Retatrutide (GLP-3R) 10mg Dosage Protocol

Quickstart Highlights

Retatrutide is an investigational triple-receptor agonist peptide targeting GLP-1, GIP, and glucagon receptors, under development for obesity and type 2 diabetes.

  • Phase 2 trials have shown remarkable weight-loss efficacy, with participants losing up to 24% of body weight at 48 weeks on higher doses.
  • This protocol provides an educational framework for once-weekly subcutaneous administration with gradual titration to reduce gastrointestinal side effects.

Preparation & Storage:

  • Reconstitute with 1.0 mL bacteriostatic water → ~10 mg/mL
  • Dose range: 2–8 mg weekly (gradual escalation over 8–12 weeks)
  • Measurement: 1 unit (U-100 syringe) = 0.01 mL ≈ 100 mcg
  • Lyophilized: Freeze at −20 °C (−4 °F)
  • Reconstituted: Refrigerate at 2–8 °C (35.6–46.4 °F) for up to 4 weeks

Dosing & Reconstitution Guide

Educational guide for reconstitution and daily dosing

Standard / Gradual Approach (1 mL ≈ 10 mg/mL)

Phase Weekly Dose Units (per injection) (mL) Vials Needed
Weeks 1–4 2 mg (2000 mcg) 20 units (0.20 mL) 1 vial per dose
Weeks 5–8 4 mg (4000 mcg) 40 units (0.40 mL) 1 vial per dose
Weeks 9–12 6 mg (6000 mcg) 60 units (0.60 mL) 1 vial per dose
Weeks 13+ 8 mg (8000 mcg) 80 units (0.80 mL) 1 vial per dose

Frequency:

  • All doses ≤10 mg can be drawn from one reconstituted 10 mg vial
  • Volumes >1.0 mL should be split into 2 injections at separate sites for optimal absorption

Reconstitution Steps

  • Draw 1.0 mL bacteriostatic water using a sterile syringe
  • Inject slowly along the vial wall; avoid foaming
  • Gently swirl or roll until fully dissolved (do not shake)
  • Label with preparation date
  • Refrigerate at 2–8 °C, protected from light
  • Use within 4 weeks

Important: This guide is for educational purposes only and is not medical advice. For research use only. Not for human consumption.

Advanced / Aggressive Protocol (1 mL ≈ 10 mg/mL)

Phase Weekly Dose Units (per injection) (mL) Vials Needed
Weeks 1–4 2 mg (2000 mcg) 20 units (0.20 mL) 1 vial per dose
Weeks 5–8 4 mg (4000 mcg) 40 units (0.40 mL) 1 vial per dose
Weeks 9–12 8 mg (8000 mcg) 80 units (0.80 mL) 1 vial per dose
Weeks 13+ 12 mg (12000 mcg) 120 units (1.20 mL) 2 vials per dose**

*The 12 mg dose (highest tested in Phase 2) requires combining 2 vials, drawing 1.2 mL total, and splitting into 2 subcutaneous injections. Gradual titration is critical to reduce gastrointestinal side effects.

Note: This protocol is for educational purposes only. Retatrutide is not FDA-approved and should only be used in research settings following trial protocols.

Supplies Needed

  • Retatrutide vials (10 mg each)
    • 12-week standard (up to 6 mg): 5 vials
    • 24-week standard (up to 8 mg): 15 vials
    • 12-week aggressive (up to 8 mg): 6 vials
  • U-100 Insulin Syringes (1 mL)
    • 1–2 syringes per week depending on dose
    • 12-week: 12–24 syringes
    • 24-week: 24–48 syringes
  • Bacteriostatic Water (10 mL bottles)
    • 1 mL per vial for reconstitution
    • 12-week: 5 mL → 1 bottle
    • 24-week: 15 mL → 2 bottles
  • Alcohol Swabs
    • 1 per vial + 1–2 per injection site
    • 12-week: ~50 swabs → 1 × 100-count box
    • 24-week: ~100 swabs → 1 × 100-count box

Protocol Overview

  • Goal: Achieve substantial weight loss and metabolic improvements through triple-receptor activation
  • Schedule: Weekly subcutaneous injections for 12–48 weeks
  • Dose Range: 2–12 mg weekly with 4-week titration steps
  • Reconstitution: 1 mL per 10 mg vial (~10 mg/mL)
  • Storage: Frozen lyophilized at −20 °C; reconstituted refrigerated for 4 weeks

Dosing Protocol

  • Start: 2 mg weekly for 4 weeks
  • Escalation: Increase by 2–4 mg every 4 weeks as tolerated
  • Target Dose:
    • Standard: 6–8 mg weekly
    • Advanced: 12 mg weekly
  • Frequency: Same day each week
  • Cycle Length: Minimum 24 weeks; trials extended to 48 weeks
  • Timing: Consistent day/time; rotate injection sites

Storage Instructions

Proper storage is essential to maintain peptide stability and integrity.

  • Lyophilized (Unmixed): Store in a freezer at approximately −20°C (−4°F) for long-term preservation. If freezing is not available, refrigeration (2–8°C) is acceptable for shorter durations. Keep in a dry, dark environment away from moisture.
  • After Reconstitution: Store the solution in a refrigerator at 2–8°C (35.6–46.4°F) at all times. Do not freeze once mixed.
  • Shelf Life: Use within 28 days after reconstitution for optimal stability and reliability. Discard any remaining solution after this period.

Important Notes

Key considerations for consistency, handling, and research accuracy.

  • Always use a new, sterile insulin syringe for each administration; do not reuse needles
  • Follow proper aseptic technique: clean both the vial stopper and injection site with separate alcohol swabs and allow to dry fully
  • Rotate injection sites (abdomen, thighs, upper arms) to reduce irritation and avoid tissue buildup
  • Administer injections slowly and steadily, allowing a few seconds before withdrawing the needle
  • Keep a record of dosing, timing, and injection sites to maintain consistency throughout the protocol
  • Do not use the solution if it appears cloudy, discolored, or contains visible particles
  • Store and handle peptides according to recommended conditions to preserve stability

How This Works

Retatrutide activates GLP-1, GIP, and glucagon receptors:

  • GLP-1 & GIP: Enhance glucose-dependent insulin secretion, suppress appetite
  • Glucagon: Increases metabolic rate, promotes energy expenditure, and enhances fat burning
  • Extended Half-Life (~6 days): Supports once-weekly dosing
  • Overall Effect: Reduced calorie intake, increased satiety, enhanced lipid oxidation, and improved glycemic control

Potential Benefits & Considerations

Benefits

  • Weight Loss: 22–24% body weight reduction at 48 weeks (8–12 mg doses)
  • Glycemic Control: HbA1c reduction of 1.3–2.0% in T2DM patients; ~82% reached HbA1c ≤6.5%
  • Cardiometabolic: Lower BP, LDL cholesterol, waist circumference, liver fat; >80% hepatic steatosis resolution
  • Universal Response: 100% achieved ≥5% weight loss on high doses

Side Effects

  • Mild-to-moderate GI symptoms: nausea, vomiting, diarrhea during dose escalation
  • Dose-dependent and transient
  • No severe hypoglycemia or serious treatment-related adverse events
  • Safety profile comparable to GLP-1 agonists when properly titrated

Lifestyle Factors

  • Follow a balanced diet to support metabolic and endocrine pathways
  • Maintain proper hydration for optimal physiological function
  • Prioritize sleep and recovery to support hormonal balance
  • Engage in regular physical activity to complement metabolic research models
  • Manage stress levels, as stress can impact hormone signaling
  • Avoid excessive processed foods when focusing on metabolic studies

Injection Technique

General guidance for subcutaneous administration:

  • Clean the vial stopper and injection area with alcohol and allow to dry
  • Gently pinch the skin and insert the needle at a 45–90° angle
  •  Inject slowly and steadily without aspirating
  • Hold the needle in place for a few seconds before removing
  • Rotate injection sites (abdomen, thighs, upper arms) to reduce irritation

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GLP-3R (10mg-20mg)

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  • High-purity, lab-tested peptide batches with quality verification.
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Important Note

This content is intended for educational and research purposes only and does not constitute medical advice, diagnosis, or treatment. GLP-3R (10mg-20mg) remains an investigational peptide with limited human clinical data. For research use only. Not for human consumption.

References

The Lancet (2023)
— Rosenstock J, et al. Retatrutide for type 2 diabetes: Phase 2 trial results (36-week study, HbA1c reductions, weight loss)

New England Journal of Medicine (2023)
— Jastreboff AM, et al. Triple-hormone-receptor agonist Retatrutide for obesity: Phase 2 trial (48-week study, up to 24% weight loss)

American Diabetes Association (2023)
— ADA Press Release: Novel agent Retatrutide results in substantial weight reduction (83rd Scientific Sessions, Phase 2 data)

ADA Meeting News (2023)
— Phase 2 trial results: benefits of Retatrutide in obesity, type 2 diabetes, NASH (83rd ADA Scientific Sessions coverage)

ClinicalTrials.gov
— Study of Retatrutide (LY3437943) in adults with obesity (NCT04881760; protocol details, dosing regimens)

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