What is the initial morning and evening dose of 70/30 (pre-mixed) insulin for a patient?

Initial Dosing of 70/30 Premixed Insulin

The initial dose of 70/30 premixed insulin should be 0.1-0.2 units/kg per day or 10 units once or twice daily, typically administered before breakfast and before dinner.

Understanding 70/30 Premixed Insulin

70/30 premixed insulin contains:

• 70% intermediate-acting insulin (NPH)
• 30% short-acting insulin (regular)

This combination provides both:

• Immediate glucose control (from the regular insulin component)
• Extended coverage (from the NPH component)

Dosing Protocol

Initial Dosing:

• Starting dose: 0.1-0.2 units/kg/day 1 or 10 units 2
• Administration schedule: Typically divided into two daily injections
  • Morning dose: Before breakfast
  • Evening dose: Before dinner

Dose Distribution:

For twice-daily regimen:

• Morning dose: 2/3 of total daily dose
• Evening dose: 1/3 of total daily dose 1

For example:

• If total daily dose is 30 units
• Morning dose: 20 units (2/3)
• Evening dose: 10 units (1/3)

Titration and Adjustment

After initiating therapy, adjust doses based on blood glucose monitoring:

• Fasting glucose target: 90-150 mg/dL (5.0-8.3 mmol/L) 1
• Adjustment rule: If 50% of fasting glucose values are above target, increase dose by 2 units 1
• Hypoglycemia precaution: If >2 glucose readings/week are <80 mg/dL, decrease dose by 2 units 1

Special Considerations

Elderly Patients

• Consider starting at the lower end of the dosing range
• May need to simplify regimen if cognitive or functional decline occurs 1
• For older adults, consider using 70% of total calculated dose 1

Overweight/Obese Patients

• May require higher insulin doses
• Consider weight-based dosing rather than fixed starting dose

Important Cautions

1. Hypoglycemia risk: Monitor closely, especially during initiation phase
2. Injection timing: Administer consistently in relation to meals
3. Rotation of injection sites: Rotate within the same anatomical region
4. Storage: Keep unopened insulin refrigerated; in-use insulin can be kept at room temperature for up to 28 days

Common Pitfalls to Avoid

1. Using a single daily dose: 70/30 insulin is designed for twice-daily administration in most cases
2. Inconsistent meal timing: Premixed insulin requires consistent meal timing to avoid hypoglycemia
3. Inadequate monitoring: Frequent blood glucose monitoring is essential during initiation
4. Failure to adjust: Insulin doses should be titrated based on glucose patterns

Remember that while these are general guidelines, the insulin dose should be adjusted based on the individual's response to therapy, with the primary goal of avoiding hypoglycemia while achieving reasonable glycemic control.