What is the initial dose of Lantus (insulin glargine) in diabetic ketoacidosis (DKA)?

Initial Lantus (Insulin Glargine) Dosing in Diabetic Ketoacidosis (DKA)

For patients with DKA, basal insulin (Lantus) should be initiated at 0.2 units/kg as a single dose during the transition from intravenous insulin to subcutaneous insulin, administered 2-4 hours before stopping the IV insulin infusion to prevent rebound hyperglycemia.

DKA Management Overview

DKA management follows a stepwise approach:

1. Initial stabilization with IV fluids and continuous IV insulin infusion
2. Resolution of ketoacidosis (defined as glucose <200 mg/dL, serum bicarbonate ≥18 mEq/L, venous pH ≥7.3)
3. Transition to subcutaneous insulin regimen

Initial IV Insulin Management

• Start with IV regular insulin bolus of 0.1-0.15 units/kg followed by continuous infusion at 0.1 units/kg/hour 1
• For mild DKA, subcutaneous insulin may be considered (0.1 units/kg after initial dose of 0.4-0.6 units/kg) 2
• Monitor blood glucose every 1-2 hours and electrolytes every 2-4 hours 1

Transition to Subcutaneous Insulin Including Lantus

The critical phase for Lantus initiation is during transition from IV to subcutaneous insulin:

1. Timing: Administer basal insulin (Lantus) 2-4 hours before discontinuing IV insulin 2
2. Dosing: 0.2 units/kg of Lantus as a single daily dose 3
3. Complementary insulin: Add rapid-acting insulin (0.2 units/kg initially) for meal coverage and correction 3

Evidence for Basal-Bolus Regimen

The American Diabetes Association guidelines (2024) emphasize that successful transition from IV to subcutaneous insulin requires administration of basal insulin 2-4 hours before stopping IV insulin to prevent recurrence of ketoacidosis and rebound hyperglycemia 2.

A recent study demonstrated that a combination of glargine (0.2 units/kg) and rapid-acting insulin (0.2 units/kg) was effective for transitioning from IV insulin, with 90% of patients achieving DKA resolution within 12 hours 3.

Advantages of Basal-Bolus with Lantus

Research shows that a basal-bolus regimen with glargine (Lantus) and rapid-acting insulin results in:

• Similar glycemic control to traditional NPH and regular insulin regimens
• Lower rates of hypoglycemia (15% vs 41% with NPH/regular insulin) 4
• Comparable efficacy in resolving DKA 5

Common Pitfalls to Avoid

1. Premature discontinuation of IV insulin: Abruptly stopping IV insulin without overlapping with subcutaneous basal insulin can lead to recurrent ketoacidosis

2. Inadequate basal coverage: Failure to provide adequate basal insulin during transition can cause rebound hyperglycemia

3. Delayed initiation of basal insulin: Waiting until complete resolution of DKA before starting basal insulin increases risk of metabolic decompensation

4. Inappropriate dosing: Using fixed doses rather than weight-based dosing may result in under or over treatment

Special Considerations

• For patients with new-onset diabetes, consider starting at the lower end of the dosing range
• For patients with established diabetes, consider their previous insulin requirements if known
• Patients using insulin pumps may require different transition protocols

By following this approach with appropriate Lantus dosing at 0.2 units/kg during transition from IV to subcutaneous insulin, patients with DKA can be safely and effectively managed with reduced risk of recurrent ketoacidosis or hypoglycemia.