What are the onset, peak, duration, dosing guidelines, administration timing, storage recommendations, and alternative rapid‑acting insulins for Novolog (insulin aspart) in diabetes?

Novolog (Insulin Aspart) Clinical Reference

Pharmacokinetic Profile

Novolog has an onset of action within 5 minutes, peaks at 1-2 hours, and has a duration of 3-4 hours. 1

• Onset: 5 minutes after subcutaneous injection 1
• Peak effect: 1-3 hours, with maximum glucose-lowering occurring during this window 2
• Duration: 3-5 hours of glucose-lowering activity 1, 2
• The median time to maximum insulin concentration is 40-50 minutes, approximately half that of regular human insulin (80-120 minutes) 2

Administration Timing

Inject Novolog subcutaneously within 5-10 minutes before a meal. 2

• This timing capitalizes on its rapid onset to match postprandial glucose excursions 2
• Novolog provides superior postprandial glucose control compared to regular human insulin given 30 minutes before meals 3
• The faster absorption profile—approximately twice as fast as regular insulin—allows for more physiologic mealtime coverage 3, 4

Dosing Guidelines

Novolog should be used as part of a basal-bolus regimen with intermediate- or long-acting insulin. 2

• Individualize dosing based on metabolic needs, blood glucose monitoring, and glycemic targets 2
• Adjust doses with changes in physical activity, meal patterns (macronutrient content or timing), renal/hepatic function, or acute illness 2
• The American Diabetes Association recommends rapid-acting insulin analogues like Novolog as the prandial component in basal-bolus regimens for both type 1 and type 2 diabetes 5

Administration Routes

Subcutaneous injection: 2

• Inject into the abdominal area, thigh, buttocks, or upper arm
• Rotate injection sites within the same region to reduce risk of lipodystrophy and localized cutaneous amyloidosis

Continuous subcutaneous infusion (insulin pump): 2

• Use only in pumps compatible with Novolog per manufacturer instructions
• Do not mix with other insulins or diluents in the pump
• Rotate infusion sites within recommended regions

Intravenous administration: 2

• Dilute to concentrations of 0.05-1 unit/mL in polypropylene infusion bags
• Stable in 0.9% Sodium Chloride Injection, USP

Storage Recommendations

Refrigerate unopened vials at 36-46°F (2-8°C); in-use insulin may be kept at room temperature. 1

• Avoid extreme temperatures (<36°F or >86°F, <2°C or >30°C) 1
• Avoid excess agitation to prevent loss of potency, clumping, frosting, or precipitation 1
• Insulin in use may be kept at room temperature to limit local irritation from cold insulin 1
• Always maintain a spare bottle of each insulin type used 1
• Check expiration dates; potency may decrease after opening even before the stamped date 1

Visual Inspection

Novolog should appear clear and colorless before each use. 1

• Inspect for changes including clumping, frosting, precipitation, or changes in clarity or color that signal loss of potency 1
• Discard if any abnormalities are observed 1

Alternative Rapid-Acting Insulins

Humalog (insulin lispro) is the primary alternative, with nearly identical pharmacokinetics to Novolog. 5

• Humalog (lispro): 5-minute onset, 1-2 hour peak, 3-4 hour duration 1
• Apidra (glulisine): Similar rapid-acting profile recommended by the American Diabetes Association 5
• Humalog and Novolog have essentially identical action profiles but are distinct pharmaceutical products requiring a new prescription to switch 5
• Rapid-acting analogues provide an additional ~0.15% HbA1c reduction and significantly lower hypoglycemia risk compared to regular human insulin 5

Clinical Advantages

Novolog reduces hypoglycemia risk compared to regular human insulin while improving glycemic control. 1, 5

• In type 1 diabetes, analog insulins are associated with less hypoglycemia, less weight gain, and lower A1C compared to human insulins 1
• The shorter duration of action (3-4 hours vs. 16+ hours for regular insulin) reduces dose overlap and hypoglycemia risk, particularly important for elderly patients, those with chronic kidney disease, or variable oral intake 6
• Nocturnal and severe hypoglycemic events occur less frequently with Novolog than regular human insulin 7, 8

Critical Safety Considerations

Never share Novolog pens, cartridges, or devices between patients, even if the needle is changed. 2

• Accidental mix-ups between insulin products can occur—instruct patients to check insulin labels before every injection 2
• Increase blood glucose monitoring frequency when making any changes to insulin regimen (strength, manufacturer, type, injection site, or administration method) 2
• Hypoglycemia may be life-threatening; increase monitoring with dosage changes, concomitant glucose-lowering medications, meal pattern changes, physical activity changes, or in patients with renal/hepatic impairment 2

Available Formulations

Novolog is available as 100 units/mL (U-100) in: 2

• 10 mL multiple-dose vials
• 3 mL PenFill® prefilled cartridges
• 3 mL FlexPen® prefilled pens