Correction Dose for Pre-Meal Glucose of 350 mg/dL
For a pre-meal glucose of 350 mg/dL, administer 4 units of lispro as a correction dose. 1
Evidence-Based Dosing Protocol
The American Diabetes Association provides explicit guidance for simplified correction insulin in patients requiring adjustment of prandial insulin regimens:
- When pre-meal glucose exceeds 350 mg/dL (19.4 mmol/L), give 4 units of short- or rapid-acting insulin 1
- For pre-meal glucose between 250-350 mg/dL (13.9-19.4 mmol/L), give 2 units 1
- This simplified sliding scale should be used temporarily while adjusting the underlying basal-prandial regimen 1
Critical Timing Considerations
Lispro must be administered 0-15 minutes before the meal for optimal postprandial glucose control 1, 2. Research demonstrates that in hyperglycemic patients (glucose >250 mg/dL), administering lispro 15 minutes before meals significantly improves postprandial glucose excursion compared to injection at mealtime 3. The rapid absorption profile of lispro—with onset at 0.25-0.5 hours, peak at 1-3 hours, and duration of 3-5 hours—makes pre-meal timing essential 4, 5, 6.
Beyond Immediate Correction
This 4-unit correction dose addresses the acute hyperglycemia, but if correction doses are needed daily, the underlying insulin regimen requires adjustment 1:
- Increase basal insulin by 2 units every 3 days if fasting glucose is 140-179 mg/dL 1
- Increase basal insulin by 4 units every 3 days if fasting glucose ≥180 mg/dL 1
- Target fasting glucose of 90-150 mg/dL (5.0-8.3 mmol/L) 1
- Stop the sliding scale when correction doses are no longer needed daily 1
Safety Monitoring
- Monitor for hypoglycemia 1-3 hours post-injection when lispro peaks 1
- Never use rapid-acting insulin at bedtime as a sole correction dose, as this markedly increases nocturnal hypoglycemia risk 1, 7
- If hypoglycemia occurs without clear cause, reduce the implicated insulin dose by 10-20% 7
Common Pitfall to Avoid
Do not rely solely on correction doses to manage persistent hyperglycemia. Sliding scale insulin as monotherapy is explicitly condemned by all major diabetes guidelines because it treats hyperglycemia reactively rather than preventing it, leading to dangerous glucose fluctuations 7. Only 38% of patients achieve adequate control with sliding scale alone versus 68% with proper basal-bolus therapy 7. The need for daily correction doses signals inadequate scheduled insulin coverage that must be addressed through systematic titration of basal and prandial insulin 1, 7.