How should I reconstitute 36 mg of Retatrutide to achieve a concentration of 12 mg/mL?

Reconstitution of Retatrutide to 12 mg/mL

To achieve a concentration of 12 mg/mL from 36 mg of Retatrutide, add 3 mL of bacteriostatic water for injection to the vial.

Calculation Method

• Using the basic formula: Final Volume (mL) = Total Drug Amount (mg) ÷ Desired Concentration (mg/mL), you need 36 mg ÷ 12 mg/mL = 3 mL of diluent 1

• This calculation follows the same mathematical principles used for reconstituting other injectable medications, such as vecuronium (10 mg reconstituted with 10 mL normal saline to achieve 1 mg/mL) 2

Step-by-Step Reconstitution Protocol

• Gather sterile supplies including the 36 mg Retatrutide vial, 3 mL bacteriostatic water for injection, alcohol swabs, and appropriate syringes under aseptic technique 1

• Inject 3 mL of bacteriostatic water slowly into the vial, directing the stream against the vial wall rather than directly onto the lyophilized powder to minimize foaming 1

• Gently swirl the vial (do not shake vigorously) until the powder is completely dissolved and the solution appears clear; this typically takes 1-2 minutes 1

• Inspect the reconstituted solution for particulate matter and discoloration before use; the solution should be clear and colorless 1

• Label the vial clearly with the final concentration (12 mg/mL), date and time of reconstitution, and your initials 1

Storage and Stability Considerations

• Refrigerate the reconstituted solution at 2-8°C (36-46°F) immediately after preparation; based on peptide stability data for similar GLP-1 receptor agonists, reconstituted Retatrutide should remain stable for up to 28 days when properly refrigerated 3, 4

• Protect from light by storing in the original carton or wrapping the vial in aluminum foil, as peptide medications are typically photosensitive 3, 4

• Allow to reach room temperature (15-20 minutes) before each injection to minimize injection site discomfort 3, 4

Dosing Verification

• At 12 mg/mL concentration, common Retatrutide doses translate to specific volumes: 4 mg = 0.33 mL, 8 mg = 0.67 mL, and 12 mg = 1.0 mL 3, 4

• Use an insulin syringe or tuberculin syringe for accurate measurement of small volumes, as dosing precision is critical for peptide medications 3, 4

Critical Safety Considerations

• Never use normal saline or sterile water without preservative for multi-dose vials, as bacteriostatic water contains 0.9% benzyl alcohol to prevent bacterial contamination over multiple uses 1

• Discard any unused solution after 28 days even if refrigerated, as peptide degradation and loss of sterility become concerns beyond this timeframe 3, 4

• Do not mix Retatrutide with other medications in the same syringe, as compatibility data is not available and co-administration may affect stability 3, 4