# Sermorelin Dosage in the Research Literature: GHRH(1-29) Doses, Routes, and Half-Life > Sermorelin dosage as studied in the literature — GHRH(1-29) doses by study and species, routes characterized, and the short ~10-12 minute plasma half-life. Research framing only, no human recommendations. The GHRH(1-29) doses, routes, and pharmacokinetics studies actually used — logged as study parameters, never as a recommendation to self-administer. ## Before the details This page reports the *sermorelin dosage* numbers used in published studies — which species, which dose, which route — and nothing more. It is not a protocol. Research-grade sermorelin is supplied as a lyophilized powder for laboratory study, and the figures below are study parameters, written in "studied at X in [population]" form. The key pharmacology fact to hold onto: sermorelin clears from the blood in minutes, yet a single dose can keep growth hormone elevated for about three hours — which is why studies dosed it the way they did. ## Doses used in the research literature The doses in the sermorelin record span pediatric efficacy, adult aging research, and pharmacokinetic characterization. None of the following is a human recommendation; each is a study parameter. - **Pediatric GH-deficiency efficacy:** 30 mcg/kg/day subcutaneously at bedtime in the multicenter pediatric trial [1]; long-term pediatric studies used 30 or 60 mcg/kg/day [10][26]. - **Aging research in older men:** 0.5 mg and 1 mg subcutaneously twice daily for 14 days, which produced dose-related GH and IGF-1 increases [2]. - **Adult somatotropic-axis activation:** 10 mcg/kg nightly for 16 weeks in age-advanced adults [25]. - **Pharmacokinetic / diagnostic:** intravenous doses of 0.25-2 mcg/kg elicited GH release in healthy men, with maximal release at 1-2 mcg/kg [3]. The consistent thread is dose-responsiveness: across routes, more GHRH(1-29) produced more GH, up to a plateau [3][11]. ## Half-life and pharmacokinetics Native sermorelin is short-lived. GHRH(1-29) has a plasma half-life on the order of about 10-12 minutes after intravenous administration and is rapidly eliminated — yet a single intravenous dose elevated serum GH for roughly 3 hours [3]. The hormone the peptide *triggers* outlasts the peptide itself. That brevity is the engineering problem the whole analogue family was built to solve. Incorporating D-Ala2 into GHRH(1-29)NH2 increased the peptide's half-life and decreased its metabolic clearance in normal men [17], and a review of PEGylation of GHRH (GRF) analogues catalogued chemical strategies to prolong the action of these short-lived peptides [8]. The long-acting DAC analogue CJC-1295 is the clinical expression of that same idea (see [sermorelin vs CJC-1295](/vs-cjc-1295)). ## Routes studied Three routes appear in the sermorelin literature, with markedly different efficiency. - **Subcutaneous** — the primary route in efficacy and aging studies [1][2][25]. - **Intravenous** — used in diagnostic GH-stimulation testing and pharmacokinetic work [3]. - **Intranasal** — characterized historically, but with bioavailability of only about 3-5% [3]. A dose-response study of the [Nle27]GHRH(1-29)-NH2 analogue across all three routes found a roughly tenfold higher subcutaneous and thirtyfold higher intranasal dose was required relative to intravenous to achieve comparable GH stimulation [11]. The poor mucosal absorption is also why oral, sublingual, and troche "sermorelin" formulations are widely criticized in research-user communities — peptides are degraded in the gut and poorly absorbed across mucosa. ## Formulation and stability Lyophilized sermorelin acetate is reconstituted with sterile diluent and, once in solution, typically refrigerated. Aqueous peptide solutions are susceptible to degradation, which is why GHRH(1-29) is supplied as a lyophilized powder rather than a ready-to-use liquid. In the compounding context, preparations are made under USP <797> sterile-compounding standards. For laboratory research material, the same handling logic applies: keep the powder dry and cold, reconstitute fresh, and treat the solution as perishable. None of this constitutes preparation guidance for human use. --- A soft control board of the sermorelin literature — every GHRH(1-29) finding pressed into its own lit module and wired back to its study, the confirmed pediatric result and the unsettled adult anti-aging gap kept on separate panels; no clinic behind the console and nothing here compounded, prescribed, or sold.