How should I increase the dose of NovoLog Mix 70/30 (insulin aspart protamine/insulin aspart) for a patient taking 30 units in the morning and 30 units in the evening who has consistently high pre‑meal or fasting glucose (>180 mg/dL) despite diet and activity adherence?

Increasing NovoLog Mix 70/30 for Persistent Hyperglycemia

For a patient on NovoLog Mix 70/30 (30 units twice daily) with consistently high glucose (>180 mg/dL), you should immediately discontinue the premixed insulin and transition to a scheduled basal-bolus regimen, as premixed formulations are explicitly contraindicated for dose titration and carry unacceptable hypoglycemia risk.

Critical Problem with Current Regimen

• NovoLog Mix 70/30 is explicitly contraindicated in hospitalized patients because randomized trials showed a 64% hypoglycemia rate versus 24% with basal-bolus therapy, leading to early trial termination. 1
• The fixed 70:30 ratio cannot be adjusted independently, preventing you from addressing fasting versus post-prandial hyperglycemia separately and increasing hypoglycemia risk when meal intake varies. 2
• Major diabetes guideline societies do not recommend premixed 70/30 insulin for initial therapy or dose titration due to safety concerns. 2
• Premixed insulin requires consistent meal timing and carbohydrate intake, making it unsuitable for patients with variable eating patterns. 1

Immediate Transition to Basal-Bolus Therapy

Calculate Total Daily Dose (TDD)

• Current TDD = 60 units (30 units BID)
• For severe hyperglycemia (glucose >180 mg/dL), you need 0.3–0.5 units/kg/day as your target TDD. 2

Split Into Basal and Prandial Components

• Basal insulin (glargine or detemir): Give 50% of TDD = 30 units once daily at bedtime. 2, 3
• Prandial insulin (lispro or aspart): Give 50% of TDD = 30 units total, divided as 10 units before each of the three main meals. 2, 3
• Administer rapid-acting insulin 0–15 minutes before meals for optimal post-prandial control. 2

Systematic Titration Algorithm

Basal Insulin Titration

• If fasting glucose 140–179 mg/dL: Increase basal dose by 2 units every 3 days. 2
• If fasting glucose ≥180 mg/dL: Increase basal dose by 4 units every 3 days. 2
• Target fasting glucose: 80–130 mg/dL. 2
• Stop basal escalation when dose reaches 0.5–1.0 units/kg/day without achieving targets; add more prandial insulin instead. 2

Prandial Insulin Titration

• Increase each meal dose by 1–2 units (≈10–15%) every 3 days based on 2-hour post-prandial glucose. 2, 3
• Target post-prandial glucose: <180 mg/dL. 2, 3
• If hypoglycemia occurs (<70 mg/dL), reduce the implicated dose by 10–20% immediately. 2

Correction Insulin Protocol

• Add 2 units rapid-acting insulin for pre-meal glucose >250 mg/dL. 2
• Add 4 units for pre-meal glucose >350 mg/dL. 2
• Correction doses are in addition to scheduled prandial doses, never a replacement. 2

Monitoring Requirements

• Daily fasting glucose to guide basal insulin adjustments. 2
• Pre-meal glucose before each meal to calculate correction doses. 2
• 2-hour post-prandial glucose after each meal to assess prandial adequacy. 2, 3
• Bedtime glucose to evaluate overall daily pattern. 2
• Reassess insulin doses every 3 days during active titration. 2

Foundation Therapy with Metformin

• Continue metformin at maximum tolerated dose (up to 2,000–2,550 mg daily) when transitioning to basal-bolus insulin. 2
• Metformin reduces total insulin requirements by 20–30% and provides superior glycemic control compared with insulin alone. 2
• Never discontinue metformin when starting or intensifying insulin unless contraindicated. 2

Expected Clinical Outcomes

• With properly implemented basal-bolus therapy, ≈68% of patients achieve mean glucose <140 mg/dL, compared with ≈38% using inadequate regimens like premixed insulin. 2
• HbA1c reduction of 2–3% is achievable within 3–6 months with intensive titration. 2
• Basal-bolus therapy does not increase hypoglycemia incidence when correctly applied versus premixed formulations. 2

Critical Pitfalls to Avoid

• Never continue premixed insulin when dose titration is needed; the fixed ratio prevents independent adjustment of basal versus prandial coverage. 1, 2
• Do not attempt to "increase" NovoLog Mix 70/30 by simply raising the total dose; this simultaneously increases both components in a fixed ratio, leading to either persistent hyperglycemia or hypoglycemia. 1, 2
• Avoid relying on correction (sliding-scale) insulin alone without scheduled basal and prandial doses; this reactive approach is condemned by major diabetes guidelines. 2
• Do not delay transition to basal-bolus therapy when glucose consistently exceeds 180 mg/dL on premixed insulin; prolonged hyperglycemia increases complication risk. 2

Alternative: Stepwise Prandial Addition (If Basal-Only First)

If you prefer a more gradual approach starting with basal insulin alone:

• Start basal insulin (glargine) at 10 units once daily (or 0.1–0.2 units/kg). 2
• Titrate basal insulin by 2–4 units every 3 days until fasting glucose reaches 80–130 mg/dL. 2
• When basal insulin approaches 0.5 units/kg/day without achieving targets, add 4 units rapid-acting insulin before the largest meal. 2, 4
• Add prandial insulin to additional meals sequentially as needed when post-meal glucose remains >180 mg/dL. 4

However, given your patient's persistent hyperglycemia (>180 mg/dL), immediate basal-bolus therapy is preferred over stepwise addition to achieve rapid control. 2, 3