Retatrutide (20 mg Vial) Dosage Protocol

Reconstitution and weekly titration guide for the 20 mg Retatrutide vial — the higher-capacity format of the GLP-1/GIP/glucagon triple agonist studied for weight management and metabolic health. Prepared at 10 mg/mL, the larger vial covers a full multi-week titration while keeping each injection volume small.

Quickstart Highlights

Retatrutide is a triple-receptor agonist that activates the GLP-1, GIP, and glucagon receptors at the same time — a combination researched for appetite regulation, insulin response, and energy expenditure. Its extended half-life of roughly six days supports a once-weekly cadence. The 20 mg vial is the high-capacity option: reconstituted at 10 mg/mL it delivers an entire titration from a single vial while holding each injection to a low volume.

  • Reconstitute: Add 2.0 mL bacteriostatic water → 10 mg/mL concentration
  • Weekly titration: 2 mg → 4 mg → 8 mg → 12 mg across 13+ weeks
  • Easy measuring: At 10 mg/mL, 1 unit on a U-100 syringe = 100 mcg (so 2 mg = 20 units)
  • Storage: Lyophilized: −20 °C (−4 °F) or colder; Reconstituted: 2–8 °C (35.6–46.4 °F), use within 2–4 weeks

Dosing & Reconstitution Guide

Weekly subcutaneous titration using the concentrated 20 mg preparation

Weekly Subcutaneous Protocol (20 mg vial, 2 mL = 10 mg/mL)

Weeks Weekly Dose Syringe Volume (U-100) mL Equivalent
1–42,000 mcg (2 mg)20 units0.20 mL
5–84,000 mcg (4 mg)40 units0.40 mL
9–128,000 mcg (8 mg)80 units0.80 mL
13+12,000 mcg (12 mg)120 units1.20 mL*

Administration: Once weekly via subcutaneous injection. *When the 12 mg maintenance dose exceeds 1.0 mL, split it across two injection sites or draw from a second reconstituted vial. At 10 mg/mL the 20 mg vial delivers the full titration in roughly half the injection volume of a 5 mg/mL preparation.

Reconstitution Steps

  1. Draw 2.0 mL bacteriostatic water using a sterile syringe
  2. Inject slowly down the vial wall to avoid foaming
  3. Gently swirl/roll until fully dissolved (do not shake vigorously)
  4. Label with reconstitution date
  5. Refrigerate at 2–8 °C (35.6–46.4 °F), protected from light
  6. Use within 2–4 weeks

Result: 10 mg/mL concentration

Storage Guidelines

Key Administration Notes

⚠️ Research & Educational Purposes Only

This information is provided for research and educational purposes only. Peptides discussed are intended for laboratory research use only and are not approved for human consumption. Always consult qualified healthcare professionals for medical advice. Individual results may vary. This is not medical advice.