Lantus Dose Adjustment for Overnight Hyperglycemia
Immediate Dose Increase Required
Increase Lantus from 10 units to 14 units tonight, then continue increasing by 4 units every 3 days until fasting blood glucose consistently reaches 80-130 mg/dL. 1
Titration Algorithm
For a patient with overnight blood glucose of 247 mg/dL (≥180 mg/dL), the evidence-based approach is aggressive titration:
- Increase basal insulin by 4 units every 3 days when fasting glucose is ≥180 mg/dL 1, 2
- Target fasting plasma glucose: 80-130 mg/dL 1
- If fasting glucose drops to 140-179 mg/dL during titration, reduce increment to 2 units every 3 days 1
Daily Monitoring Requirements
- Check fasting blood glucose every morning during the titration phase 1
- Record all fasting glucose values to guide dose adjustments every 3 days 1
- If hypoglycemia occurs (glucose <70 mg/dL) without clear cause, reduce dose by 10-20% immediately 1
Critical Threshold to Monitor
Watch for overbasalization when Lantus exceeds 0.5 units/kg/day (approximately 35-40 units for an average adult). 1, 2 Clinical signals include:
- Basal dose >0.5 units/kg/day 1
- Bedtime-to-morning glucose differential ≥50 mg/dL 1
- Episodes of hypoglycemia 1
- High glucose variability throughout the day 1
When basal insulin approaches this threshold without achieving glycemic targets, adding prandial insulin becomes more appropriate than continuing to escalate basal insulin alone. 1, 2
Foundation Therapy
- Continue metformin (unless contraindicated) when intensifying insulin therapy, as this combination provides superior glycemic control with reduced insulin requirements 1, 2
- Maximum effective metformin dose is up to 2000-2550 mg daily 2
Expected Timeline
- Reassess every 3 days during active titration 1
- Most patients require 2-4 weeks of systematic titration to reach fasting glucose targets 3
- Check HbA1c after 3 months to determine if additional intensification is needed 1
Common Pitfall to Avoid
Do not delay dose increases or use smaller increments than recommended. The 4-unit increment for glucose ≥180 mg/dL is evidence-based and safe when properly monitored. 1 Timid titration unnecessarily prolongs hyperglycemia exposure and increases complication risk. 1