A semaglutide 5 mg/mL compounded vial contains 5 milligrams of active drug per milliliter. To convert prescribed milligrams to milliliters, divide by 5. Standard titration steps are 0.05 mL for 0.25 mg, 0.1 mL for 0.5 mg, 0.2 mL for 1 mg, 0.34 mL for 1.7 mg, and 0.48 mL for 2.4 mg. Most pharmacies dispense U-100 insulin syringes, where 0.01 mL equals 1 unit.
What 5 mg/mL Means
“5 mg/mL” is a concentration. It tells you how much active semaglutide is in each milliliter of the solution. With a 5 mg/mL vial:
- 1 mL contains 5 mg of semaglutide
- 0.5 mL contains 2.5 mg
- 0.1 mL contains 0.5 mg
- 0.01 mL contains 0.05 mg
To calculate any dose: dose (mg) divided by 5 = volume (mL). For example, 1.7 mg divided by 5 = 0.34 mL.
Standard Wegovy Titration in 5 mg/mL Compound
| Week Range | Dose (mg/week) | Volume (mL) | Insulin Syringe Units (U-100) |
|---|---|---|---|
| 1 to 4 (starter) | 0.25 mg | 0.05 mL | 5 units |
| 5 to 8 | 0.5 mg | 0.10 mL | 10 units |
| 9 to 12 | 1.0 mg | 0.20 mL | 20 units |
| 13 to 16 | 1.7 mg | 0.34 mL | 34 units |
| 17 and on | 2.4 mg | 0.48 mL | 48 units |
Microdosing and Custom Steps
Some prescribers and patients use intermediate doses to manage side effects more gradually. The math:
| Custom Dose | Volume (mL) | U-100 Units |
|---|---|---|
| 0.125 mg (microdose) | 0.025 mL | 2.5 units |
| 0.375 mg | 0.075 mL | 7.5 units |
| 0.75 mg | 0.15 mL | 15 units |
| 1.25 mg | 0.25 mL | 25 units |
| 1.5 mg | 0.30 mL | 30 units |
| 2.0 mg | 0.40 mL | 40 units |
Why Pharmacies Use Different Concentrations
- 2 mg/mL: larger volumes per dose, easier for very low doses
- 2.5 mg/mL: intermediate; common in some compounded products
- 5 mg/mL: common standard, balances volume and precision
- 10 mg/mL: smallest volumes, allows long-duration vials but requires more precision
The same prescribed dose in mg gives different volumes depending on concentration. Always check the vial label.
How to Measure with a U-100 Insulin Syringe
- Wash hands and gather supplies (vial, syringe, alcohol wipe, sharps container)
- Wipe vial top with alcohol; let it dry
- Pull air into the syringe equal to your dose volume
- Insert into the vial; inject the air
- Invert the vial; pull semaglutide to your prescribed unit mark
- Tap to clear any air bubbles; push out and re-pull if needed
- Confirm volume against your printed dose chart
- Inject subcutaneously per your prescriber’s instructions
- Discard syringe in a sharps container
Storage of 5 mg/mL Compounded Semaglutide
- Refrigerate at 36 to 46 F
- Follow the pharmacy’s beyond-use date (typically 28 to 90 days after first puncture)
- Do not freeze
- Use a fresh syringe and needle for every dose
- Wipe vial top with alcohol before each access
- Check for cloudiness, particles, or color change before each dose
Common Measurement Errors to Avoid
- Confusing mL and units (10 units = 0.1 mL, not 1.0 mL)
- Pulling air into the dose by mistake
- Using a syringe meant for a different concentration
- Eyeballing volumes instead of using markings
- Reusing the same syringe (never)
- Confusing 0.025 mL (a microdose) with 0.25 mL (10x too much)
What If My Pharmacy Lists Different Volumes?
Always defer to your pharmacy’s printed instructions. Some compounded products contain stabilizers or buffers that slightly change the math, or the active concentration may differ from the labeled “5 mg/mL” by a small calibration. Pharmacies may also dispense vials with rounded dosing for ease of measurement (5, 10, 20, 30, 40 units instead of fractional values).
Compounded Semaglutide and the FDA’s Shortage Resolution
Compounded semaglutide is now narrowly restricted in the United States after the FDA declared the shortage resolved in 2025. Active prescriptions must meet specific exceptions (allergy to inactive ingredient, etc.). Some pharmacies have shifted away from compounded semaglutide to brand Wegovy. If you are starting a new compounded prescription, verify the pharmacy is operating under a legitimate exception. See our overview of treatment options for context.
Related Reading
For more on semaglutide dosing and compounded versus brand options, see our guides on treatment options and prediabetes basics.
The Bottom Line
A 5 mg/mL semaglutide compounded vial contains 5 mg per milliliter. Standard titration converts to 0.05 mL (5 units) for 0.25 mg, 0.1 mL (10 units) for 0.5 mg, 0.2 mL (20 units) for 1 mg, 0.34 mL (34 units) for 1.7 mg, and 0.48 mL (48 units) for 2.4 mg on a U-100 insulin syringe. Always cross-check against your pharmacy’s printed dose card and the actual vial label, since concentrations can vary slightly between batches and pharmacies. Refrigerate, follow the beyond-use date, and use a fresh syringe each dose.
