What is the typical starting dose of Lantus (insulin glargine) 100U/1ML Subcutaneous Solution for a patient with diabetes?

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

Type 2 Diabetes: Standard 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, administered at the same time each day. 1, 2

• Continue metformin unless contraindicated, and possibly one additional non-insulin agent when initiating basal insulin 1, 3
• For patients with more severe hyperglycemia (A1C ≥9% or blood glucose ≥300-350 mg/dL), consider higher starting doses of 0.3-0.4 units/kg/day 1
• Patients with A1C ≥10-12% with symptomatic or catabolic features require immediate basal-bolus insulin therapy, not basal insulin alone 1

Type 1 Diabetes: Starting Dose

For type 1 diabetes, the total daily insulin requirement is typically 0.5 units/kg/day, with approximately 50% given as Lantus (basal) and 50% as rapid-acting insulin (prandial) divided among meals. 1, 2

• Total daily insulin requirements range from 0.4 to 1.0 units/kg/day for type 1 diabetes 1, 2
• Higher doses are required immediately following diabetic ketoacidosis presentation 2
• Patients in the honeymoon phase may require lower doses of 0.2-0.6 units/kg/day 1

Dose Titration Algorithm

Increase Lantus by 2 units every 3 days if fasting glucose is 140-179 mg/dL, or by 4 units every 3 days if fasting glucose is ≥180 mg/dL, until reaching target fasting glucose of 80-130 mg/dL. 1, 2, 3

• Daily fasting blood glucose monitoring is essential during titration 1
• If hypoglycemia occurs without clear cause, reduce the dose by 10-20% immediately 1
• If more than 2 fasting glucose values per week are <80 mg/dL, decrease the dose by 2 units 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 Lantus alone. 1

• Clinical signals of "overbasalization" include: basal dose >0.5 units/kg/day, bedtime-to-morning glucose differential ≥50 mg/dL, hypoglycemia, and high glucose variability 1
• Start prandial insulin with 4 units of rapid-acting insulin before the largest meal, or use 10% of the current basal dose 1
• Continuing to increase basal insulin beyond this threshold leads to suboptimal control and increased hypoglycemia risk 1

Special Populations

Hospitalized Patients

• For insulin-naive or low-dose insulin patients: start with 0.3-0.5 units/kg/day 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
• High-risk patients (elderly >65 years, renal failure, poor oral intake): use lower doses of 0.1-0.25 units/kg/day 1

Patients on Enteral/Parenteral Feeding

• A reasonable starting point is 10 units of insulin glargine every 24 hours 1
• Basal insulin needs are typically 30-50% of total daily insulin requirement 1

Administration Guidelines

Lantus should be administered subcutaneously once daily at the same time each day. 4, 5

• Can be given at bedtime, in the morning, or at any convenient time for the patient 4
• In labile type 1 diabetes, twice-daily dosing may be more effective 4
• Do not dilute or mix Lantus with any other insulin or solution due to its low pH 1
• Proper injection technique and site rotation are essential for consistent absorption 3

Common Pitfalls to Avoid

• Do not delay insulin initiation in patients not achieving glycemic goals with oral medications—this prolongs hyperglycemia exposure and increases complication risk 1
• Do not continue escalating basal insulin beyond 0.5-1.0 units/kg/day without addressing postprandial hyperglycemia with prandial insulin 1
• Do not abruptly discontinue metformin when starting insulin—continue unless contraindicated 1
• Do not rely solely on correction insulin—scheduled basal-bolus regimens are superior to sliding scale monotherapy 1