NovoLog 70/30 Classification
NovoLog 70/30 is a premixed insulin formulation that contains both rapid-acting and intermediate-acting insulin components, not purely intermediate-acting insulin. Specifically, it consists of 30% rapid-acting insulin aspart and 70% intermediate-acting protamine-crystallized insulin aspart 1, 2.
Insulin Components and Pharmacokinetics
The formulation combines two distinct insulin types in a single product:
- 30% rapid-acting insulin aspart provides immediate prandial (mealtime) coverage with onset within 5 minutes and peak action at 1-2 hours 3
- 70% protamine-bound insulin aspart functions as the intermediate-acting component, providing extended basal coverage similar to NPH insulin 1, 4
This dual-action profile means NovoLog 70/30 addresses both prandial and basal insulin needs simultaneously 2, 5.
Clinical Classification
NovoLog 70/30 is classified as a premixed insulin analogue, not as a purely intermediate-acting insulin 3, 1. The intermediate-acting component (the protaminated portion) provides an extended duration of action comparable to NPH insulin, but the formulation as a whole cannot be categorized solely as intermediate-acting due to its rapid-acting component 1.
Key Distinguishing Features:
- Premixed insulins like NovoLog 70/30 differ fundamentally from pure intermediate-acting insulins (such as NPH or Lente insulin) which have onset at 1 hour, peak at 6-8 hours, and duration of 12 hours 3
- The rapid-acting component creates a biphasic action profile with both immediate and prolonged effects 5
- This combination allows for coverage of both postprandial glucose excursions and basal insulin requirements with fewer daily injections 2, 5
Clinical Implications
The premixed nature of NovoLog 70/30 has important practical considerations:
- Typically administered twice daily before breakfast and dinner 3, 5
- Provides superior postprandial glucose control compared to pure intermediate-acting insulins like NPH 2, 5
- Offers less flexibility than separate basal-bolus regimens but greater convenience for patients preferring fewer injections 3, 1
- The pharmacodynamic profile makes it suboptimal for precise postprandial control compared to separate basal-bolus regimens 1
Common pitfall: Clinicians sometimes mistakenly classify premixed insulins based solely on their predominant component (70% in this case), but the presence of any rapid-acting component fundamentally changes the classification from purely intermediate-acting to premixed 1.
Human regular insulin and NPH combinations (such as 70/30 NPH/regular) represent less costly alternatives to analog premixed insulins, though their pharmacodynamic profiles may be suboptimal 3.