Radiopharmaceutical Volume to Draw for a Prescribed Activity (10 CFR 35.63)
The volume to draw from a vial for a prescribed radiopharmaceutical activity.
Open the tool → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- Radionuclide
- Tc-99m (6.02 hours)
- Activity unit
- mCi
- Vial activity at calibration
- 100
- Vial volume
- 5 mL
- Vial calibration date and time
- 2026-10-12T07:00
- Prescribed activity at administration
- 25
- Draw date and time
- 2026-10-12T09:00
- Administration date and time, if later than the draw
- 2026-10-12T10:00
Result: Draw 1.766 mL; the syringe should read 28.05 mCi at draw time.
The tool opens with these values already filled in. Replace them with your own.
What you enter
- Radionuclide
- Half-life, for another radionuclide
- Half-life unit
- Activity unit
- Vial activity at calibration
- Vial volume
- Vial calibration date and time (YYYY-MM-DDTHH:MM)
- Prescribed activity at administration
The other 5 fields
- Draw date and time (YYYY-MM-DDTHH:MM)
- Administration date and time, if later than the draw
- Measured activity at draw time (optional)
- Prescribed range, lower end (optional)
- Prescribed range, upper end (optional)
How this is calculated
Citation
10 CFR 35.63(b), (c) and (d): dosage determination by decay correction or volumetric calculation, and the limits of the prescribed range and 20 percent of the prescribed dosage. Half-lives from the FDA labels cited by the decay tool. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.