What is the initial dosing for long-acting insulin (e.g., glargine (Lantus) or detemir (Levemir)) in patients starting therapy?

Initial Dosing of Long-Acting Insulin

Basal insulin should be initiated at 10 units per day or 0.1-0.2 units/kg of body weight for patients starting therapy. 1

Dosing Guidelines for Long-Acting Insulin

Initial Dosing

• Start with 10 units once daily or 0.1-0.2 units/kg/day 1, 2
• For insulin-naive patients with type 2 diabetes:
  • Administer once daily in the evening or at bedtime 3
  • Continue oral antidiabetic medications (particularly metformin) 1

Patient-Specific Considerations

• For elderly patients or those with renal failure: Consider lower starting doses (0.1 units/kg/day) to minimize hypoglycemia risk 2
• For patients with severe hyperglycemia (HbA1c ≥9% or fasting glucose ≥300-350 mg/dL): Consider starting insulin therapy earlier in the treatment algorithm 1
• For patients with symptomatic hyperglycemia or catabolic features: Consider basal-bolus insulin as the initial regimen 1

Titration Protocol

Self-Titration Method

• Adjust dose by 2 units once or twice weekly until fasting glucose target is reached 1, 4
• Target fasting glucose range: 80-130 mg/dL 4
• Decrease dose by 2 units if fasting glucose <80 mg/dL or hypoglycemic episodes occur 1

Clinic-Based Titration

• Increase dose by 2-4 units every 3-7 days based on self-monitored blood glucose readings 5
• For higher starting HbA1c levels (>8.5%), more aggressive titration may be needed 6

Choice of Long-Acting Insulin

Available Options

• Glargine (Lantus): Once daily dosing, typically at bedtime 1
• Detemir (Levemir): Can be administered once or twice daily 3
• Degludec: Once daily dosing with more flexible timing 1
• NPH insulin: Intermediate-acting option, may require twice-daily dosing 1

Considerations for Selection

• Newer long-acting analogs (glargine, detemir, degludec) have lower risk of nocturnal hypoglycemia compared to NPH insulin 1
• If cost is a concern, human NPH insulin may be a more affordable option 1

Monitoring and Follow-Up

• Monitor fasting blood glucose daily during initiation and titration 2
• Evaluate for signs of overbasalization (basal dose >0.5 units/kg with inadequate glucose control) 1
• Assess HbA1c after 3 months to determine if glycemic targets are being met 2
• If fasting glucose targets are achieved but HbA1c remains elevated, consider adding prandial insulin or GLP-1 receptor agonist 1

Common Pitfalls to Avoid

1. Delayed titration: Timely dose adjustment is critical for achieving glycemic targets 1
2. Overbasalization: Continuing to increase basal insulin beyond 0.5 units/kg/day without improvement in fasting glucose 1, 4
3. Ignoring hypoglycemia: Reduce dose if fasting glucose falls below 80 mg/dL or if nocturnal hypoglycemia occurs 1
4. Discontinuing oral agents: Metformin should generally be continued when initiating basal insulin 1
5. Inadequate patient education: Ensure proper injection technique and hypoglycemia management 2

By following these guidelines for initiating long-acting insulin therapy, clinicians can help patients achieve optimal glycemic control while minimizing the risk of adverse events such as hypoglycemia.