Converting Tresiba (Insulin Degludec) 16 Units Twice Daily to Solostar (Insulin Glargine)
When converting from Tresiba (insulin degludec) 16 units twice daily to Solostar (insulin glargine), the recommended approach is to use a total daily dose of 26 units of insulin glargine once daily (80% of the total Tresiba dose of 32 units).
Understanding the Conversion Process
- Tresiba (insulin degludec) is an ultra-long-acting basal insulin with a half-life of >25 hours, providing a more stable and evenly distributed glucose-lowering effect across a 24-hour period compared to insulin glargine 1
- When converting from twice-daily basal insulin to once-daily insulin glargine, the total daily dose should be reduced to approximately 80% of the current total daily dose 2
Calculation for This Specific Case
- Current regimen: Tresiba 16 units twice daily = 32 units total daily dose
- Recommended conversion: 32 units × 80% = 25.6 units (round to 26 units) of insulin glargine once daily 2
Rationale for Dose Reduction
- The 80% conversion factor accounts for differences in pharmacokinetic profiles between insulin types 2
- Insulin degludec has a longer half-life (>25 hours) compared to insulin glargine (approximately 12 hours), requiring adjustment when switching between these insulins 1
- Reducing the dose helps minimize the risk of hypoglycemia during the transition period 2
Administration Considerations
- Insulin glargine (Solostar) should be administered once daily at the same time each day 2
- Morning dosing may be preferred if the patient previously experienced nocturnal hypoglycemia with twice-daily basal insulin 2
Post-Conversion Monitoring and Adjustment
- Monitor fasting plasma glucose (FPG) closely after the switch 2
- Consider using an evidence-based titration algorithm: increase dose by 2 units every 3 days until reaching FPG goal without hypoglycemia 2
- If hypoglycemia occurs, reduce the dose by 10-20% 2
- Assess adequacy of insulin dose at every follow-up visit 2
Special Considerations
- Watch for signs of overbasalization: elevated bedtime-to-morning glucose differential, hypoglycemia, or high glucose variability 2
- If A1C remains above target after optimizing basal insulin, consider adding prandial insulin or a GLP-1 receptor agonist 2
- Studies have shown that switching from twice-daily glargine or detemir to once-daily degludec can improve glycemic control and reduce hypoglycemia risk 3, suggesting that the reverse transition should be monitored carefully
Remember that this conversion is an initial recommendation, and the dose may need to be adjusted based on individual patient response to achieve optimal glycemic control.