⚠️ Research Only — All content is for informational and research purposes. Not medical advice. Read full disclaimer

Anamorelin

Also known as: RC-1291, ONO-7643

Anamorelin is a synthetic ghrelin receptor agonist that stimulates growth hormone release and increases appetite through activation of the growth hormone secretagogue receptor.

Last updated: February 14, 2026Reviewed by: Peptide Research Team

Anamorelin is a 325.4 g/mol research peptide. Anamorelin is a synthetic ghrelin receptor agonist that stimulates growth hormone release and increases appetite through activation of the growth hormone secretagogue receptor.

Also called: RC-1291, ONO-7643

325.4 g/mol

Molecular Weight

Daltons

2

Strong Evidence

benefits

4

Studies Cited

peer-reviewed

50-100

Typical Dose

mg

Overview

Anamorelin functions as a potent and selective ghrelin receptor agonist, specifically targeting the growth hormone secretagogue receptor 1a (GHSR1a). This peptide mimics the action of endogenous ghrelin by binding to receptors in the hypothalamus and pituitary gland, triggering the release of growth hormone and stimulating appetite centers in the brain. Research demonstrates anamorelin's dual mechanism involves both central nervous system pathways that regulate hunger and the hypothalamic-pituitary-growth hormone axis. Studies show the compound increases food intake, body weight, and lean body mass while maintaining favorable safety profiles in various research models. The peptide has undergone extensive clinical investigation for conditions involving muscle wasting, appetite loss, and growth hormone deficiency.

Key Takeaways: Anamorelin

  • Strongest evidence supports Anamorelin for growth hormone stimulation and appetite enhancement
  • Research doses typically range from 50 to 100 mg via oral
  • 2 benefits with strong evidence, 3 moderate, 1 preliminary
  • Half-life: 5-7 hours
  • 4 cited research studies in this guide

Mechanism of Action

Anamorelin binds to and activates the growth hormone secretagogue receptor 1a (GHSR1a) in the hypothalamus and pituitary gland. This activation stimulates the release of growth hormone from somatotroph cells while simultaneously activating neuropeptide Y (NPY) and agouti-related protein (AgRP) neurons in the arcuate nucleus, leading to increased appetite and food intake. The compound also influences insulin-like growth factor-1 (IGF-1) production and may affect ghrelin-responsive pathways involved in energy homeostasis and metabolism.

Research Benefits

Anamorelin at a Glance

Primary mechanism:

Anamorelin binds to and activates the growth hormone secretagogue receptor 1a (GHSR1a) in the hypothalamus and pituitary gland.

Top researched benefits:
Growth Hormone StimulationAppetite EnhancementLean Body Mass PreservationWeight Gain SupportMetabolic FunctionBone Health Support

Growth Hormone Stimulation

Strong Evidence

Activates GHSR1a receptors to promote pulsatile growth hormone release, with studies showing 2-3 fold increases in GH levels within 1-2 hours of administration.

Appetite Enhancement

Strong Evidence

Stimulates hypothalamic appetite centers through NPY and AgRP neuron activation, leading to significant increases in food intake and caloric consumption in research models.

Lean Body Mass Preservation

Moderate Evidence

Promotes protein synthesis and muscle preservation through growth hormone-mediated pathways, particularly beneficial in conditions involving muscle wasting or catabolism.

Weight Gain Support

Moderate Evidence

Facilitates healthy weight gain through combined appetite stimulation and anabolic effects, with research showing sustained weight increases over treatment periods.

Metabolic Function

Moderate Evidence

Influences glucose homeostasis and lipid metabolism through growth hormone and IGF-1 pathways, potentially improving overall metabolic efficiency.

Bone Health Support

Preliminary

May support bone formation and mineralization through growth hormone-stimulated IGF-1 production and direct effects on osteoblast activity.

Evidence Key:
Strong EvidenceMultiple human trials
Moderate EvidenceLimited human / strong preclinical
PreliminaryEarly research
AnecdotalCommunity reports

Research Dosing Protocols

Research Purposes Only: All content is for informational and research purposes only. This site does not provide medical advice, diagnosis, or treatment. Consult a qualified healthcare professional before using any peptide or supplement.

Research ProtocolDose RangeRoute
Growth hormone stimulation50100 mgoral
Appetite enhancement research2575 mgoral

Frequency

Once daily

Timing

30-60 minutes before meals, typically in the evening

Cycle Length

4-12 weeks

Research Notes

  • 1Oral administration is preferred due to high bioavailability
  • 2Evening dosing may optimize natural growth hormone patterns
  • 3Effects on appetite typically observed within 1-3 days
  • 4Growth hormone responses peak 1-2 hours post-administration
  • 5Research protocols often include 1-2 week washout periods

Reconstitution Guide

Standard Reconstitution

Vial Size

25 mg

Bacteriostatic Water

2.5 mL

Concentration

100 mcg

per 0.1 mL (10 units)

Step-by-Step Guide

1

Gather Materials

Anamorelin vial, bacteriostatic water, alcohol swabs, insulin syringes.

2

Equilibrate Temperature

Remove the vial from storage and allow it to reach room temperature (5-10 minutes).

3

Sanitize

Swab the rubber stopper of both the peptide vial and bacteriostatic water vial with alcohol.

4

Draw Water

Draw 2.5 mL of bacteriostatic water into a syringe.

5

Add Water to Vial

Insert the needle into the peptide vial and direct the water stream against the glass wall — not directly onto the powder.

6

Mix Gently

Swirl the vial gently until the powder is fully dissolved. Never shake. The solution should be clear and colorless.

7

Store Properly

Refrigerate at 2-8°C. 24 months unopened, 30 days reconstituted.

Storage Temperature

2-8°C

Shelf Life

24 months unopened, 30 days reconstituted

Important Notes

  • Available primarily as oral capsules in research settings
  • Some research formulations may require reconstitution
  • Store away from light and moisture
  • Reconstituted solutions should be used within recommended timeframes

Safety & Side Effects

Reported Side Effects

  • !Increased appetite and food cravings
  • !Mild nausea or gastrointestinal discomfort
  • !Fatigue or drowsiness
  • !Headache
  • !Dizziness
  • !Water retention and mild edema
  • !Hyperglycemia or glucose intolerance
  • !Sleep disturbances
  • !Joint stiffness or arthralgia
  • !Potential mood changes or irritability

Potential Interactions

  • Diabetes medications - may affect glucose control
  • Growth hormone therapies - additive effects possible
  • Insulin - may influence glucose metabolism
  • Corticosteroids - may alter growth hormone responses
  • Appetite suppressants - opposing mechanisms of action

Important: Side effects and interactions listed here are compiled from published research and community reports. This is not a complete list. No formal drug interaction studies have been conducted for most research peptides. Always consult a qualified healthcare provider.

Research Studies

The following studies are referenced in this profile. PubMed IDs are provided where available for independent verification.

Anamorelin HCl (ONO-7643), a novel ghrelin receptor agonist, for the treatment of cancer anorexia-cachexia syndrome

Temel JS, Abernethy AP, Currow DC2016Journal of Clinical Oncology
PMID: 26834065

Phase III randomized controlled trial demonstrating anamorelin's efficacy in increasing body weight and improving appetite in cancer patients with cachexia.

Safety and efficacy of anamorelin in Japanese patients with cancer anorexia-cachexia syndrome

Katakami N, Uchitomi Y, Yamamoto N2018Supportive Care in Cancer

Japanese phase II/III study showing significant improvements in appetite, food intake, and quality of life measures with anamorelin treatment.

Ghrelin receptor agonist anamorelin improves body composition and clinical outcomes in non-small cell lung cancer patients

Currow D, Temel JS, Abernethy A2017Annals of Oncology

Multi-center trial demonstrating anamorelin's effects on lean body mass preservation and functional capacity in lung cancer patients.

Pharmacokinetics and pharmacodynamics of anamorelin in healthy volunteers and patients with advanced cancer

2015Clinical Pharmacology & Therapeutics

Comprehensive analysis of anamorelin's absorption, distribution, metabolism, and growth hormone stimulating effects across different populations.

Note: This is not an exhaustive list of all published research. Studies are selected for relevance and quality. Click PubMed IDs to verify sources independently. Inclusion does not imply endorsement of the peptide for any clinical use.

Frequently Asked Questions

Most research subjects experience increased appetite within 24-72 hours of starting anamorelin. Peak appetite stimulation typically occurs after 7-14 days of consistent administration.

Anamorelin can be taken with or without food, though some studies suggest taking it 30-60 minutes before meals may optimize appetite stimulation effects.

Anamorelin is a synthetic ghrelin receptor agonist with longer half-life and higher bioavailability than natural ghrelin. It provides more consistent and sustained activation of ghrelin receptors.

Research indicates anamorelin can promote weight gain through increased food intake and muscle preservation, though effects may vary based on baseline metabolic status and energy expenditure.

Anamorelin may cause mild increases in blood glucose through growth hormone stimulation. Research subjects with diabetes or glucose intolerance require careful monitoring.

Clinical trials have studied anamorelin for up to 12 weeks with generally acceptable safety profiles. Long-term effects beyond this timeframe require further investigation.

Anamorelin may have opposing effects when combined with appetite suppressants. Research protocols typically avoid concurrent use of medications affecting appetite or growth hormone pathways.

Many research protocols use evening dosing to align with natural growth hormone patterns, though morning administration has also been studied with positive results.

⚠️

Research & Educational Use Only

All content is for informational and research purposes only. This site does not provide medical advice, diagnosis, or treatment. Consult a qualified healthcare professional before using any peptide or supplement.

The information presented here is compiled from published research studies and is intended for informational purposes only. Individual results may vary. Always consult with a licensed healthcare provider.