GHRP-2

GHRP-2 acts as a potent and selective agonist of the growth hormone secretagogue receptor type 1a (GHS-R1a), a G protein-coupled receptor located in the pituitary gland and hypothalamus.

• GHS-R1a binding: GHRP-2 binds to the same receptor as ghrelin, activating the phospholipase C (PLC) and protein kinase C (PKC) signaling pathway.
• GH release: Receptor activation induces GH release from somatotrophs in the anterior pituitary, increasing serum GH levels.
• Hypothalamic modulation: It also acts at the hypothalamic level, increasing GHRH (GH-releasing hormone) secretion and antagonizing somatostatin, thereby potentiating GH release.
• Pulsatile effect: The induced GH release is pulsatile, mimicking the physiological pattern, with a peak at 15-30 minutes after administration.

• GH deficiency diagnosis: Used in stimulation tests to evaluate GH/IGF-1 axis function in patients with suspected growth hormone deficiency.
• Anti-aging research: Studied for its potential to increase muscle mass, reduce body fat, and improve bone density in older adults.
• Athletic performance: Used by athletes to enhance muscle recovery, increase lean mass, and reduce fat, though its use is banned by the World Anti-Doping Agency (WADA).
• Sarcopenia and osteoporosis treatment: Under investigation to counteract age-related loss of muscle and bone mass.

GHRP-2 produces a significant and rapid increase in serum GH levels, followed by an increase in IGF-1. Reported effects include improved body composition (increased lean mass, reduced fat), enhanced muscle recovery, increased bone density, improved sleep quality, and a sense of well-being. It may also improve immune function and wound healing. However, long-term effects are not well documented due to the lack of extensive clinical studies.

GHRP-2 is not approved by the FDA or EMA for general clinical use. Its use is banned in sports by WADA. Potential adverse effects include increased appetite (though less than with ghrelin), fluid retention, joint pain, carpal tunnel syndrome, transient hyperglycemia, and possible increased cancer risk due to chronic IGF-1 elevation. It is contraindicated in patients with active tumors, uncontrolled diabetes, severe hypertension, pregnancy, and lactation. Administration must be under strict medical supervision. Dosage and treatment duration should be carefully monitored to avoid adverse effects.

GHRP-2 is not approved by the FDA (USA) or EMA (Europe) for general clinical use. In some countries such as Japan and South Korea, it has been used as a diagnostic tool in GH stimulation tests under local regulatory approval. It is not classified as an approved drug for specific conditions. Its use in research and sports medicine is common but unregulated as a pharmaceutical.

Typical research dosage is 100-200 mcg subcutaneously, 1-3 times daily. For diagnostic tests, 1-2 mcg/kg is administered intravenously. There is no standard approved dose for clinical use. Treatment duration should not exceed 8-12 weeks without medical supervision. It is recommended to start with low doses and increase gradually based on response and tolerance.

Lyophilized GHRP-2 should be stored at -20°C (freezer) in a dry, dark place. Once reconstituted with bacteriostatic water or sterile saline, it should be refrigerated at 2-8°C and used within 7-14 days. Do not freeze after reconstitution. Protect from direct light and avoid excessive agitation.