How many NovoLOG (insulin aspart) FlexPen 100 UNIT/ML Solution Pen-injectors should be sent for a patient taking 1-12 units subcutaneously 3 times a day?

NovoLOG FlexPen Supply Calculation

For a patient taking 1-12 units of NovoLOG three times daily before meals, dispense 2-3 FlexPens per month, with 3 pens being the safer choice to ensure adequate supply.

Calculation Rationale

Daily and Monthly Insulin Requirements

• Maximum daily dose: 12 units × 3 times = 36 units per day 1
• Minimum daily dose: 1 unit × 3 times = 3 units per day 1
• Maximum monthly requirement (30 days): 36 units × 30 = 1,080 units 1
• Minimum monthly requirement: 3 units × 30 = 90 units 1

FlexPen Capacity and Supply

• Each NovoLOG FlexPen contains 300 units of U-100 insulin (3 mL) 1
• Standard FlexPens deliver doses in 1-unit increments up to a maximum of 60-80 units per injection 1
• The prescribed dose range (1-12 units) is well within the safe single-dose capacity of standard insulin pens 1

Number of Pens Required

• At maximum dosing: 1,080 units ÷ 300 units per pen = 3.6 pens per month 1
• At minimum dosing: 90 units ÷ 300 units per pen = 0.3 pens per month 1

Dispense 3 FlexPens for a 30-day supply to account for the maximum prescribed dose and provide a safety margin. 1

Clinical Considerations

Dosing Accuracy and Device Selection

• Insulin pens demonstrate superior accuracy compared to syringes, particularly at low doses (1-5 units), with pen-injectors showing 8-11% error versus 23% error with syringes at 1-unit doses 2, 3
• FlexPen devices consistently meet ISO accuracy standards across all dose ranges, with no clinically relevant deviations from prescribed doses 4
• The FlexPen is appropriate for this patient's dose range and may be preferred for patients with dexterity issues or vision impairment 5

Important Safety Considerations

• Never share insulin pens between patients due to risk of biological contamination 1
• Dispose of needles immediately after each use and never leave needles attached to pens between uses, as this can lead to air contamination and dose inaccuracy 1
• Prime the pen before each injection to ensure proper flow by observing at least one drop of insulin at the needle tip 1

Common Pitfalls to Avoid

• Underdispensing pens can lead to treatment interruption if the patient consistently uses higher doses within the prescribed range 1
• Patients should be educated that actual delivered doses may vary slightly when transferring between different insulin delivery devices 2
• Improper injection technique, such as releasing the thumb button before complete needle withdrawal, can result in incomplete dose delivery 1