Sermorelin
Also known as GRF(1-29), Geref
Sermorelin is a synthetic fragment of the first 29 amino acids of natural growth hormone releasing hormone (GHRH), retaining the full biological activity of the native hormone. It was previously marketed as an FDA-approved diagnostic and treatment agent (Geref) before being discontinued for commercial reasons, and it has a long clinical history in GH deficiency evaluation and pediatric treatment. Because it works through the pituitary's own GHRH receptors rather than replacing GH directly, it preserves natural feedback regulation, which is commonly cited as a safety advantage. It remains widely used in physician-supervised anti-aging and wellness protocols as well as research settings.
Reported benefits
- Restores a more natural pulsatile GH release
- Improved sleep quality
- Gradual body composition support
- Favorable long-term safety record
How it works
Sermorelin binds pituitary GHRH receptors to stimulate the same natural, pulsatile GH release triggered by endogenous GHRH. Because the pituitary's own negative feedback loop, mediated by somatostatin and circulating IGF-1, remains intact, GH output is thought to self-limit in a way that exogenous GH administration does not.
Dosing ranges
| Tier | Dose | Frequency |
|---|---|---|
| Low | 200 mcg | once nightly |
| Moderate | 300 mcg | once nightly |
| High | 500 mcg | once or twice daily |
Estimate your dose
Dose estimator
Educational estimate for Sermorelin, scaled to body size. Not medical advice.
Read before using
This tool produces a rough, educational estimate by scaling commonly-published research ranges to lean body mass. It is not a prescription, medical advice, or a substitute for a licensed clinician. Most peptides use fixed dosing, not weight-based dosing. Individual needs vary. You are solely responsible for how you use this information.
Mixing & syringe units
Target dose follows the estimate above. Change it there, or edit it directly below.
Reconstitution calculator
How much water to add and how many insulin-syringe units to draw for Sermorelin. Educational only.
Draw to this mark
6units
= 0.06 mL for a 300 mcg dose
Concentration
5,000 mcg/mL
Doses per vial
33
A U-100 syringe reads 100 units per mL. This is a reconstitution math helper only, not a prescription or dosing advice. Verify every calculation and consult a qualified healthcare provider.
Possible side effects
Stacking notes
Sometimes combined with a GHRP for added pulse amplitude; also commonly used alone in physician-supervised anti-aging protocols.
Common protocols
Common questions
What is Sermorelin used for?
Sermorelin is a synthetic fragment of the first 29 amino acids of natural growth hormone releasing hormone (GHRH), retaining the full biological activity of the native hormone. It was previously marketed as an FDA-approved diagnostic and treatment agent (Geref) before being discontinued for commercial reasons, and it has a long clinical history in GH deficiency evaluation and pediatric treatment. Because it works through the pituitary's own GHRH receptors rather than replacing GH directly, it preserves natural feedback regulation, which is commonly cited as a safety advantage. It remains widely used in physician-supervised anti-aging and wellness protocols as well as research settings. Reported benefits include restores a more natural pulsatile gh release, improved sleep quality, gradual body composition support.
What is a typical Sermorelin dose?
Reported ranges run 200-500 mcg. A low protocol is 200 mcg once nightly, and a high protocol is 500 mcg once or twice daily. This is reference information, not a dosing recommendation.
What is the half life of Sermorelin?
~10-20 min. That is what sets the dosing frequency, and it is why the timing guidance is ~30 min before bed, empty stomach.
How is Sermorelin administered?
Subcutaneous: into fat, under the skin. Injected subcutaneously, typically before bed
How long is a Sermorelin cycle?
12 weeks on, followed by 4 weeks off. Some physician-supervised protocols use continuous dosing without scheduled breaks
What are the side effects of Sermorelin?
Reported side effects include injection-site redness, mild flushing, headache, uncommon dizziness. Evidence level for this compound is well studied.
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Educational use only, not medical advice. This profile is provided for research and educational purposes. Sermorelin may be a research compound or a prescription medication; nothing here is intended to diagnose, treat, cure, or prevent any disease. Dosing figures reflect commonly-published research ranges, not a prescription. Consult a qualified healthcare provider before making any health decision. Read the full disclaimer →