Sermorelin
Also known as: GRF 1-29 · Geref
A bioidentical GHRH analog representing the first 29 amino acids of natural GHRH, providing the most physiologically natural approach to GH stimulation.
Overview
Sermorelin is a synthetic peptide consisting of the first 29 amino acids of the 44-amino-acid human growth hormone releasing hormone (GHRH). It represents the minimum fragment of GHRH required for full biological activity. Unlike synthetic HGH, Sermorelin works by stimulating the pituitary gland to produce and secrete its own growth hormone, preserving the natural pulsatile pattern and feedback mechanisms. This makes it one of the safest approaches to growth hormone optimization.
Sermorelin was previously FDA-approved (as Geref) for diagnosing and treating growth hormone deficiency in children, though it was voluntarily withdrawn from the market for commercial reasons, not safety concerns. It remains widely used in anti-aging and regenerative medicine clinics. The peptide is typically administered before bedtime to coincide with the body's natural GH secretion peak during deep sleep.
Mechanism of Action
Binds to GHRH receptors on anterior pituitary somatotrophs, stimulating the natural synthesis and pulsatile release of growth hormone. Preserves the hypothalamic-pituitary feedback loop, preventing GH receptor desensitization.
Key Benefits
Potential Side Effects
Common Stacks
This peptide is commonly combined with the following compounds for synergistic effects:
Known Interactions
The following interactions have been documented for Sermorelin. Always consult a healthcare professional before combining compounds.
Use Caution (1)
Both are GHRH analogs competing for the same receptor. Using together provides diminishing returns and may desensitize GHRH receptors faster.
Synergistic (1)
Sermorelin (GHRH) + Ipamorelin (GHRP) is a well-studied combination that amplifies GH release through complementary pathways without significant cortisol or prolactin elevation.
Scientific References
Quick Reference
Typical Dose
200-300 mcg
Frequency
Once daily, typically before bedtime
Route
Subcutaneous injection
Half-Life
~10-20 minutes
Cycle Length
3-6 months continuous, then reassess
FDA Status
Previously FDA approved (Geref); voluntarily withdrawn
Need to calculate dosing?
Use our reconstitution calculator to determine exact syringe measurements.
Open CalculatorThis information is for educational purposes only. Consult a qualified healthcare professional before using any peptide. Dosing information reflects commonly reported protocols and may not be appropriate for everyone.
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