Insulin Infusion Adjustment Rate When Transitioning Off IV Insulin After DKA
Administer subcutaneous basal insulin 2-4 hours before discontinuing the IV insulin infusion, then continue the IV infusion at the current rate during this overlap period before stopping it completely. 1, 2
Critical Timing Requirements
The transition requires a mandatory overlap period to prevent rebound hyperglycemia and recurrent DKA:
- Give the first dose of subcutaneous basal insulin (glargine or detemir) 2-4 hours before stopping the IV insulin infusion. 1, 2, 3
- Continue the IV insulin infusion at its current rate throughout this 2-4 hour overlap period without any rate adjustment. 2
- Only after the overlap period is complete should you discontinue the IV infusion entirely. 1, 3
This approach is emphasized across multiple guidelines because stopping IV insulin before administering subcutaneous insulin causes rebound hyperglycemia and recurrent DKA—a critical pitfall to avoid. 3
Prerequisites Before Transition
Ensure DKA has resolved before initiating the transition. The 2025 American Diabetes Association guidelines define resolution as: 1
Recent research suggests that transitioning at an anion gap >12 mEq/L may be safe in select patients, with one 2024 study showing no difference in transition success between patients with AG ≤12 versus >12 mEq/L (7% vs 4% failure rate, P=0.66). 4 However, given the established guideline threshold and the small sample size of this single study, adhering to the AG ≤12 mEq/L criterion remains the safest approach. 1
Calculating Subcutaneous Insulin Doses
Calculate the total units of IV insulin infused over the previous 24 hours when glucose has been stable to determine your subcutaneous dosing: 2, 3
- 50% of the 24-hour IV insulin total = once-daily basal insulin (glargine or detemir) given subcutaneously 2, 3
- Remaining 50% divided by 3 = rapid-acting insulin (lispro, aspart, or glulisine) before each meal 2, 3
For example, if a patient received 48 units of IV insulin over 24 hours: give 24 units of glargine once daily and 8 units of rapid-acting insulin before each of three meals. 2, 3
Monitoring During and After Transition
Check capillary blood glucose every 2-4 hours initially after transition, with more frequent monitoring if glucose becomes unstable. 1, 2
Monitor serum potassium closely as insulin drives potassium intracellularly, maintaining levels between 4-5 mEq/L. 1, 2 The 2025 ADA guidelines specify giving potassium in each liter of IV fluid as needed during this period. 1
Common Pitfalls to Avoid
- Never stop IV insulin before administering subcutaneous basal insulin—this single error causes the majority of transition failures with rebound hyperglycemia and recurrent DKA. 2, 3
- Never use correction-only (sliding scale) insulin without basal coverage—this approach leads to worse outcomes and higher complication rates. 3
- Never calculate subcutaneous doses based on unstable IV insulin rates—wait until glucose has been stable, ideally <180 mg/dL, for at least 4-6 hours before calculating the 24-hour total. 2, 3
The evidence consistently shows that when this overlap protocol is followed, transition success rates exceed 90%, whereas omitting the overlap period substantially increases failure rates. 4, 5