What is the concentration of insulin in the premixed bag (units per mL)?

• A. 0.5
• B. 1
• C. 2
• D. 10

Answer: (B)

Concentration is found by dividing the total insulin units by the total milliliters in the bag. If a premixed insulin bag has an equal amount of units and volume (for example, 100 units in 100 mL), the concentration becomes 1 unit per mL. This 1 unit/mL setup is a common standard for IV insulin infusions in clinical practice, which is why it’s the best fit for a premixed bag scenario. The other values would require different unit-to-mL ratios (0.5, 2, or 10 units per mL imply different combinations of total units and total volume). Therefore, 1 unit per mL is the correct concentration.