• Indications
  1. Type 1 Diabetes Mellitus
    1. Basal insulin for those not using an Insulin Pump (or for emergency use when Insulin Pump fails)
  2. Type 2 Diabetes Mellitus with Insulin Resistance refractory to non-Insulin therapy
  • Mechanism
  1. See Insulin
  • Medications
  • Insulin Glargine U-100 (Lantus, Basaglar, Semglee, Rezvoglar)
  1. Insulin Glargine U-100 is the standard Insulin Glargine concentration (100 units/ml)
    1. Do not confuse with Insulin Glargine U-300 (3 fold higher concentration)
  2. Pharmacokinetics
    1. Most closely matches 24 hour coverage
    2. Onset: 1-2 hours
    3. Duration: 21 to 24 hours
    4. Peak: No peak (flat action curve mimics continuous Insulin Infusion)
  3. Several products are considered biosimilar and interchangeable with Lantus
    1. Allows pharmacists to auto-substitute less expensive formulations for Lantus
    2. Semglee (Glargine-yfgn U-100) is considered an interchangeable biosimilar as of 2021 in U.S.
    3. Rezvoglar (Glargine-aglr) is considered an interchangeable biosimilar
    4. However, Basaglar is not considered a biosimilar (cannot be auto-substituted)
    5. (2021) Presc Lett 28(9): 51
    6. (2025) Presc Lett 32(1):2-3
  • Dosing
  • Insulin Glargine (Lantus)
  1. See Insulin Dosing
  2. See Insulin Dosing in Type I Diabetes
  3. See Insulin Dosing in Type II Diabetes
  4. Insulin Glargine is injected subcutaneously (SQ)
  5. Typical daily dosing
    1. Basal insulins are injected subcutaneously (SQ)
    2. Total daily Insulin
      1. Type 1 Diabetes: 0.3 to 0.5 units/kg (up to 0.5 to 1.0 units/kg in children)
      2. Type 2 Diabetes: 1 to 1.5 units/kg
    3. Basal insulin dose
      1. Give 50% in Type 2 DM (30% in Type 1 DM) of total daily dose as Basal insulin once daily SQ
      2. Give remaining 50% of total Insulin daily units as Bolus Insulin divided over 3 meals
        1. In type 2 diabetes, Basal insulin is often started without Bolus Insulin
  6. Starting dose in Type 2 Diabetes Mellitus (no prior Insulin)
    1. Hemoglobin A1C <8%: 0.1 units/kg
    2. Hemoglobin A1C >8-10%: 0.2 units/kg
    3. Hemoglobin A1C >10%: 0.3 units/kg
  7. Common starting dose (use units/kg as above instead)
    1. Type I Diabetes: 10 Units at bedtime
    2. Type II Diabetes: 10-14 Units at bedtime
  8. Conversion from other Long-Acting Insulin
    1. NPH/ultralente at bedtime: start Lantus at same dose
      1. Consider starting Lantus at 80% of prior NPH dose
    2. NPH twice daily: Start Lantus at 80% of total daily NPH dose
  9. Adjustment based on Fasting plasma Glucose (FPG)
    1. Typical adjustment is 1 to 2 units (or 5 to 10%) once to twice weekly
    2. Protocol 1
      1. FPG <70 mg/dl for 3 days: Decrease Lantus 1-2 units
      2. FPG 140-250 for 3 days: Increase Lantus 2-4 units
      3. FPG >250 for 3 days: Increase Lantus 4-8 units
    3. Protocol 2
      1. FPG <80 for 3 days: Decrease Lantus by 2 units
      2. FPG 100-120 for 3 days: Increase Lantus by 2 units
      3. FPG 120-140 for 3 days: Increase Lantus by 4 units
      4. FPG 140-180 for 3 days: Increase Lantus by 6 units
      5. FPG >180 for 3 days: Increase Lantus by 8 units
  10. Timing of dose for Lantus
    1. Studies gave Lantus at bedtime to avoid confusion
    2. Lantus is most effective if given in the morning
    3. May require divided dosing twice daily to maintain basal rate (21 to 24 hour duration)
  • Adverse Effects
  1. See Insulin
  2. Less nocturnal Hypoglycemia than other Insulins
  3. Lower post-prandial Glucose
  • Safety
  1. Insulin is considered safe in pregnancy and Lactation