Is it safe to take 20 units of Novolog Mix 70/30 (insulin aspart protamine/insulin aspart) twice a day?

Novolog Mix 70/30 at 20 Units Twice Daily: Safety and Appropriateness

Yes, 20 units of Novolog Mix 70/30 twice daily can be safely administered, but this dose should be determined based on individual insulin requirements, body weight, and current glycemic control rather than as a universal starting point. 1

Initial Dosing Considerations

For patients initiating Novolog Mix 70/30 therapy, the American Diabetes Association recommends starting with 10 units per day OR 0.1-0.2 units/kg of body weight per day, divided into two equal doses 2, 1. This means:

• A 20-unit twice-daily regimen (40 units total daily) would be appropriate for patients weighing approximately 200-400 kg using the lower end of the dosing range 1
• For most adults, this 40-unit total daily dose represents a moderate to higher starting dose that may be more appropriate for patients already on insulin rather than insulin-naive patients 2

When 20 Units BID Is Appropriate

This dosing is reasonable for:

• Patients transitioning from other insulin regimens where the total daily dose can be divided into two equal doses of Novolog Mix 70/30 1
• Patients previously on 70/30 premixed insulin twice daily (e.g., 30 units morning and 20 units evening) who are being converted, where the usual morning dose becomes the evening dose and half the usual evening dose becomes the morning dose 2
• Patients who have titrated up from lower doses following the recommended increase of 2 units every 3 days to reach fasting glucose targets 1

Administration Protocol

Timing is critical for safety and efficacy:

• Administer 30 minutes before breakfast and 30 minutes before dinner 1
• Meals must be consumed at consistent times every day when on premixed insulin 2
• Do not skip meals to reduce hypoglycemia risk 2

Important Safety Caveats

Premixed insulin carries specific risks that require vigilance:

• Premixed human insulin 70/30 has been associated with unacceptably high rates of iatrogenic hypoglycemia in hospital settings and is not recommended for inpatient use 2
• The risk of hypoglycemia with twice-daily premixed insulin is 4-6 times higher than with sliding scale insulin alone 2
• For hypoglycemia management: if blood glucose drops, decrease the dose by 10-20% 2, 1

Patients on premixed insulin must:

• Eat similar amounts of carbohydrates each day to match the fixed insulin doses 2
• Carry a source of quick-acting carbohydrates (15-20g glucose) at all times 2
• Understand that physical activity may cause hypoglycemia depending on timing 2

Monitoring and Titration

Close follow-up is essential:

• Evaluate glycemic control every 2 weeks and adjust therapy as needed 1
• Set a fasting plasma glucose target and increase by 2 units every 3 days if 50% of readings are above target 1
• If A1C remains above goal with twice-daily dosing, consider advancing to three-times-daily premixed insulin or switching to basal-bolus regimen 1

Alternative Considerations

For better physiologic insulin coverage:

• Consider switching to basal insulin (glargine or detemir) plus rapid-acting insulin (lispro or aspart) for more flexible dosing 2
• This approach allows separate adjustment of basal and prandial components and may reduce hypoglycemia risk 2

The 20-unit twice-daily dose represents a moderate insulin requirement that can be safe and effective when properly monitored, but it should not be used as a universal starting dose for insulin-naive patients 2, 1.