What is the recommended dosing regimen for 70/30 (Novolin, Humulin) insulin?

Dosing 70/30 Insulin

For patients requiring 70/30 insulin (Novolin, Humulin), the recommended starting dose is 0.1-0.2 units/kg/day divided into two daily injections, with approximately 60% of the total daily dose given before breakfast and 40% before dinner. 1

Initial Dosing and Administration

• Starting dose: 0.1-0.2 units/kg/day for insulin-naive patients
• Timing of injections:
  • Morning dose: 30 minutes before breakfast (for human 70/30) or 10-15 minutes before breakfast (for insulin analog 70/30)
  • Evening dose: 30 minutes before dinner (for human 70/30) or 10-15 minutes before dinner (for insulin analog 70/30)
• Distribution ratio: 60:40 (morning:evening) is generally more effective than a 50:50 split 2

Dose Titration

• Adjust doses based on self-monitoring of blood glucose (SMBG) patterns
• Increase morning dose by 2-4 units if pre-dinner glucose is consistently elevated
• Increase evening dose by 2-4 units if fasting morning glucose is consistently elevated
• Titrate every 3-7 days until target glucose values are achieved
• Target pre-meal glucose: 80-130 mg/dL

Special Considerations

When to Use 70/30 Insulin

70/30 insulin is most appropriate for:

• Patients who need both basal and prandial coverage but prefer fewer daily injections
• Patients with consistent daily routines and meal patterns
• Elderly patients who may have difficulty managing multiple insulin types

When to Avoid 70/30 Insulin

• Hospital setting: Premixed insulin therapy (70/30) has been associated with an unacceptably high rate of iatrogenic hypoglycemia and is generally not recommended for inpatient use 1
• Patients with erratic eating patterns or unpredictable schedules
• Patients requiring more precise insulin adjustment

Monitoring and Adjustments

• Monitor blood glucose before breakfast and dinner daily during initiation
• Check for patterns of hypoglycemia (glucose <70 mg/dL) or persistent hyperglycemia
• If target glucose levels are not achieved with twice-daily dosing, consider:
  1. Adding a third injection of 70/30 insulin before lunch (studies show improved HbA1c without increased hypoglycemia) 3
  2. Switching to a basal-bolus regimen for more flexible dosing

Common Pitfalls to Avoid

1. Fixed ratio limitation: The fixed 70/30 ratio cannot be adjusted to meet varying basal and prandial needs throughout the day
2. Hypoglycemia risk: The intermediate-acting component may peak during the night, increasing risk of nocturnal hypoglycemia
3. Meal timing: Patients must maintain consistent meal timing and carbohydrate content
4. Sliding scale misuse: Avoid using 70/30 insulin in a sliding scale manner; it's designed for scheduled dosing

Transitioning from Other Regimens

• From oral agents: Start with 10 units or 0.1-0.2 units/kg/day divided into two doses
• From basal insulin: Calculate total daily basal dose and increase by 10-20%, then divide using the 60:40 morning:evening ratio
• From basal-bolus: Add total daily insulin dose, reduce by 20%, and divide using the 60:40 ratio

Remember that while 70/30 insulin offers convenience with fewer injections, it provides less flexibility than basal-bolus regimens and requires consistent daily routines for optimal efficacy and safety.