Sermorelin Dosing & Protocols — Research Reference

Sermorelin is the GHRH(1-29) fragment — the shortest sequence that retains full GHRH receptor activity. It is the most widely studied GHRH analogue and the historical reference compound for GH-pulse research.

Reconstitution for Research

Sermorelin is typically supplied lyophilized in 2 mg, 3 mg, 5 mg, or 15 mg vials. A 5 mg vial reconstituted with 2 mL bacteriostatic water yields 2.5 mg/mL; 10 IU on a U-100 syringe at 2.5 mg/mL delivers 250 mcg. Sermorelin is more pH-sensitive than longer-half-life GHRH analogues — keep refrigerated at 2–8 °C and use within the COA's documented window (typically 14–30 days reconstituted).

Reference Dose Ranges in Published Research

| Research model tier | Typical range | Notes | |---|---|---| | Entry / pulse characterization | 100–200 mcg per dose | Threshold for observable GH pulse in adult models | | Standard | 200–500 mcg per dose, once daily | Most cited; pre-sleep timing dominant | | High-dose pharmacology | 500–1000 mcg per dose | Used in acute pulse-amplitude studies |

Receptor desensitization plateaus the response above approximately 1 mcg/kg; further escalation does not proportionally increase GH output.

Scheduling

Sermorelin's ~10–20 minute half-life makes it a "pulse-preserving" GHRH analogue — it amplifies natural GH pulses rather than overriding them. Published research uses three timing patterns:

• Pre-sleep — leverages the nocturnal GH pulse (most cited).
• Fasted morning — minimizes somatostatin/insulin blunting.
• Post-exercise — captures the exercise-induced GH pulse.

Subcutaneous injection is the standard route. Once-daily pre-sleep dosing is the dominant protocol in long-duration research.

Synergistic Stacking with GHRPs

Sermorelin + a GHRP (ipamorelin, GHRP-2, hexarelin) is one of the most replicated stacks in GH-axis research. Typical pairing: 200–300 mcg sermorelin with 100–300 mcg ipamorelin per pulse, 1–3 times per day. The two receptor systems converge on cAMP/calcium signalling to produce synergistic GH release.

Cycling in the Published Literature

Long-duration GHRH exposure produces receptor downregulation in cellular and rodent models. Published cycling patterns run 12–16 weeks on with 4-week washout, or continuous conservative dosing with periodic stimulation-test verification.

Quality and Identity Verification

Mass-spec (LC-MS) confirmation of molecular weight (3357.93 Da) and HPLC purity ≥98% are the standard acceptance criteria. Endotoxin testing applies for parenteral animal models.

Research Use Only. All content is for laboratory research and educational reference. Compounds discussed are not intended for human or veterinary consumption, prophylactic, or therapeutic use.

References

1. Walker RF. Sermorelin: a better approach to management of adult-onset growth hormone insufficiency? Clin Interv Aging. 2006;1(4):307–308.
2. Khorram O, Laughlin GA, Yen SS. Endocrine and metabolic effects of long-term administration of [Nle27]growth hormone-releasing hormone-(1-29)-NH2 in age-advanced men and women. J Clin Endocrinol Metab. 1997;82(5):1472–1479.
3. Vance ML, Kaiser DL, Evans WS, et al. Pulsatile growth hormone secretion in normal man during a continuous 24-hour infusion of human growth hormone releasing factor (1-40). J Clin Invest. 1985;75(5):1584–1590.