How much does Novolog (insulin aspart protamine/insulin aspart) decrease blood sugar levels?

Novolog 70/30 Blood Sugar Reduction Effect

Novolog 70/30 (insulin aspart protamine/insulin aspart) decreases blood sugar levels by approximately 0.8-1.2 mmol/L (14-22 mg/dL) within 1-3 hours after injection, with a duration of action of 3-5 hours for the rapid-acting component and up to 24 hours for the intermediate-acting component. 1

Pharmacodynamic Properties

• Insulin aspart, the active ingredient in Novolog 70/30, works by stimulating peripheral glucose uptake by skeletal muscle and fat while inhibiting hepatic glucose production 1
• The maximum glucose-lowering effect of the rapid-acting component (insulin aspart) occurs between 1-3 hours after subcutaneous injection 1
• The duration of action for insulin aspart is 3-5 hours for the rapid component, while the protamine-bound portion provides intermediate-acting coverage for up to 24 hours 1
• The time course of action may vary considerably between different individuals or within the same individual based on various factors including injection site, exercise, and other variables 1

Clinical Effectiveness

• In clinical trials, insulin aspart has demonstrated better postprandial glycemic control compared to regular human insulin, with postprandial glucose levels 0.6-1.2 mmol/L lower after meals 2
• When used in a basal-bolus regimen, insulin aspart provided significantly greater improvements in glycosylated hemoglobin compared to regular human insulin 3
• The premixed formulation (70/30) combines both immediate and extended glucose-lowering effects in a single injection 1
• Studies show that insulin aspart has a faster onset and shorter duration of action than regular human insulin, allowing for more effective mealtime coverage 3, 4

Safety Considerations

• Hypoglycemia is the most commonly observed adverse reaction with insulin aspart, as with all insulin products 1
• The risk of severe hypoglycemia with premixed insulin formulations can be significant, with one study showing an unacceptable rate of hypoglycemia (64% of patients) with premixed 70/30 formulations compared to 24% with basal-bolus regimens 5
• A clinical trial comparing premixed insulin 70/30 to basal-bolus regimens was stopped after interim analysis due to the unacceptable rate of hypoglycemia in the premixed group 5
• Newer insulin formulations like glargine U300 have shown significantly lower rates of clinically significant hypoglycemia (<54 mg/dL) compared to older formulations 5

Practical Considerations

• The effect of Novolog 70/30 on blood glucose can be influenced by:
  • Injection site (absorption is faster from abdominal sites) 1
  • Physical activity (increases absorption rate) 1
  • Body temperature and blood flow 1
  • Individual patient factors such as insulin sensitivity 1
• For hospitalized patients, a target glucose range of 140-180 mg/dL is generally recommended when using insulin therapy 6
• The premixed formulation provides convenience but less flexibility compared to separate basal and bolus insulin administration 5

Common Pitfalls and Caveats

• Premixed insulin formulations like Novolog 70/30 have fixed ratios that cannot be adjusted to accommodate varying insulin needs throughout the day 5
• Studies have shown that basal-bolus insulin regimens provide better glycemic control with less risk of hypoglycemia compared to premixed formulations 5
• Patients using Novolog 70/30 must maintain consistent meal timing and carbohydrate content to avoid hypoglycemia 1
• Concomitant use with PPAR-gamma agonists (thiazolidinediones) can cause dose-related fluid retention and potentially exacerbate heart failure 1
• Insulin requirements may change with illness, emotional disturbances, stress, or changes in exercise patterns 1