How should the basal and bolus insulin doses be adjusted for a patient on Toujeo (insulin glargine) 65 units nightly and Novolog (insulin aspart) 25 units three times daily who has persistent hyperglycemia (blood glucose around 300 mg/dL)?

Insulin Dose Adjustment for Persistent Hyperglycemia

Immediately increase the Toujeo basal insulin dose by 10-20% (approximately 6-13 units, bringing it to 71-78 units nightly) and simultaneously increase each Novolog bolus dose by 10-15% (approximately 3-4 units, bringing each dose to 28-29 units TID), then reassess glucose patterns in 3-4 days. 1

Rationale for Dose Adjustments

Your patient is experiencing severe hyperglycemia (BG ~300 mg/dL) despite substantial insulin doses, indicating significant insulin resistance or inadequate dosing. The 2025 ADA Standards of Care explicitly address this scenario 1:

• For basal insulin titration: When A1C remains above goal, increase doses by 10-20% for persistent hyperglycemia
• Titration frequency: Adjust basal insulin no more frequently than every 3-4 days 2
• For prandial insulin: Increase by 1-2 units or 10-15% when glucose remains elevated 1

Specific Adjustment Protocol

Basal Insulin (Toujeo) Adjustment:

• Current dose: 65 units
• Increase to 71-78 units (10-20% increase)
• Monitor fasting plasma glucose specifically
• Continue titrating every 3-4 days until fasting glucose reaches 80-130 mg/dL 1

Bolus Insulin (Novolog) Adjustment:

• Current dose: 25 units TID (75 units total daily bolus)
• Increase each dose to 28-29 units TID (10-15% increase per dose)
• Monitor pre-meal and 2-hour postprandial glucose values
• Adjust individual meal doses based on which meals show highest postprandial excursions 1

Critical Considerations

Check for Overbasalization

With blood glucose persistently at 300 mg/dL despite 65 units of basal insulin, evaluate:

• Bedtime-to-morning glucose differential: If minimal change overnight, basal may be adequate but bolus insufficient
• Postprandial-to-preprandial differential: Large differences indicate inadequate prandial coverage 1

This patient's total daily insulin dose is 140 units (65 basal + 75 bolus), representing a 46% basal/54% bolus split. Recent evidence challenges the traditional 50-50 rule, showing many patients with type 2 diabetes require <50% basal insulin 3. Your patient may actually need proportionally more bolus insulin.

Important Toujeo-Specific Factor

Toujeo (U-300 insulin glargine) requires higher unit doses than standard U-100 insulins to achieve equivalent glycemic control 2, 4. If this patient was recently switched from another basal insulin, the dose may be genuinely insufficient. Research shows patients on Toujeo require significantly more units daily than those on Lantus (U-100) for equivalent efficacy 4.

Monitoring Requirements

• Increase glucose monitoring frequency during dose adjustments 2
• Check fasting glucose daily to guide basal titration
• Check pre-meal and 2-hour postprandial values to guide bolus adjustments
• Watch for hypoglycemia, though unlikely at current glucose levels
• If hypoglycemia occurs without clear cause, reduce the corresponding insulin dose by 10-20% 1

Alternative Considerations

If glucose remains >300 mg/dL after appropriate dose escalation:

1. Consider adding GLP-1 receptor agonist if not already prescribed - the 2025 ADA guidelines specifically recommend this combination when A1C remains above goal 1
2. Evaluate for insulin resistance factors: infections, steroid use, significant weight gain, non-adherence
3. Assess injection technique: lipodystrophy, proper rotation, expired insulin
4. Rule out type 1 diabetes if this is a new diagnosis with very high glucose despite high insulin doses 1

Common Pitfalls to Avoid

• Do NOT use sliding-scale insulin alone - this patient needs scheduled basal-bolus therapy 5
• Do NOT split the Toujeo dose - it is designed for once-daily administration 2
• Do NOT delay titration - with glucose at 300 mg/dL, aggressive upward titration is warranted and safe 1
• Do NOT assume the 50-50 basal-bolus ratio is optimal - individual needs vary significantly 3