How do I calculate the volume of Lantus (insulin glargine) to administer when the prescribed dose is 44 units and the concentration is 100 units/ml?

Calculating Lantus Volume for Administration

For a 44-unit dose of Lantus at 100 units/mL concentration, you will administer 0.44 mL.

The Calculation

The formula for calculating insulin volume is straightforward:

Volume (mL) = Dose (units) ÷ Concentration (units/mL)

For your specific case:

• Dose ordered: 44 units
• Concentration: 100 units/mL
• Volume to administer: 44 ÷ 100 = 0.44 mL

Practical Administration Considerations

Syringe Selection

• Use a 0.5 mL or 1 mL insulin syringe marked in units for accurate dosing, as these allow doses up to 50 units and 100 units respectively 1
• Most insulin syringes are calibrated for U-100 insulin (100 units/mL), making them ideal for Lantus administration 1

Dosing Verification

• Insulin pens are preferred over syringes in most cases for patients on multiple daily injections, as they facilitate accurate dosing and administration 1
• If using a syringe, draw up to the 44-unit mark on a U-100 insulin syringe, which corresponds to 0.44 mL 1

Critical Safety Points

• Never dilute or mix Lantus with any other insulin or solution due to its low pH formulation 2
• Lantus must be administered as a separate injection when combining with other insulins 2
• Use proper injection technique with 4-5 mm needles to minimize risk of intramuscular injection and lipohypertrophy 1

Administration Timing

• Lantus should be administered once daily at the same time each day for optimal basal insulin coverage 2
• The typical starting dose for insulin-naive type 2 diabetes patients is 10 units or 0.1-0.2 units/kg/day, though your patient's 44-unit dose suggests they are already on established therapy 2