How do you adjust insulin doses based on glucose readings?

Insulin Adjustment Based on Glucose Readings

Insulin dosage should be adjusted based on regular glucose monitoring patterns, with basal insulin titrated according to fasting glucose values and prandial insulin adjusted based on pre- and post-meal readings.

Basal Insulin Adjustment

Basal insulin (long-acting) should be adjusted based on fasting glucose patterns:

• Initial dosing: Start with 10 units/day or 0.1-0.2 units/kg/day 1
• Titration algorithm: Adjust based on fasting glucose readings over 1 week 2
  • If 50% of fasting glucose values are above target (90-150 mg/dL): Increase dose by 2 units
  • If >2 fasting glucose values/week are <80 mg/dL: Decrease dose by 2 units

Prandial Insulin Adjustment

For patients on multiple daily injections with mealtime insulin:

• Initial dosing: Start at 4 units or 10% of basal dose before meals 1
• Titration approach: Adjust based on pre-meal and post-meal glucose patterns
  • If prandial insulin >10 units/dose: Consider decreasing by 50% and adding non-insulin agent 2
  • For pre-meal glucose >250 mg/dL: Add 2 units of rapid-acting insulin
  • For pre-meal glucose >350 mg/dL: Add 4 units of rapid-acting insulin 2

Simplified Insulin Regimens for Older Adults

For older adults or those with complex regimens, consider simplification:

• Change basal insulin timing from bedtime to morning 2
• Use 70% of total daily dose as basal insulin 2
• Avoid rapid-acting insulin at bedtime 2
• Target fasting glucose of 90-150 mg/dL (may adjust based on overall health) 2

Practical Considerations

Injection Technique

• Rotate injection sites within the same region (abdomen, thigh, or deltoid) to reduce lipodystrophy risk 3
• The abdomen has the fastest absorption rate, followed by arms, thighs, and buttocks 2
• Exercise increases insulin absorption from injection sites 2

Monitoring Frequency

• Adjust insulin doses weekly based on glucose patterns 4
• Use fasting glucose values to titrate basal insulin and both pre- and post-meal values for prandial insulin 5
• Increase monitoring frequency during illness, travel, or changes in routine 2

Hypoglycemia Prevention

• Carry at least 15g of fast-acting carbohydrate to treat hypoglycemia 2
• Reduce insulin doses during increased physical activity 2
• For patients prone to hypoglycemia, consider a more conservative approach with smaller correction doses (2-4 units) 1

Advanced Insulin Adjustment Methods

Two effective approaches for prandial insulin adjustment:

1. Simple Algorithm Method: Fixed dose adjustments based on pre-meal glucose values

   • Effective for patients who prefer simplicity 6

2. Carbohydrate Counting Method: Insulin-to-carbohydrate ratio

   • May result in lower total daily insulin dose and less weight gain 6
   • More flexible for varying meal sizes and content

Common Pitfalls to Avoid

• Stacking insulin doses: Avoid giving additional correction doses before previous dose has peaked 1
• Ignoring patterns: Adjust based on glucose patterns over several days, not single readings 4
• Inconsistent timing: Administer basal insulin at the same time daily 3
• Neglecting site rotation: Poor rotation leads to lipohypertrophy and erratic absorption 5
• Abrupt regimen changes: Increase monitoring frequency during insulin regimen changes 3

Weekly insulin adjustments based on glucose patterns are sufficient for safe and effective therapy, with software-assisted adjustments showing comparable results to physician adjustments in over 95% of cases 7, 4.