GHRP-1
Also known as: Growth Hormone Releasing Peptide 1, GHRP1, GH-RP-1
GHRP-1 is a synthetic growth hormone releasing peptide that stimulates the anterior pituitary gland to increase growth hormone secretion. This hexapeptide was one of the first growth hormone secretagogues developed and serves as a research compound for studying GH release mechanisms.
GHRP-1 is a 873.0 g/mol research peptide. GHRP-1 is a synthetic growth hormone releasing peptide that stimulates the anterior pituitary gland to increase growth hormone secretion. This hexapeptide was one of the first growth hormone secretagogues developed and serves as a research compound for studying GH release mechanisms.
Also called: Growth Hormone Releasing Peptide 1, GHRP1, GH-RP-1
873.0 g/mol
Molecular Weight
Daltons
2
Strong Evidence
benefits
4
Studies Cited
peer-reviewed
1-3
Typical Dose
mcg/kg
Overview
GHRP-1 represents the first generation of growth hormone releasing peptides, developed as a synthetic analog to mimic the natural growth hormone releasing hormone (GHRH) pathway. This hexapeptide binds to specific receptors in the anterior pituitary, triggering a cascade that results in increased growth hormone production and release. Research has focused on GHRP-1's ability to stimulate GH secretion in a pulsatile manner, similar to natural physiological patterns. The peptide works by activating the growth hormone secretagogue receptor (GHSR), also known as the ghrelin receptor, which then stimulates somatotroph cells to release stored growth hormone. Studies have examined GHRP-1's potential applications in understanding growth hormone deficiency, aging-related GH decline, and metabolic regulation. The peptide's mechanism involves calcium influx and cyclic adenosine monophosphate (cAMP) signaling pathways that ultimately lead to growth hormone granule exocytosis. Research has shown that GHRP-1 can produce significant increases in plasma growth hormone levels, though its potency is generally lower compared to newer generation GHRPs. The peptide has been used extensively in laboratory settings to study the hypothalamic-pituitary-growth hormone axis and to investigate potential therapeutic approaches for conditions involving growth hormone insufficiency.
Key Takeaways: GHRP-1
- Strongest evidence supports GHRP-1 for growth hormone stimulation and pituitary function assessment
- Research doses typically range from 1 to 3 mcg/kg via subcutaneous
- 2 benefits with strong evidence, 2 moderate, 2 preliminary
- Half-life: 30-60 minutes
- 4 cited research studies in this guide
Mechanism of Action
GHRP-1 binds to and activates the growth hormone secretagogue receptor (GHSR) located on somatotroph cells in the anterior pituitary gland. This binding triggers intracellular signaling cascades involving calcium influx and cAMP elevation, leading to the release of stored growth hormone from secretory vesicles. The peptide also influences hypothalamic function by reducing somatostatin release, which normally inhibits GH secretion, creating a dual mechanism for enhanced growth hormone output.
Research Benefits
GHRP-1 at a Glance
GHRP-1 binds to and activates the growth hormone secretagogue receptor (GHSR) located on somatotroph cells in the anterior pituitary gland.
Growth Hormone Stimulation
Strong EvidenceGHRP-1 directly stimulates the release of growth hormone from anterior pituitary somatotroph cells through GHSR activation, leading to measurable increases in plasma GH levels within 15-30 minutes of administration.
Pituitary Function Assessment
Strong EvidenceClinical studies have used GHRP-1 as a diagnostic tool to evaluate pituitary responsiveness and growth hormone reserve capacity in research subjects with suspected GH deficiency.
Metabolic Research Applications
Moderate EvidenceResearch demonstrates GHRP-1's utility in studying metabolic processes regulated by growth hormone, including glucose metabolism, lipid oxidation, and protein synthesis pathways.
Aging-Related GH Decline Studies
Moderate EvidenceResearch has examined GHRP-1's ability to stimulate GH release in older subjects, providing insights into age-related changes in the growth hormone axis.
Sleep and Circadian Rhythm Research
PreliminaryStudies have investigated GHRP-1's effects on growth hormone pulsatility and its relationship to sleep patterns and circadian rhythms.
Muscle Protein Synthesis Investigation
PreliminaryResearch has explored GHRP-1's indirect effects on muscle protein synthesis through its stimulation of growth hormone and subsequent IGF-1 elevation.
Research Dosing Protocols
Research Purposes Only: All content is for informational and research purposes only. This site does not provide medical advice, diagnosis, or treatment. Consult a qualified healthcare professional before using any peptide or supplement.
| Research Protocol | Dose Range | Route |
|---|---|---|
| GH stimulation testing | 1–3 mcg/kg | subcutaneous |
| Pituitary function assessment | 100–300 mcg | subcutaneous |
| Metabolic research | 0.5–2 mcg/kg | intravenous |
Frequency
Single dose for acute studies, or 2-3 times daily for extended research protocols
Timing
Morning administration on empty stomach, or 2-3 hours after meals
Cycle Length
Acute studies: single dose; Extended protocols: 7-14 days maximum
Research Notes
- 1GH response typically peaks 15-30 minutes post-administration
- 2Fasting state enhances GH response to GHRP-1
- 3Research purposes only - not approved for human therapeutic use
- 4Monitor blood glucose levels during research protocols
- 5Refrigerated storage required for reconstituted solution
Reconstitution Guide
Standard Reconstitution
Vial Size
2 mg
Bacteriostatic Water
2 mL
Concentration
10 mcg
per 0.1 mL (10 units)
Step-by-Step Guide
Gather Materials
GHRP-1 vial, bacteriostatic water, alcohol swabs, insulin syringes.
Equilibrate Temperature
Remove the vial from storage and allow it to reach room temperature (5-10 minutes).
Sanitize
Swab the rubber stopper of both the peptide vial and bacteriostatic water vial with alcohol.
Draw Water
Draw 2 mL of bacteriostatic water into a syringe.
Add Water to Vial
Insert the needle into the peptide vial and direct the water stream against the glass wall — not directly onto the powder.
Mix Gently
Swirl the vial gently until the powder is fully dissolved. Never shake. The solution should be clear and colorless.
Store Properly
Refrigerate at 2-8°C refrigerated. 14 days once reconstituted.
Storage Temperature
2-8°C refrigerated
Shelf Life
14 days once reconstituted
Important Notes
- •Use bacteriostatic water for injection
- •Allow vial to reach room temperature before reconstitution
- •Inject water slowly down the side of the vial
- •Gently swirl - do not shake vigorously
- •Store reconstituted solution protected from light
- •Single-use vials should not be shared between subjects
GHRP-1 Dosing Calculator
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GHRP-1 Reconstitution Calculator
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Safety & Side Effects
Reported Side Effects
- !Mild injection site irritation or redness
- !Transient hypoglycemia
- !Water retention
- !Joint stiffness or discomfort
- !Fatigue or drowsiness post-injection
- !Nausea or mild gastrointestinal upset
- !Headache
- !Dizziness or lightheadedness
- !Temporary numbness or tingling in extremities
- !Potential insulin sensitivity changes
Potential Interactions
- ⚡May enhance hypoglycemic effects of diabetes medications
- ⚡Could interact with corticosteroids affecting GH response
- ⚡Potential interactions with thyroid hormones
- ⚡May influence insulin sensitivity and glucose metabolism
- ⚡Could affect the efficacy of other growth hormone modulators
Important: Side effects and interactions listed here are compiled from published research and community reports. This is not a complete list. No formal drug interaction studies have been conducted for most research peptides. Always consult a qualified healthcare provider.
Research Studies
The following studies are referenced in this profile. PubMed IDs are provided where available for independent verification.
Growth hormone-releasing peptide-1 (GHRP-1) stimulates growth hormone release in normal men
Demonstrated significant GH stimulation following GHRP-1 administration in healthy male subjects, establishing dose-response relationships and timing of peak GH release.
Characterization of the growth hormone secretagogue receptor and its role in growth hormone release
Comprehensive review of GHSR mechanism and GHRP-1's role in elucidating growth hormone release pathways and receptor pharmacology.
Effects of growth hormone-releasing peptides on sleep and growth hormone secretion
Investigated the relationship between GHRP-1 administration, sleep architecture, and nocturnal growth hormone secretion patterns.
Diagnostic utility of growth hormone releasing peptides in assessment of pituitary function
Evaluated GHRP-1 as a diagnostic tool for assessing growth hormone reserve and pituitary responsiveness in various clinical populations.
Note: This is not an exhaustive list of all published research. Studies are selected for relevance and quality. Click PubMed IDs to verify sources independently. Inclusion does not imply endorsement of the peptide for any clinical use.
Frequently Asked Questions
GHRP-1 was the first synthetic growth hormone releasing peptide developed, with lower potency compared to GHRP-2 and GHRP-6. It produces measurable GH stimulation but requires higher doses and has a shorter duration of action than later generations.
GHRP-1 typically stimulates growth hormone release within 15-30 minutes of administration, with peak GH levels occurring around 30-60 minutes post-injection in research studies.
No, GHRP-1 has extremely poor oral bioavailability (less than 5%) due to peptide degradation in the digestive system. Research protocols use subcutaneous or intravenous administration for effective GH stimulation.
Yes, both lyophilized powder and reconstituted GHRP-1 should be stored at 2-8°C. Once reconstituted with bacteriostatic water, the solution remains stable for up to 14 days when properly refrigerated.
Research doses typically range from 1-3 mcg/kg bodyweight or 100-300 mcg total dose, administered subcutaneously. Exact dosing depends on the specific research protocol and objectives.
GHRP-1 works through a different receptor pathway (GHSR) compared to natural GHRH, producing a more robust and consistent GH response. It also has synergistic effects when combined with GHRH in research settings.
Research subjects with active cancer, uncontrolled diabetes, or severe cardiovascular disease should be excluded from GHRP-1 studies due to potential growth hormone effects on these conditions.
Yes, GHRP-1 can cause transient hypoglycemia in some research subjects, likely due to acute growth hormone effects on glucose metabolism. Blood glucose monitoring is recommended during research protocols.
Research & Educational Use Only
All content is for informational and research purposes only. This site does not provide medical advice, diagnosis, or treatment. Consult a qualified healthcare professional before using any peptide or supplement.
The information presented here is compiled from published research studies and is intended for informational purposes only. Individual results may vary. Always consult with a licensed healthcare provider.