Insulin Dose Adjustment Recommendations
Immediate Lantus Dose Adjustment
Increase your Lantus from 19 units to 23 units tonight, and continue increasing by 4 units every 3 days until your overnight (fasting) blood glucose consistently reaches 80-130 mg/dL. 1
Your overnight blood glucose of 171 mg/dL indicates inadequate basal insulin coverage. When fasting glucose is ≥180 mg/dL, the dose should be increased by 4 units every 3 days, and when it's 140-179 mg/dL (like your 171 mg/dL), increase by 2-4 units every 3 days until reaching the target of 80-130 mg/dL. 1, 2
Carbohydrate Coverage Adjustment
Your current carb ratio of 1:8 is too weak—tighten it to 1:10 or 1:12 and add prandial insulin coverage immediately. 1
The post-meal blood glucose readings of 247 mg/dL and 182 mg/dL demonstrate that your carbohydrate coverage is insufficient. A common starting insulin-to-carbohydrate ratio is 1 unit per 10-15 grams of carbohydrate. 1 You can calculate a more precise ratio using the formula: 450 ÷ total daily dose (TDD). 1
Critical Threshold Warning
Monitor your total daily insulin dose carefully—when your Lantus exceeds approximately 35-40 units (0.5 units/kg/day for a typical adult), you'll need to add structured prandial insulin rather than continuing to escalate basal insulin alone. 1, 2
Signs you're approaching this threshold include:
- Basal insulin dose >0.5 units/kg/day 1, 2
- Large overnight glucose drop (≥50 mg/dL from bedtime to morning) 1, 2
- Episodes of hypoglycemia 1, 2
- High glucose variability throughout the day 1, 2
Structured Prandial Insulin Initiation
Start with 4 units of rapid-acting insulin (like Humalog or NovoLog) before your largest meal, administered 0-15 minutes before eating. 1
Alternatively, use 10% of your current basal dose (approximately 2 units based on 19 units Lantus). 1 Increase this prandial dose by 1-2 units every 3 days based on your 2-hour post-meal glucose readings, targeting levels <180 mg/dL. 1
Daily Monitoring Requirements
Check your fasting blood glucose every morning and record all values to guide dose adjustments every 3 days. 1, 2
Also check pre-meal glucose before administering prandial insulin to calculate correction doses and prevent hypoglycemia. 3 Target pre-meal glucose should be 90-150 mg/dL. 3
Hypoglycemia Management
If any blood glucose reading falls below 70 mg/dL, immediately reduce your insulin dose by 10-20% and treat with 15 grams of fast-acting carbohydrate. 1
Always carry glucose tablets or another fast-acting carbohydrate source. 4 Recheck glucose in 15 minutes and repeat treatment if needed. 4
Foundation Therapy Verification
Ensure you're taking metformin (unless contraindicated) at maximum tolerated dose, up to 2000-2550 mg daily. 1
Metformin should be continued when adding or intensifying insulin therapy, as this combination reduces total insulin requirements and provides superior glycemic control with less weight gain. 1
Common Pitfalls to Avoid
Never continue escalating Lantus beyond 0.5-1.0 units/kg/day without addressing postprandial hyperglycemia with prandial insulin—this leads to "overbasalization" with increased hypoglycemia risk and suboptimal control. 1, 2
Do not rely solely on correction insulin ("sliding scale") to manage high blood sugars—scheduled basal and prandial insulin doses must be adjusted based on patterns. 1 Never give rapid-acting insulin at bedtime, as this significantly increases nocturnal hypoglycemia risk. 1, 3
When to Contact Your Healthcare Provider
Contact your provider if:
- Fasting glucose remains >180 mg/dL after 2-3 weeks of titration 1
- Your Lantus dose exceeds 0.5 units/kg/day (approximately 35-40 units for most adults) without achieving fasting glucose targets 1, 2
- You experience any blood glucose <70 mg/dL 1
- Post-meal glucose consistently exceeds 180 mg/dL despite carb coverage adjustments 1