What is the safest method to convert a patient who is currently taking Levemir (insulin detemir) to Basaglar (insulin glargine‑U100), including the initial basal dose and subsequent titration strategy?

Converting from Levemir to Basaglar: Evidence-Based Protocol

Convert Levemir to Basaglar on a 1:1 unit basis for most patients, but reduce the converted dose by 10–20% if the patient was previously on twice-daily Levemir or has high-risk features such as age >65 years, renal impairment, or history of severe hypoglycemia. 1

Standard Conversion Algorithm

For Patients on Once-Daily Levemir

• Calculate the total daily Levemir dose and convert unit-for-unit to once-daily Basaglar 1
• Administer Basaglar at the same time each day, typically with the evening meal or at bedtime 1

For Patients on Twice-Daily Levemir

• Sum both daily doses of Levemir to determine the total daily dose 1
• Reduce the total by 10–20% when converting to once-daily Basaglar due to differences in dosing requirements between the two insulins 1
• This dose reduction accounts for the fact that patients on twice-daily Levemir often require higher total daily doses compared to once-daily long-acting analogs 1

High-Risk Patient Modifications

Automatically reduce the converted dose by 10–20% for patients with any of the following characteristics: 1

• Elderly patients (>65 years) 1
• Renal impairment 1
• History of severe hypoglycemia 1
• Poor oral intake or acute illness 1

Post-Conversion Monitoring Protocol

First 1–2 Weeks

• Daily fasting blood glucose monitoring is essential to assess adequacy of the new dose 1
• Make dose adjustments every 3 days based on fasting glucose values, targeting 80–130 mg/dL 1

Titration Algorithm

• If fasting glucose is 140–179 mg/dL: increase the dose by 2 units every 3 days 1
• If fasting glucose is ≥180 mg/dL: increase the dose by 4 units every 3 days 1
• If hypoglycemia occurs: reduce the dose immediately by 10–20% and reassess the conversion 1

Critical Administration Details

• Do not dilute or mix Basaglar (insulin glargine) with any other insulin or solution due to its low pH diluent 1
• Basaglar and Lantus are both insulin glargine U-100 formulations and are considered interchangeable in terms of dosing 1
• Administer at the same time each day for optimal glycemic stability 1

Common Pitfalls to Avoid

• Do not assume a 1:1 conversion is safe for all patients—those on twice-daily Levemir or with high-risk features require dose reduction 1
• Do not delay post-conversion monitoring—the first 1–2 weeks are critical for identifying inadequate dosing or hypoglycemia risk 1
• Do not continue escalating basal insulin beyond 0.5–1.0 units/kg/day without addressing postprandial hyperglycemia, as this leads to overbasalization 2
• Do not mix Basaglar with other insulins in the same syringe, as this alters its pharmacokinetic profile 1

Expected Outcomes

• Most patients achieve equivalent glycemic control with Basaglar compared to Levemir when properly converted 3, 4
• Studies show no significant difference in 24-hour glucose control between insulin detemir and insulin glargine when dosed appropriately 3, 4
• The mean dosage required is typically similar between the two insulins when titrated to the same fasting glucose target 4