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.
Relamorelin Dosage Chart, Schedule & Reconstitution Protocol
Quickstart Highlights
Relamorelin (RM-131) is a synthetic pentapeptide ghrelin/GHSR-1a receptor agonist developed as a gastrointestinal prokinetic for diabetic gastroparesis and chronic constipation. It is a stabilized ghrelin analog with about six-fold greater receptor potency and a much longer half-life than native ghrelin, and it accelerates gastric emptying and gut motility through vagal and enteric pathways (PMID 25545036, 27055601). The route really is subcutaneous, matching the reconstitution model on this page. The most-studied dosing is 10 to 100 mcg subcutaneously once or twice daily, with 10-30 mcg twice daily proving effective and better tolerated and 30 mcg twice daily often treated as optimal; 100 mcg added glycemic side effects (PMID 28760384). Relamorelin is investigational: its phase 3 program was terminated in 2020 and it is not approved by the FDA or EMA, so this is educational reference content only, not medical advice.
Reconstitute: Add 2 mL bacteriostatic water → 0.5 mg/mL concentration.
Typical dose: 10-30 mcg SC twice daily (up to 100 mcg studied)
Easy measuring: At 0.5 mg/mL, 1 unit = 0.01 mL = 0.0050 mg (5 mcg) on a U-100 insulin syringe.
Storage: Lyophilized powder stored frozen at −20 °C and protected from light. Once reconstituted, the solution should be refrigerated at 2-8 °C and used within roughly 2-4 weeks. Do not freeze the reconstituted solution and avoid prolonged warming or vigorous agitation.
Half-life: Approximately 4.5 hours at typical doses (up to ~19 hours at the highest doses); Tmax near 0.7 hour
Route: Subcutaneous injection, once or twice daily (the genuine clinical route)
Status: Investigational; not FDA- or EMA-approved; phase 3 gastroparesis program terminated in 2020
About Relamorelin
Relamorelin (RM-131) is a synthetic pentapeptide ghrelin-receptor (GHSR-1a) agonist engineered as a gastrointestinal prokinetic, with about six-fold greater potency and far better plasma stability than native ghrelin [1]. Unlike oral or topical compounds on this site, relamorelin's clinical route genuinely is subcutaneous injection, so the figures below reflect how it was actually dosed in phase 2 trials rather than an educational conversion.\n\nAcross published studies the Relamorelin dosage ranged from 10 to 100 micrograms given once or twice daily; the dose-ranging BLOOM-DM trial used 10, 30 and 100 mcg twice daily, and the 10-30 mcg twice-daily band proved both effective for symptoms and gastric emptying and better tolerated, while 100 mcg added glycemic side effects [3][4]. The 30 mcg twice-daily dose is frequently cited as the optimal balance.\n\nThis guide models a 1 mg (1000 mcg) vial reconstituted with 2 mL of bacteriostatic water, yielding 500 mcg/mL so doses fall on a U-100 insulin syringe: 10 mcg ≈ 2 units (0.02 mL), 30 mcg ≈ 6 units (0.06 mL), and 100 mcg ≈ 20 units (0.20 mL). Because doses are micrograms, draw slowly and read the plunger carefully.\n\nFrequency: Twice daily subcutaneously, classically about 30 minutes before breakfast and the evening meal; phase 2a also tested a single morning dose. Relamorelin is investigational and is NOT approved by the FDA or EMA; this page is an educational reference only, not medical advice [7][8].
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 2 mL of bacteriostatic water into a sterile syringe.
Inject the water slowly down the inner glass wall of the 1 mg (1000 mcg) relamorelin vial; do not spray it directly onto the lyophilized powder, and never shake.
Gently swirl or roll the vial until fully clear; this yields a 500 mcg/mL solution, equal to 5 mcg per insulin-syringe unit (so 10 mcg = 2 units, 30 mcg = 6 units, 100 mcg = 20 units).
Store the reconstituted vial refrigerated at 2-8 °C, protected from light, and use within roughly 2-4 weeks; swab the stopper with alcohol before each draw.
Inject subcutaneously into the abdomen or thigh; because microgram doses are tiny volumes, draw slowly, expel air bubbles, and verify the plunger position against the unit marks before injecting.
Interactive Relamorelin Syringe Calculator
Currently visualizing the 1 mg vial reconstituted with 2 mL bacteriostatic water. Adjust the target dose to dynamically render syringe units.
Reconstitution Calculation: 1mg dry powder in 2mL water yields 0.50 mg/mL. To evaluate a 250mcg dose, pull to 50.0 units (50 syringe ticks).
U-100 Syringe Representation
Educational reference visual. Assumes standard U-100 insulin syringe where 1.0 mL volume = 100 units.
Titration & Dose Escalation Schedules
| Phase | Dose per injection | Units (per injection) |
|---|---|---|
| Weeks 1-2 — lowest studied dose / titration start | 10 mcg | 2 units (0.02 mL) |
| Weeks 3+ — optimal symptom dose (BLOOM-DM) | 30 mcg | 6 units (0.06 mL) |
| Upper dose-range ceiling studied (more glycemic effects) | 100 mcg | 20 units (0.20 mL) |
Administration guidelines: Refer to guidelines | 2 mL Reconstitution
Research Supplies Quantity Planner
Scientific mathematical planning of syringes, bacteriostatic water and dry vials needed for extended research blocks using the 1 mg vial.
Peptide Vials (Relamorelin, 1 mg each):
- check8 weeks at 10 mcg twice daily (20 mcg/day) ≈ 1,120 mcg ≈ 2 vials
- check12 weeks at 30 mcg twice daily (60 mcg/day) ≈ 5,040 mcg ≈ 6 vials
- check16 weeks at 100 mcg twice daily (200 mcg/day) ≈ 22,400 mcg ≈ 23 vials — the high count illustrates why low doses were preferred
Insulin Syringes (U-100):
- checkTwice-daily dosing: 14 syringes per week
- check8 weeks ≈ 112 syringes; 12 weeks ≈ 168 syringes; 16 weeks ≈ 224 syringes
- checkUse a fresh syringe per injection; microgram doses (2-20 units) demand careful plunger reading
Bacteriostatic Water (30 mL bottles): Use 2 mL per 1 mg vial for reconstitution.
- check8 weeks (~2 vials) ≈ 4 mL ≈ 1 bottle
- check12 weeks (~6 vials) ≈ 12 mL ≈ 1 bottle
- check16 weeks (~23 vials) ≈ 46 mL ≈ 2 bottles
Alcohol Swabs:
- check1-2 swabs per injection (vial stopper + injection site), twice daily
- check8 weeks ≈ 112-224 swabs; 12 weeks ≈ 168-336 swabs
- check16 weeks ≈ 224-448 swabs; keep extras for re-swabbing the multi-use vial
Mechanism of Action (MOA)
Relamorelin (RM-131) is a synthetic pentapeptide analog of ghrelin (molecular weight ~791 Da; CAS 661472-41-9) carrying non-natural amino-acid substitutions that block the enzymatic cleavage and de-acylation that rapidly inactivate native ghrelin. The result is a full agonist of the growth hormone secretagogue receptor type 1a (GHSR-1a, the ghrelin receptor) with roughly six-fold greater potency than ghrelin itself and markedly improved plasma stability [1]. Although it shares ghrelin's endocrine signature, relamorelin was optimized as a gastrocolokinetic (gut-motility) agent rather than a growth-hormone drug.\n\nGHSR-1a is expressed on hypothalamic and pituitary neurons but also densely on vagal afferent fibers, the enteric nervous system, and gastric smooth muscle. By activating these receptors, relamorelin increases vagal-cholinergic drive to the stomach, augments antral contractility and antroduodenal coordination, and accelerates gastric emptying of solids; it also stimulates colonic motility and transit, which underlies its testing in chronic constipation [1][5]. In type 1 diabetic patients a single 100 mcg subcutaneous dose cut the gastric-emptying half-time of solids by roughly half versus placebo [2], and in dose-ranging gastroparesis trials 10-30 mcg twice daily significantly accelerated emptying compared with placebo [4].\n\nPharmacokinetics: relamorelin is given subcutaneously and absorbed rapidly, with a median time to peak concentration (Tmax) near 0.7 hour. The elimination half-life is approximately 4.5 hours at typical doses, lengthening to as much as ~19 hours at the highest doses studied; exposure (AUC) is dose-proportional with no meaningful accumulation over 10 days of repeated dosing. It is highly protein-bound (~83-96%), undergoes little or no detectable hepatic metabolism, and only about 8% is recovered in urine, suggesting clearance is largely non-renal and non-hepatic [1]. The short-to-moderate half-life supports the once- or twice-daily regimens used in trials.\n\nBecause GHSR-1a is the same receptor that drives appetite and the GH axis, relamorelin produces predictable on-target endocrine effects: transient rises in plasma growth hormone, prolactin, and cortisol, and stimulation of appetite. Clinically, the most important on-target liability is dose-dependent worsening of glycemic control: in diabetic patients, higher doses raised fasting glucose and HbA1c, presumably via GH-mediated insulin resistance and possibly faster glucose delivery from accelerated emptying [4][6]. This is why the 10-30 mcg twice-daily range was favored over 100 mcg.\n\nDevelopment status: relamorelin reached phase 3 for diabetic gastroparesis (the Allergan/AbbVie PLEDGE program) and held FDA Fast Track designation, but those pivotal trials were terminated in 2020 as a stated business decision; it has never been approved by the FDA or EMA and remains an investigational compound [7][8]. The protocol on this page is an educational reference, not a validated treatment regimen or medical advice.
Clinical Trial Efficacy Highlights
- starShin, Camilleri and colleagues (2013, Clinical Gastroenterology and Hepatology) gave a single 100 mcg subcutaneous dose of RM-131 to patients with type 1 diabetes mellitus in a double-blind crossover study and observed roughly a 55% improvement in the gastric-emptying half-time of solids versus placebo, alongside reduced upper-GI symptoms, providing early proof that ghrelin-receptor agonism accelerates emptying in diabetic gastric dysmotility [2].
- starLembo and colleagues (2016, Gastroenterology) reported the phase 2a trial: 204 adults with diabetic gastroparesis were randomized to placebo or 10 mcg subcutaneous relamorelin once or twice daily for 28 days; twice-daily relamorelin significantly accelerated gastric emptying and, in the subgroup with baseline vomiting, reduced vomiting frequency and core symptoms (nausea, abdominal pain, bloating, early satiety) compared with placebo [3].
- starCamilleri and colleagues (2017, Gastroenterology) conducted the pivotal phase 2b BLOOM-DM trial in 393 patients, randomizing to placebo or relamorelin 10, 30, or 100 mcg twice daily for 12 weeks; all three doses significantly reduced the four cardinal gastroparesis symptoms and the composite score versus placebo, and the 10 and 30 mcg doses significantly accelerated gastric emptying, establishing the lower-dose range as the efficacious, better-tolerated window [4].
- starVomiting frequency fell by roughly 75% from baseline across all relamorelin arms in BLOOM-DM, but an unusually large placebo response (~70% reduction) prevented statistical separation on that single endpoint, underscoring the difficulty of demonstrating antiemetic benefit in gastroparesis trials [4].
- starAcosta, Camilleri and colleagues (2015, Clinical Gastroenterology and Hepatology) showed in a phase 2 randomized, placebo-controlled trial that relamorelin relieved symptoms of chronic constipation and accelerated colonic transit, demonstrating that the drug acts as a true gastrocolokinetic agent throughout the gut rather than only on the stomach [5].
- starCamilleri and Acosta's mechanistic review (2015, Neurogastroenterology & Motility) summarized that relamorelin activates GHSR-1a with about six-fold greater potency than native ghrelin, is rapidly absorbed subcutaneously (Tmax ~0.7 h) with a ~4.5 h half-life, shows dose-proportional exposure without accumulation, and reliably accelerates gastric emptying in type 1 and type 2 diabetes [1].
- starA pooled safety analysis of the phase 2a and 2b programs (Camilleri et al., 2020, Alimentary Pharmacology & Therapeutics; 597 patients) confirmed relamorelin 10-100 mcg was generally well tolerated, with the principal dose-related signal being worsening glycemic control (higher fasting glucose and HbA1c), supporting use of the lowest effective dose in any diabetic population [6].
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.
- warningDose-dependent worsening of glycemic control is the most important effect: higher relamorelin doses raised fasting blood glucose and HbA1c in diabetic patients, with about 14.5% showing hyperglycemia on drug and some needing diabetes-medication adjustment; close glucose monitoring is essential and the 100 mcg twice-daily dose was the worst offender [4][6].
- warningHyperhidrosis (excessive sweating) is a characteristic on-target adverse effect of ghrelin-receptor activation reported in relamorelin trials [6].
- warningGastrointestinal effects such as diarrhea and abdominal cramping occurred dose-dependently, consistent with the drug's pro-motility action on the stomach and colon [4][6].
- warningAppetite stimulation and weight gain can occur because GHSR-1a is the central hunger receptor; transient rises in growth hormone, prolactin, and cortisol are expected on-target endocrine effects [1].
- warningDizziness, fatigue, and headache were reported, generally mild and more common at higher doses [6].
- warningAcross the pooled phase 2 program no consistent drug-related serious cardiovascular signal emerged, but isolated serious events (unstable angina, diabetic ketoacidosis, one unrelated death from urosepsis) were recorded in this medically complex diabetic population; people with cardiac or poorly controlled diabetic disease warrant caution [6].
- warningSafety beyond 12 weeks, in pregnancy, in lactation, and in non-diabetic healthy users is not established; appropriate contraindications and long-term risks remain undefined because development stopped at phase 3.
- warningRegulatory/research status: relamorelin is NOT approved by the FDA or EMA; its phase 3 diabetic-gastroparesis program was terminated in 2020, and it is an investigational compound presented for educational purposes only, not for human therapeutic use [7][8].
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 Relamorelin dosage?expand_more
In published human trials the Relamorelin dosage ranged from 10 to 100 micrograms given subcutaneously once or twice daily. The pivotal phase 2b BLOOM-DM study compared 10, 30, and 100 mcg twice daily; the 10-30 mcg twice-daily range was both effective for gastroparesis symptoms and accelerating gastric emptying and better tolerated, while 100 mcg added glycemic side effects without clear extra benefit. The 30 mcg twice-daily dose is frequently cited as optimal. Note relamorelin is investigational and not approved for use; these figures are an educational reference, not a prescribing recommendation.
Is Relamorelin FDA approved?expand_more
No. Relamorelin (RM-131) is not approved by the FDA or the EMA for any indication. It advanced to phase 3 for diabetic gastroparesis under Allergan/AbbVie (the PLEDGE program) and held FDA Fast Track designation, but those pivotal trials were terminated in 2020 as a stated business decision. It remains an investigational compound, and this page is provided for educational purposes only, not as medical advice.
How do you reconstitute Relamorelin?expand_more
This guide models a 1 mg (1000 mcg) vial reconstituted with 2 mL of bacteriostatic water, giving a 500 mcg/mL solution, or 5 mcg per insulin-syringe unit. Inject the water slowly down the vial wall, swirl gently without shaking until clear, then refrigerate at 2-8 °C and use within about 2-4 weeks. On a U-100 syringe, 10 mcg is 2 units, 30 mcg is 6 units, and 100 mcg is 20 units. Because doses are in micrograms, draw slowly and read the unit marks carefully.
What is the half life of Relamorelin?expand_more
Relamorelin has an elimination half-life of approximately 4.5 hours at typical subcutaneous doses, which lengthens to as much as roughly 19 hours at the highest doses studied. It is absorbed quickly, with peak plasma levels (Tmax) near 0.7 hour. Exposure is dose-proportional with no meaningful accumulation over 10 days of repeated dosing, which supports once- or twice-daily administration.
What are the main Relamorelin side effects?expand_more
The most notable side effect is dose-dependent worsening of glycemic control (higher fasting glucose and HbA1c) in diabetic patients, which is why lower doses are favored. Other reported effects include hyperhidrosis (sweating), diarrhea and abdominal cramping from increased gut motility, appetite stimulation, transient rises in growth hormone/prolactin/cortisol, and mild dizziness, fatigue, or headache. Anyone with diabetes considering it would need close glucose monitoring; long-term safety is not established and the compound is investigational only.
Related Guides & Tools
Step-by-step references for reconstituting, measuring, and storing Relamorelin, plus the universal dosing calculator.
Academic References & Study Citations
Camilleri M, Acosta A. Emerging treatments in neurogastroenterology: relamorelin: a novel gastrocolokinetic synthetic ghrelin agonist. Neurogastroenterol Motil. 2015;27(3):324-332. View Scientific Paper →
Shin A, Camilleri M, Busciglio I, et al. The ghrelin agonist RM-131 accelerates gastric emptying of solids and reduces symptoms in patients with type 1 diabetes mellitus. Clin Gastroenterol Hepatol. 2013;11(11):1453-1459.e4. View Scientific Paper →
Lembo A, Camilleri M, McCallum R, et al. Relamorelin reduces vomiting frequency and severity and accelerates gastric emptying in adults with diabetic gastroparesis. Gastroenterology. 2016;151(1):87-96.e6. View Scientific Paper →
Camilleri M, McCallum RW, Tack J, Spence SC, Gottesdiener K, Fiedorek FT. Efficacy and safety of relamorelin in diabetics with symptoms of gastroparesis: a randomized, placebo-controlled study. Gastroenterology. 2017;153(5):1240-1250.e2. View Scientific Paper →
Acosta A, Camilleri M, Kolar G, et al. Relamorelin relieves constipation and accelerates colonic transit in a phase 2, placebo-controlled, randomized trial. Clin Gastroenterol Hepatol. 2015;13(13):2312-2319.e1. View Scientific Paper →
Camilleri M, Lembo A, McCallum R, et al. Overall safety of relamorelin in adults with diabetic gastroparesis: analysis of phase 2a and 2b trial data. Aliment Pharmacol Ther. 2020;51(11):1139-1148. View Scientific Paper →
Allergan plc. Allergan expands PLEDGE clinical research program in diabetic gastroparesis (relamorelin phase 3). Press release, May 17, 2019. View Scientific Paper →
ClinicalTrials.gov. A Safety and Efficacy Study of Relamorelin in Diabetic Gastroparesis (NCT03285308). U.S. National Library of Medicine (phase 3 program, terminated 2020). View Scientific Paper →