Insulin Titration After Starting 0.5 U/kg/day in Type 1 Diabetes
After initiating insulin at 0.5 U/kg/day (split 50% basal and 50% prandial), increase the basal insulin by 2-4 units every 3 days based on fasting glucose levels until reaching 80-130 mg/dL, while adjusting prandial insulin by 1-2 units every 3 days based on postprandial glucose readings. 1, 2
Initial Distribution and Baseline Dosing
- The starting dose of 0.5 units/kg/day should be divided with approximately 50% as basal insulin (given once daily) and 50% as prandial insulin (divided among three meals). 1, 2
- This 50:50 split represents the foundation for metabolically stable patients with type 1 diabetes. 1, 2
Basal Insulin Titration Protocol
Adjust basal insulin based on fasting plasma glucose using this specific algorithm: 1, 2, 3
- If fasting glucose is 140-179 mg/dL: increase basal insulin by 2 units every 3 days 1, 3
- If fasting glucose is ≥180 mg/dL: increase basal insulin by 4 units every 3 days 1, 3
- Target fasting plasma glucose: 80-130 mg/dL 1, 3
- If hypoglycemia occurs, reduce the dose by 10-20% immediately 1, 3
Prandial Insulin Titration Protocol
- Adjust prandial insulin by 1-2 units or 10-15% every 3 days based on 2-hour postprandial glucose readings. 2, 3
- Each meal's insulin dose should be titrated independently based on the glucose response after that specific meal. 2
- Rapid-acting insulin analogs (aspart, lispro, glulisine) should be administered 0-15 minutes before meals for optimal postprandial control. 1, 4, 5
Critical Threshold: When to Stop Escalating Basal Insulin
When basal insulin exceeds 0.5 units/kg/day and approaches 1.0 units/kg/day, add or intensify prandial insulin rather than continuing to escalate basal insulin alone. 1, 2, 3
This threshold prevents "overbasalization," which manifests as: 2, 3
- Bedtime-to-morning glucose differential ≥50 mg/dL
- Hypoglycemia episodes
- High glucose variability despite adequate fasting glucose control
Special Populations Requiring Higher Doses
Certain clinical situations demand doses exceeding the standard 0.5 units/kg/day: 1, 2
- Puberty: May require approaching or exceeding 1.0 units/kg/day 1, 2
- Pregnancy: Requires higher doses throughout gestation 1, 2
- Acute illness/infection: May need 40-60% increase in total daily dose 2, 3
- Immediately post-DKA: Requires higher weight-based dosing than standard 2
Monitoring Requirements During Titration
- Daily fasting blood glucose monitoring is essential during the titration phase. 1, 3
- Check pre-meal and 2-hour postprandial glucose to guide prandial insulin adjustments. 1, 3
- Reassess adequacy of insulin doses at every clinical visit, specifically looking for signs of overbasalization. 3
- Measure HbA1c every 3 months during intensive titration periods. 3
Common Pitfalls to Avoid
- Do not wait longer than 3 days between basal insulin adjustments in stable patients, as this unnecessarily prolongs time to glycemic targets. 3
- Do not continue escalating basal insulin beyond 0.5-1.0 units/kg/day without addressing postprandial hyperglycemia with prandial insulin. 2, 3
- Do not use sliding scale insulin as monotherapy—scheduled basal-bolus regimens are superior. 3
- Do not blame inadequate prandial coverage for fasting hyperglycemia—fasting glucose reflects basal insulin adequacy, not meal coverage. 3
Carbohydrate Counting and Advanced Adjustments
- Educate patients on matching prandial insulin doses to carbohydrate intake using carbohydrate-to-insulin ratios (typically starting at 1:10-1:15). 1, 2
- Calculate insulin sensitivity factor (ISF) using the formula: 1500 ÷ Total Daily Dose to determine correction doses. 2, 3
- Adjust premeal insulin for anticipated physical activity, as exercise increases insulin sensitivity. 1