What is the recommended dosage of Lantus (insulin glargine) 100U/1ML subcutaneous solution from a 10ML vial?

Lantus (Insulin Glargine) 100U/1ML Dosing Guidelines

Initial Starting Dose

For insulin-naive patients with type 2 diabetes, start Lantus at 10 units once daily or 0.1-0.2 units/kg body weight once daily, administered at the same time each day. 1

Type 2 Diabetes - Standard Initiation

• Begin with 10 units once daily for most patients with moderate hyperglycemia 1
• Alternatively, use 0.1-0.2 units/kg/day for weight-based dosing 1
• Continue metformin unless contraindicated, and possibly one additional non-insulin agent 1
• Administer at the same time each day for consistency 1

Type 2 Diabetes - Severe Hyperglycemia

• For patients with blood glucose ≥300-350 mg/dL and/or A1C ≥10-12% with symptomatic or catabolic features, start with basal-bolus insulin immediately rather than basal insulin alone 1
• For marked hyperglycemia with A1C ≥9%, consider more aggressive starting doses of 0.3-0.4 units/kg/day 1

Type 1 Diabetes Dosing

• Total daily insulin requirement: 0.4-1.0 units/kg/day, with 0.5 units/kg/day typical for metabolically stable patients 1
• Divide 40-50% as Lantus (basal) once daily and 50-60% as rapid-acting insulin (prandial) divided among meals 1
• Patients in honeymoon phase or with residual beta-cell function may require lower doses of 0.2-0.6 units/kg/day 1
• Higher doses often needed during puberty, pregnancy, and medical illness 1

Dose Titration Algorithm

Increase the dose by 2-4 units every 3 days until fasting blood glucose reaches 80-130 mg/dL. 1

Specific Titration Steps

• If fasting glucose is 140-179 mg/dL: increase by 2 units every 3 days 1
• If fasting glucose is ≥180 mg/dL: increase by 4 units every 3 days 1
• If more than 2 fasting glucose values per week are <80 mg/dL: decrease by 2 units 1
• If hypoglycemia occurs without clear cause: reduce dose by 10-20% immediately 1

Monitoring During Titration

• Daily fasting blood glucose monitoring is essential during titration 1
• Assess adequacy of insulin dose at every clinical visit 1
• Equip patients with self-titration algorithms based on self-monitoring 1

Critical Threshold: When to Stop Escalating Basal Insulin

When basal insulin exceeds 0.5 units/kg/day and approaches 1.0 units/kg/day, add prandial insulin rather than continuing to escalate basal insulin alone. 1

Signs of Overbasalization

• Basal insulin dose >0.5 units/kg/day 1
• Bedtime-to-morning glucose differential ≥50 mg/dL 1
• Hypoglycemia episodes 1
• High glucose variability 1

Adding Prandial Insulin

• Start with 4 units of rapid-acting insulin before the largest meal or 10% of current basal dose 1
• Increase prandial insulin by 1-2 units or 10-15% every 3 days based on postprandial glucose readings 1
• Consider adding a GLP-1 receptor agonist as an alternative to minimize hypoglycemia and weight gain 1

Special Populations Requiring Dose Adjustments

Hospitalized Patients

• For insulin-naive or low-dose insulin patients: 0.3-0.5 units/kg total daily dose, with half as basal insulin 1
• For patients on high-dose home insulin (≥0.6 units/kg/day): reduce total daily dose by 20% to prevent hypoglycemia 1
• For high-risk patients (elderly >65 years, renal failure, poor oral intake): use lower doses of 0.1-0.25 units/kg/day 1

Patients with Retinopathy or Renal Impairment

• Retinopathy: starting dose 0.120 U/kg/day 2
• eGFR <60 mL/min/1.73 m²: starting dose 0.114 U/kg/day 2

Women and Patients on Sulfonylureas

• Women: slightly decreased starting dose of 0.135 U/kg/day 2
• Patients with sulfonylureas: 0.132 U/kg/day 2

Common Pitfalls to Avoid

• Never delay insulin initiation in patients not achieving glycemic goals with oral medications 1
• Do not continue escalating basal insulin beyond 0.5-1.0 units/kg/day without addressing postprandial hyperglycemia—this leads to overbasalization, suboptimal control, and increased hypoglycemia risk 1
• Do not mix or dilute Lantus with any other insulin or solution due to its low pH 1
• Always reduce home insulin doses by 20% when admitting patients on high-dose insulin (≥0.6 units/kg/day) to prevent hypoglycemia 1
• Continue metformin when adding or intensifying insulin therapy unless contraindicated 1

Administration Guidelines

• Lantus can be administered at any time of day but must be at the same time each day 3
• In labile type 1 diabetes, it may be most effective given as two daily injections 3
• In obese, insulin-resistant patients requiring high volumes, consider two separate doses 3
• Do not administer intravenously or mix with other insulins 1