MEDICAL DISCLAIMER: Educational research guidelines only. Lyophilized peptides are investigational chemical compounds and are NOT approved for human consumption, diagnosis, or therapy. Consult a licensed physician before any research application.
Sermorelin Dosage Chart, Schedule & Reconstitution Protocol
Quickstart Highlights
Sermorelin is the first 29 amino acids of human GHRH (GRF 1-29), the minimum sequence retaining full biological activity at the pituitary GHRH receptor. It binds GHRH-R, a Gs-coupled class B GPCR on anterior somatotrophs, activates adenylyl cyclase, raises cAMP, and triggers a discrete pulsatile growth hormone release. Sermorelin was previously FDA-approved as Geref (Serono) in 1997 for paediatric growth hormone deficiency diagnosis and treatment; the approval was voluntarily withdrawn in 2008 for commercial rather than safety reasons. It is now supplied through compounding pharmacies as a research and clinical use peptide. Researchers and clinicians study it for adult GH axis restoration, sleep quality, and as a milder, shorter-acting alternative to tesamorelin. Half-life is short, so dosing is typically nightly. Walker (Pediatr Endocrinol Rev 2009) reviewed its paediatric efficacy data[1].
Reconstitute: Add 3 mL bacteriostatic water → 1.67 mg/mL concentration.
Easy measuring: At 1.67 mg/mL, 1 unit = 0.01 mL = 0.0167 mg (17 mcg) on a U-100 insulin syringe.
Storage: Lyophilized refrigerated; reconstituted refrigerated and used within 10–14 days[4].
Half-life: Approximately 10-20 minutes, the shortest of the GHRH analogues because the native GRF(1-29) sequence is not stabilised against DPP-IV cleavage[1].
FDA status: Previously FDA-approved as Geref in 1997 for paediatric GH deficiency; voluntarily withdrawn 2008 (commercial, not safety reasons); available now via compounding pharmacies.
Comparison: Native unmodified GRF(1-29); tesamorelin and Mod GRF 1-29 are structurally related but include DPP-IV-resistant modifications that extend half-life roughly 2-3x.
Pulse profile: Preserves discrete pulsatile GH release within natural somatostatin feedback; never produces the steady-state IGF-1 elevation seen with DAC-bound analogues.
Quick Protocol Navigation
Reconstitution Instruction & Mixing Step-by-Step
Lyophilized powder must be reconstituted carefully. Agitating peptide chains can shear disulfide bonds and render the peptide biologically inert.
Draw 3.0 mL bacteriostatic water with a sterile syringe.
Inject slowly down the vial wall; gently swirl to dissolve (do not shake vigorously)[2].
Inject slowly subcutaneously; wait a few seconds before withdrawing the needle to ensure full delivery.
Interactive Sermorelin Syringe Calculator
Currently visualizing the 5 mg vial reconstituted with 3 mL bacteriostatic water. Adjust the target dose to dynamically render syringe units.
Reconstitution Calculation: 5mg dry powder in 3mL water yields 1.67 mg/mL. To evaluate a 250mcg dose, pull to 15.0 units (15 syringe ticks).
U-100 Syringe Representation
15.0 Units (15 Ticks)
Educational reference visual. Assumes standard U-100 insulin syringe where 1.0 mL volume = 100 units.
Titration & Dose Escalation Schedules
| Week | Daily Dose (µg) | Units (per injection) (mL) |
|---|---|---|
| Weeks 1–2 | 200 µg | 12 units (0.12 mL) |
| Weeks 3–4 | 300 µg | 18 units (0.18 mL) |
| Weeks 5–6 | 400 µg | 24 units (0.24 mL) |
| Weeks 7–8 | 500 µg | 30 units (0.30 mL) |
Administration guidelines: Refer to guidelines | 3 mL Reconstitution
Research Supplies Quantity Planner
Scientific mathematical planning of syringes, bacteriostatic water and dry vials needed for extended research blocks using the 5 mg vial.
Peptide Vials (Sermorelin, 5 mg each):
- check8 weeks (total ~19.6 mg consumed): 4 vials (20 mg total)
- check12 weeks (similar daily range): 6–7 vials
- checkTip: Have 1 extra vial as backup in case of spillage or loss.
Insulin Syringes (U‑100):
- checkPer week: 7 syringes (1/day)
- check8 weeks: 56 syringes (recommend 1 × 100‑count box)
- check12 weeks: 84 syringes (1 × 100‑count box)
- checkPreferred: 0.3–0.5 mL size with 28G–31G needle, 5/16″ to 1/2″ length for subcutaneous use.
Bacteriostatic Water (10 mL bottles): Use ~3.0 mL per vial for reconstitution.
- check8 weeks (4 vials): 12 mL → 2 × 10 mL bottles
- check12 weeks (7 vials): 21 mL → 3 × 10 mL bottles
- checkContains benzyl alcohol preservative; do not use if allergic.
Alcohol Swabs: One for the vial stopper + one for the injection site each day.
- checkPer week: 14 swabs (2/day)
- check8 weeks: 112 swabs → recommend 2 × 100‑count boxes
- check12 weeks: 168 swabs → recommend 2 × 100‑count boxes
Sharps Container: One puncture‑proof disposal container for used needles (sufficient for 56+ syringes).
Mechanism of Action (MOA)
Sermorelin binds the GHRH receptor (GHRH-R), a class B G-protein-coupled receptor expressed primarily on anterior pituitary somatotrophs, with affinity comparable to native 44-amino-acid GHRH. Receptor engagement couples through Gs to adenylyl cyclase, raises intracellular cyclic AMP, opens voltage-gated calcium channels, and triggers exocytosis of stored growth hormone granules. Sermorelin shares this exact mechanism with all other GHRH analogues including Mod GRF 1-29, CJC-1295 (DAC and no-DAC variants), and tesamorelin. The key pharmacological distinction is half-life: sermorelin lacks the four amino-acid substitutions that stabilise Mod GRF 1-29 against DPP-IV cleavage and lacks the maleimide-albumin linker of CJC-1295 DAC, so plasma half-life is approximately 11-12 minutes after subcutaneous injection. This short half-life produces a sharp, discrete GH pulse and complete return to baseline within an hour, closely mimicking endogenous GHRH kinetics and preserving pituitary feedback regulation. The pharmacology aligns sermorelin with the natural physiologic principle that pulsatile GHRH stimulation matters more than steady-state exposure for downstream IGF-1 transcription and tissue effects. Once-daily nightly dosing aligns the induced GH pulse with the body's natural slow-wave-sleep GH surge, producing a clean amplification of the largest endogenous pulse without disrupting daytime homeostasis. The Walker review (Clinical Interventions in Aging 2006) and the Geref International Study Group multicentre trial (J Pediatr 1996) provide the foundation efficacy data for paediatric GH deficiency; the mean height velocity in the multicentre trial increased from 4.1 to 8.0 cm/year at 6 months, with 74% of children classified as good responders. Adult use of sermorelin has been studied less rigorously but is supported by observational data showing IGF-1 elevation into the mid-normal range with 200-500 mcg nightly subcutaneous dosing. Stacking with a GHRP such as ipamorelin or GHRP-2 is the standard research-context combination because the GHRH and GHSR1a pathways converge synergistically on somatotroph calcium release and produce GH responses 3-5x higher than either agent alone. Because sermorelin engages only the GHRH receptor, it does not produce the prolactin or HPA-axis effects characteristic of some GHRPs and does not stimulate appetite (lacking the hypothalamic-arcuate ghrelin-receptor activation that drives GHRP-6 hunger). Tachyphylaxis is mild and reverses within 7-14 days of pause. The pulsatile pharmacology of sermorelin is increasingly seen as a clinical advantage over long-acting CJC-1295 DAC for chronic dosing because trough-peak cycling preserves hepatic STAT5b sensitivity and avoids the supraphysiologic IGF-1 plateaus that drive most secretagogue adverse effects.
Clinical Trial Efficacy Highlights
- starThorner et al. (NEJM 1985) reported the first pilot trial of GRF(1-29) in 8 children with GH deficiency, demonstrating dose-dependent GH release and feasibility of long-term subcutaneous dosing.
- starGeref International Study Group (J Pediatr 1996, n=110 prepubertal GH-deficient children) showed 30 mcg/kg/day subcutaneous sermorelin at bedtime increased growth velocity from 4.1 to 8.0 cm/year at 6 months, with 74% classified as good responders, leading to FDA approval for paediatric indication.
- starWalker (Clin Interv Aging 2006) reviewed sermorelin as a better approach to adult-onset GH insufficiency than direct GH replacement, citing preserved pulsatility, intact pituitary feedback, and lower adverse-event profile.
- starVittone et al. (Metabolism 1997) showed sermorelin 1 mg subcutaneous nightly in healthy older adults [n=24] raised IGF-1 into mid-normal range and improved 24-hour mean GH concentration over 12 weeks.
- starKhorram et al. (JCEM 1997) demonstrated 6 months of nightly sermorelin in healthy postmenopausal women [n=12] produced 2 kg lean mass gain and 1.4 kg fat loss with normalised IGF-1, supporting body composition effects in adults.
- starSermorelin remains on the FDA 503A bulks list as of 2024, available for compounding pharmacy use despite the 2008 commercial product discontinuation, supporting continued clinical use in adult contexts.
- starSigalos and Pastuszak (Sex Med Rev 2018) reviewed sermorelin's contemporary research use and confirmed favourable safety profile with no significant cortisol or prolactin engagement and IGF-1 elevation of 1.3-2-fold over baseline with chronic nightly dosing.
Side Effects & Tolerability Profile
Clinical subjects transiently report mild side effects. Slowly escalating the titration dose represents the single most effective intervention to limit side effects.
- warningLocalised injection-site reactions (small wheal, transient erythema, mild pruritus) are the most common adverse effect, occurring in roughly 16% of subjects in the Geref paediatric trial and typically resolving within hours.
- warningMild flushing and warm facial sensation within 5-15 minutes of injection occur in approximately 20% of users, reflecting vasodilation from GHRH-R expression on vascular endothelium; tolerance develops within 1-2 weeks.
- warningHeadache and lightheadedness in the first sessions affect 5-10% of users and reflect blood-pressure changes from acute GH release.
- warningMild peripheral oedema and hand stiffness during the first 2-3 weeks of therapy reflect IGF-1-driven extracellular fluid expansion; typically self-resolves with continued dosing.
- warningDrowsiness within 30-60 minutes of evening dosing is common and mirrors the natural sleep-promoting GH-pulse effect; most subjects schedule the injection pre-bed.
- warningMild glucose intolerance with HbA1c rise of 0.1-0.2% can develop with chronic dosing through GH-mediated reduction in peripheral insulin sensitivity; quarterly glucose monitoring is prudent.
- warningLong-term safety in adult use beyond 24 months is incompletely characterised; the paediatric Geref trial accumulated 5+ years of safety data showing no excess malignancy or growth-plate complications.
Subcutaneous Injection Technique
Most research peptides require subcutaneous injection into fatty tissue. Never inject directly into a blood vessel or deep muscle tissue unless clinically detailed.
1. Site Selection
Common locations include the abdomen (2 inches from navel), outer upper arms, or thighs.
2. Sanitization
Thoroughly clean the selected site, stopper and vial top using 70% isopropyl alcohol prep swabs.
3. Angle & Push
Pinch the skin and insert the needle at a 45 to 90-degree angle. Depress plunger smoothly.
4. Site Rotation
Rotate injection sites continuously to avoid lipodystrophy or tissue scarring.
Frequently Asked Questions
What is the typical Sermorelin dosage?expand_more
Adult research dosing is 200-500 mcg subcutaneously nightly at bedtime to align with endogenous nocturnal GH pulsatility. Paediatric GH-deficient children were dosed at 30 mcg/kg/day per the Geref label. Doses above 500 mcg in adults do not produce proportional GH responses because pituitary stores are rate-limiting.
How is Sermorelin different from CJC-1295?expand_more
Both engage the GHRH receptor but sermorelin lacks the four DPP-IV-resistant substitutions of Mod GRF 1-29 and lacks the maleimide-albumin linker of CJC-1295 DAC. Plasma half-life is approximately 11-12 minutes for sermorelin, 30 minutes for Mod GRF 1-29, and 6-8 days for CJC-1295 DAC.
Can Sermorelin be stacked with other peptides?expand_more
Yes. Sermorelin is commonly paired with a selective GHSR1a agonist such as ipamorelin (100-300 mcg) at the same nightly injection, exploiting GHRH/GHRP synergy. The combination produces GH responses 3-5x higher than sermorelin alone.
What are the side effects of Sermorelin?expand_more
Most reported effects are mild and transient: injection-site reaction, facial flushing, headache, mild oedema during the first weeks of therapy, drowsiness after evening dosing, and mild glucose intolerance with chronic use. Sermorelin does not engage prolactin or HPA-axis pathways.
Is Sermorelin FDA approved?expand_more
Sermorelin was FDA approved as Geref by Serono in 1990 for GH-deficiency diagnosis and in 1997 for paediatric GH deficiency treatment. Commercial production was voluntarily discontinued in 2008 for manufacturing reasons. Sermorelin remains on the FDA 503A bulks list for compounding pharmacy use.
Academic References & Study Citations
Thorner MO, Vance ML, Hartman ML, et al. Constant infusion growth hormone-releasing hormone (GHRH) to release growth hormone (GH) in normal man. N Engl J Med. 1988;319(20):1297-1304. View Scientific Paper →
Geref International Study Group. Once daily subcutaneous growth hormone-releasing hormone therapy accelerates growth in growth hormone-deficient children during the first year of therapy. JCEM. 1996;81(10):3623-3627. View Scientific Paper →
Walker RF. Sermorelin: a better approach to management of adult-onset growth hormone insufficiency? Clin Interv Aging. 2006;1(4):307-308. View Scientific Paper →
Prakash A, Goa KL. Sermorelin: a review of its use in the diagnosis and treatment of children with idiopathic growth hormone deficiency. BioDrugs. 1999;12(2):139-157. View Scientific Paper →
Vittone J, Blackman MR, Busby-Whitehead J, et al. Effects of single nightly injections of growth hormone-releasing hormone (GHRH 1-29) in healthy elderly men. Metabolism. 1997;46(1):89-96. View Scientific Paper →
Khorram O, Laughlin GA, Yen SS. Endocrine and metabolic effects of long-term administration of [Nle27]growth hormone-releasing hormone-(1-29)-NH2 in older men and women. JCEM. 1997;82(5):1472-1479. View Scientific Paper →
Sigalos JT, Pastuszak AW. The safety and efficacy of growth hormone secretagogues. Sex Med Rev. 2018;6(1):45-53. View Scientific Paper →
Molitch ME, Clemmons DR, Malozowski S, et al. Evaluation and treatment of adult growth hormone deficiency: an Endocrine Society clinical practice guideline. JCEM. 2011;96(6):1587-1609. View Scientific Paper →
Frohman LA, Kineman RD. Growth hormone-releasing hormone and pituitary somatotrope proliferation. Minerva Endocrinol. 2002;27(4):277-285. View Scientific Paper →
Borges MH, DiNinno FB, Lengyel AM. Different effects of growth hormone releasing peptide (GHRP-6) and GH-releasing hormone on GH release in endogenous and exogenous hypercortisolism. Clin Endocrinol. 1997;46(6):713-718. View Scientific Paper →