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The Peptide Effect
approvedGrowth Hormone

Sermorelin

Also known as: GRF 1-29, Geref, Sermorelin Acetate, GHRH(1-29)NH2

Sermorelin is a synthetic analog of the first 29 amino acids of growth hormone-releasing hormone (GHRH). It was previously FDA-approved under the brand name Geref for the diagnosis and treatment of growth hormone deficiency in children, though it has since been discontinued. It remains one of the most well-studied GHRH analogs used to stimulate natural growth hormone production from the pituitary gland.

Key Facts

Mechanism
Sermorelin binds to the GHRH receptor on somatotroph cells in the anterior pituitary gland, stimulating the synthesis and pulsatile release of endogenous growth hormone. Unlike exogenous HGH, it preserves the hypothalamic-pituitary feedback loop, maintaining natural GH secretion patterns including nocturnal pulses. This mechanism avoids the supraphysiological GH levels and negative feedback suppression associated with direct HGH administration.
Research Status
approved
Half-Life
~10–20 minutes
Molecular Formula
C₁₄₉H₂₄₆N₄₄O₄₂S
Primary Use
Growth Hormone

Benefits

  • Increases natural growth hormone production while preserving pulsatile release patternsstrong
  • Improves sleep quality and deepens slow-wave sleep phasesmoderate
  • Supports lean muscle mass development and maintenancemoderate
  • Enhances exercise recovery and tissue repair processesmoderate
  • May improve skin elasticity, thickness, and overall appearanceanecdotal
  • Promotes healthy body composition by supporting fat metabolismmoderate

Dosage Protocols

RouteDosage RangeFrequencyNotes
Subcutaneous injection200–300 mcgOnce daily at bedtimeBedtime dosing aligns with the natural nocturnal GH pulse and may enhance sleep-related GH release
Subcutaneous injection100–300 mcgOnce dailyGeneral daily protocol; administer on an empty stomach for best absorption
Subcutaneous injection100–200 mcgTwice daily (morning and bedtime)Split dosing protocol sometimes used in anti-aging clinics; fasting 1–2 hours before and after injection is recommended

Medical disclaimer

Dosage information is provided for educational reference only. Always follow your prescriber's instructions and consult a qualified healthcare provider before starting any peptide protocol.

Side Effects

  • Injection site reactions (redness, swelling, pain)common
  • Headachecommon
  • Facial flushing and warmth after injectioncommon
  • Difficulty swallowing (dysphagia)rare
  • Dizziness or lightheadedness shortly after administrationrare

Frequently Asked Questions

How is sermorelin different from HGH injections?
Sermorelin stimulates your pituitary gland to produce and release its own growth hormone naturally, preserving the pulsatile secretion pattern. HGH injections deliver synthetic growth hormone directly, bypassing the pituitary and potentially suppressing your body's natural GH production through negative feedback. Sermorelin is considered a more physiological approach with a lower risk of side effects associated with supraphysiological GH levels.
Can sermorelin help with age-related GH decline?
Yes. Growth hormone production naturally declines approximately 14% per decade after age 30 — a process called somatopause. Sermorelin can stimulate the pituitary to increase GH output, potentially counteracting some effects of this decline such as reduced lean mass, increased body fat, decreased energy, and impaired sleep quality. However, its effectiveness depends on the pituitary gland still being functional.
How long does it take to see results from sermorelin?
Most users report initial improvements in sleep quality within the first 2–4 weeks. Body composition changes (increased lean mass, reduced body fat) typically become noticeable after 3–6 months of consistent use. Full benefits related to skin, energy, and recovery generally emerge over a 6–12 month period. Individual responses vary based on age, baseline GH levels, and overall health.
Is sermorelin safe for the pituitary gland?
Sermorelin works with your body's natural feedback mechanisms rather than overriding them. Because it stimulates the pituitary through the normal GHRH receptor pathway, the hypothalamic-pituitary axis remains intact. The pituitary will not release more GH than it is capable of producing, providing a built-in safety mechanism against GH excess. This is a key advantage over exogenous HGH therapy.
What is the legal status of sermorelin?
Sermorelin was previously FDA-approved (brand name Geref) but has been voluntarily discontinued by its manufacturer. It is not a controlled substance in the United States and can be legally prescribed off-label by licensed physicians. It is commonly available through compounding pharmacies with a valid prescription. Its legal status varies by country, so international users should consult local regulations. This information is not legal advice.

References

  1. 1
    Growth hormone-releasing hormone: clinical studies and therapeutic aspects(1997)PubMed ↗
  2. 2
    Effects of growth hormone-releasing hormone on body composition in elderly subjects(1998)PubMed ↗
  3. 3
    Sermorelin: a review of its use in the diagnosis and treatment of children with idiopathic growth hormone deficiency(1999)PubMed ↗
  4. 4
    Growth hormone-releasing hormone in aging: relevance to the somatopause(2007)PubMed ↗

Last updated: 2026-02-14