Sermorelin
GHRH Analog · Growth Hormone Releasing Hormone
Sermorelin is a synthetic 29-amino acid analog of human growth hormone-releasing hormone that stimulates natural growth hormone production while preserving physiological pulsatile patterns. Originally FDA-approved in 1997 for pediatric GH deficiency, it was discontinued in 2008 for manufacturing reasons, not safety concerns.
Overview
Sermorelin is a synthetic 29-amino acid analog of human growth hormone-releasing hormone that stimulates natural growth hormone production while preserving physiological pulsatile patterns. Originally FDA-approved in 1997 for pediatric GH deficiency, it was discontinued in 2008 for manufacturing reasons, not safety concerns.
Subcutaneous injection provides optimal bioavailability for binding GHRH receptors, stimulating pulsatile GH release while maintaining hypothalamic-pituitary axis integrity and allowing natural somatostatin negative feedback.
Research indications
What the compound has been studied for, grouped by body system. Effect size is the reported magnitude where it was measured — not a recommendation.
1.26kg lean mass increase documented in elderly men with improved muscle strength tests.
Endogenous IGF-1 stimulation drives protein synthesis and muscle growth.
Enhanced recovery through physiological GH stimulation.
Doubles 12-hour GH release in elderly subjects over 6 weeks.
Decreased adiposity and improved lean mass distribution.
Improved skin thickness and quality.
Preserves natural axis function without suppression.
Maintains physiological GH release patterns.
A large effect in a weak study and a small effect in a strong one are different things. Effect size is never evidence of use in people.
- Class
- GHRH analog
- Chain length
- 29 residues
- Molecular weight
- 3358 Da
- Half-life
- ~11 min
- Typical dose
- 200-300mcg per dose (up to 500mcg for athletic performance)
- Frequency
- Once daily at bedtime (aligns with natural GH pulse)
- Cycle length
- 3-6 months continuous
- Storage
- Reconstituted: 2-8°C, use within 10-30 days
Molecular data
- Type
- GHRH analog
- Molecular weight
- 3358 Da
- Chain length
- 29 residues
- Half-life
- 11 min
Dosing reference
Doses reported in the literature and by suppliers. These are a record of what has been used in research — reference, never instruction.
| Context | Route | Amount | Frequency |
|---|---|---|---|
| Anti-aging/Longevity | SubQ | 200-300mcg | Once at bedtime |
| Athletic Performance | SubQ | 300-500mcg | Once at bedtime |
| Body Composition | SubQ | 200mcg | 5 days weekly |
| Combination Therapy | SubQ co-injection | 200mcg + GHRP | Once daily |
| Nasal administration | Nasal spray | 30+ mcg/kg | Once daily at bedtime |
Interactions
Excellent combination producing 3-5 fold increases in GH release.
Highly effective combination - CJC-1295 provides sustained 6-8 day release while sermorelin offers immediate pulsatile effects.
Combined GHRH+GHRP-2 produces 54-fold GH increases compared to 20-fold with GHRH alone.
Somatostatin analogs directly block GH release by activating inhibitory receptors.
High-dose glucocorticoids suppress pituitary GH release and reduce GHRH receptor sensitivity.
GH antagonizes insulin action; monitor combination closely.
Essential combination as untreated hypothyroidism prevents sermorelin response.
Quality checklist
- ✓Completely clear and colorless solution without particles, cloudiness, or precipitation
- ✓Greater than 98% peptide purity per USP standards
- ✓Sterile, nonpyrogenic lyophilized powder
- ✓Maintained at 2-8°C throughout transport
- ✓Produced in FDA-registered facilities following cGMP
- !Brief room temperature exposure acceptable up to 72 hours but should be refrigerated promptly
- ×Any cloudiness, particles, color changes, or precipitation indicates degradation
- ×Molecular weight should be exactly 3,358 daltons (free base) or 3,418 daltons (acetate salt)
What to expect
Safety
- Injection site reactions (16.7% of patients - generally mild)
- Nasal irritation (intranasal route)
- Signs of pituitary tumor growth (headaches, vision changes)
- Severe injection site reactions or generalized allergic responses
- Uncontrolled diabetes or significant glucose intolerance
- New onset or worsening malignancy symptoms
- Active malignancy
- Pituitary tumors
- Pregnancy
FAQ
Why was sermorelin discontinued if it was FDA-approved and safe?
Sermorelin was discontinued in 2008 for manufacturing reasons, not safety concerns. It was approved in 1997 and had a solid safety record, but the manufacturer stopped production. This left a gap in the market—sermorelin is now available through research/compounded sources but not as a branded pharmaceutical.
How does sermorelin preserve natural GH patterns better than taking GH directly?
Sermorelin stimulates your pituitary to release GH in its natural pulsatile pattern (high at night, low during day). Direct GH injection creates constant levels, suppressing your natural axis. Sermorelin preserves the hypothalamic-pituitary-axis (HPA) feedback loop, meaning you maintain natural regulation rather than becoming dependent on external hormones.
Why shouldn't I eat food 2+ hours before sermorelin injection?
Carbohydrates and high blood sugar suppress GH release. Eating before injection blunts your GH response by 50-80%, making the injection ineffective. Bedtime administration on an empty stomach ensures maximum GH secretion from the natural nocturnal pulse your body is primed to produce.
Can I combine sermorelin with GHRP-2 for even bigger GH increases?
Yes, and it's highly effective. GHRH + GHRP-2 combination produces 54-fold GH increases vs 20-fold with GHRH alone. However, start cautiously and monitor for joint pain/water retention. The synergy is excellent for body composition but requires more careful dose management than either alone.
References
- 1The effects of intranasal insufflation of growth hormone releasing factor analogue GRF 1-29 NH2 on growth hormone secretion in children with short statureLaron, Z., et al. · Clinical Endocrinology · 1988
Intranasal GRF 1-29 at 100mcg/kg induced prompt GH release in prepubertal children with peak values at 15 minutes. Demonstrated feasibility of nasal delivery with minimal side effects.
reviewPubMed 2877535 ↗ - 2Growth hormone (GH)-releasing hormone-(1-29) twice daily reverses the decreased GH and insulin-like growth factor-I levels in old menCorpas, E., et al. · Journal of Clinical Endocrinology & Metabolism · 1992
Landmark study in healthy old men (68 +/- 6.2 yr). High-dose GHRH(1-29) twice daily for 14 days reversed age-related decreases in GH and IGF-I to levels not significantly different from young men.
reviewPubMed 1379256 ↗ - 3Once daily subcutaneous growth hormone-releasing hormone therapy accelerates growth in growth hormone-deficient children during the first year of therapyGeref International Study Group · Journal of Clinical Endocrinology & Metabolism · 1996
Pivotal multicenter trial with 110 prepubertal GH-deficient children. Sermorelin 30mcg/kg/day at bedtime increased height velocity from 4.1 to 8.0 cm/year at 6 months, with 74% achieving good response.
reviewPubMed 8772599 ↗ - 4Endocrine and metabolic effects of long-term administration of [Nle27]growth hormone-releasing hormone-(1-29)-NH2 in age-advanced men and womenVittone, J., et al. · Journal of Clinical Endocrinology & Metabolism · 1997
5-month single-blind RCT in 19 adults (55-71 yr). Nightly GHRH analog for 4 months activated somatotropic axis. Men showed increased lean body mass, insulin sensitivity, and well-being. Skin thickness improved in both genders.
human-rctPubMed 9141536 ↗ - 5Sermorelin: a better approach to management of adult-onset growth hormone insufficiency?Walker, R.F. · Clinical Interventions in Aging · 2006
Review arguing sermorelin preserves pituitary function and physiological GH pulsatility, offering a safer alternative to exogenous GH for adult-onset GH insufficiency.
reviewPubMed 18046908 ↗