How should I adjust the regimen for a patient with hemoglobin A1c 9.9% who is on metformin extended‑release 750 mg daily, insulin glargine (Lantus) 25 U at bedtime, and sliding‑scale insulin aspart (NovoLog)?

Aggressive Insulin Intensification Required for Severe Uncontrolled Diabetes

This patient with A1c 9.9% on inadequate insulin therapy requires immediate basal insulin escalation to 40–50 units daily, addition of prandial insulin coverage (4–6 units before each meal), and optimization of metformin to 2000 mg daily. 1

Critical Problems with Current Regimen

• The current regimen—25 units Lantus, sliding-scale NovoLog, and only 750 mg metformin—is profoundly inadequate for an A1c of 9.9%, representing therapeutic failure that requires immediate intervention 1
• Sliding-scale insulin as the primary regimen is explicitly condemned by all major diabetes guidelines because only 38% of patients achieve mean glucose <140 mg/dL versus 68% with scheduled basal-bolus therapy 2
• The metformin dose of 750 mg daily is subtherapeutic; the maximum effective dose is 2000–2550 mg daily, and this medication must be optimized before further insulin intensification 1

Immediate Medication Adjustments

1. Optimize Metformin Foundation Therapy

• Increase metformin to 1000 mg twice daily (2000 mg total) immediately unless contraindicated by renal impairment (eGFR <30 mL/min/1.73m²) 1
• Metformin reduces total insulin requirements by 20–30% and provides superior glycemic control when combined with insulin compared to insulin alone 3, 4
• Continue metformin even when intensifying insulin therapy—never discontinue unless contraindicated 1

2. Aggressive Basal Insulin Escalation

• Increase Lantus from 25 units to 40–50 units once daily at bedtime (approximately 0.4–0.5 units/kg for a typical adult) 1
• For A1c 9.9%, guidelines recommend starting doses of 0.3–0.5 units/kg/day as total daily insulin, meaning this patient needs substantially more basal coverage 1, 2
• Titrate basal insulin by 4 units every 3 days until fasting glucose consistently reaches 80–130 mg/dL 1
• If fasting glucose is 140–179 mg/dL, increase by 2 units every 3 days; if ≥180 mg/dL, increase by 4 units every 3 days 1

3. Initiate Scheduled Prandial Insulin Coverage

• Discontinue sliding-scale NovoLog as monotherapy immediately and replace with scheduled basal-bolus regimen 2
• Start NovoLog 4–6 units before each of the three main meals (breakfast, lunch, dinner), administered 0–15 minutes before eating 1
• Alternatively, use 10% of the current basal dose (approximately 4 units) as the starting prandial dose 1, 2
• Titrate each meal dose by 1–2 units every 3 days based on 2-hour postprandial glucose readings, targeting <180 mg/dL 1

4. Correction Insulin Protocol (Adjunct Only)

• Add correction doses of NovoLog in addition to scheduled prandial insulin: 2 units for pre-meal glucose >250 mg/dL and 4 units for glucose >350 mg/dL 1, 2
• Correction insulin is intended only as a supplement to scheduled basal and prandial insulin, never as a replacement 2

Critical Threshold: Recognizing When to Stop Basal Escalation

• When basal insulin approaches 0.5–1.0 units/kg/day (approximately 50–100 units for most adults), stop further basal escalation and focus on intensifying prandial insulin instead 1
• Clinical signals of "overbasalization" include: basal dose >0.5 units/kg/day, bedtime-to-morning glucose differential ≥50 mg/dL, hypoglycemia episodes, and high glucose variability 1, 2
• Continuing to escalate basal insulin beyond this threshold leads to increased hypoglycemia risk without improved glycemic control 1

Monitoring Requirements

• Daily fasting blood glucose monitoring is essential during titration—patient should check fasting glucose every morning and adjust basal insulin accordingly 1
• Check pre-meal and 2-hour postprandial glucose to guide prandial insulin adjustments 1
• Reassess HbA1c every 3 months during intensive titration; expect HbA1c reduction of 2–3% from baseline over 3–6 months with proper basal-bolus therapy 1, 2

Expected Clinical Outcomes

• With appropriate basal-bolus therapy at weight-based dosing, 68% of patients achieve mean glucose <140 mg/dL versus only 38% with sliding-scale alone 2
• Anticipated HbA1c reduction of 2–3% (from 9.9% to approximately 7–8%) over 3–6 months with intensive insulin titration 1, 2
• Properly implemented basal-bolus regimens do not increase hypoglycemia incidence compared to inadequate sliding-scale approaches 2

Hypoglycemia Management

• Treat any glucose <70 mg/dL immediately with 15 grams of fast-acting carbohydrate, recheck in 15 minutes, and repeat if needed 1
• If hypoglycemia occurs without clear cause, reduce the implicated insulin dose by 10–20% immediately 1

Patient Education Essentials

• Proper insulin injection technique and site rotation to prevent lipohypertrophy 1, 2
• Recognition and treatment of hypoglycemia (symptoms, <70 mg/dL threshold, 15-gram carbohydrate rule) 1, 2
• Self-monitoring of blood glucose—at least four daily measurements (fasting, pre-meal, bedtime) during titration 1
• "Sick day" management: continue insulin even if not eating, check glucose every 4 hours, maintain hydration 1, 2
• Insulin storage and handling guidelines 1, 2

Common Pitfalls to Avoid

• Never delay insulin intensification in patients not achieving glycemic goals—this prolongs hyperglycemia exposure and increases complication risk 1
• Never discontinue metformin when starting or intensifying insulin unless contraindicated—this leads to higher insulin requirements and more weight gain 1
• Never continue sliding-scale insulin as monotherapy—this approach is definitively shown to be inferior and dangerous 2
• Never continue escalating basal insulin beyond 0.5–1.0 units/kg/day without addressing postprandial hyperglycemia—this causes overbasalization with increased hypoglycemia and suboptimal control 1

Alternative Consideration: GLP-1 Receptor Agonist

• For patients with established cardiovascular disease, heart failure, or chronic kidney disease, consider adding a GLP-1 receptor agonist (e.g., semaglutide) to the basal insulin regimen instead of prandial insulin 1, 5
• GLP-1 receptor agonists provide comparable or better HbA1c reduction with lower hypoglycemia risk and weight loss rather than weight gain 1, 6
• However, given the severity of hyperglycemia (A1c 9.9%), immediate basal-bolus insulin therapy is the most effective approach to rapidly achieve glycemic targets 1