiration
-
Medicine LibreTexts – Site rotation and lipodystrophy prevention — Subcutaneous injection best practices
-
Legion Peptides – GHRP-2 product page — Quality documentation and batch COAs
