What is the initial dose of Lantus (insulin glargine) for an adult patient with type 2 diabetes and no prior insulin use?

Starting Lantus Dose for Type 2 Diabetes

For insulin-naive adults with type 2 diabetes, start Lantus at 10 units once daily OR 0.2 units/kg body weight once daily, administered at the same time each day. 1, 2, 3

Initial Dosing Algorithm

Standard Starting Dose (Most Patients)

• 10 units once daily is the recommended fixed dose for most insulin-naive patients with type 2 diabetes 1, 2, 3
• Alternatively, use 0.2 units/kg body weight once daily if weight-based dosing is preferred 3
• The FDA label specifies "0.2 units/kg or up to 10 units once daily" as the approved starting dose 3

Severe Hyperglycemia (A1C ≥9% or Blood Glucose ≥300 mg/dL)

• Consider higher starting doses of 0.3-0.4 units/kg/day for patients with marked hyperglycemia 1
• For A1C ≥10-12% with symptomatic or catabolic features, start basal-bolus insulin immediately rather than basal insulin alone 1, 2

Dose Titration Protocol

Titration Schedule

• Increase by 2 units every 3 days if fasting glucose is 140-179 mg/dL 1
• Increase by 4 units every 3 days if fasting glucose is ≥180 mg/dL 1
• Target fasting glucose: 80-130 mg/dL 1
• If hypoglycemia occurs without clear cause, reduce dose by 10-20% immediately 1

Patient Self-Titration

• Equip patients with self-titration algorithms based on daily fasting glucose monitoring 1, 2
• Patient-managed titration achieves greater HbA1c reductions (-1.22% vs -1.08%) compared to clinic-managed titration 4

Concurrent Medications

Continue These Medications

• Metformin must be continued unless contraindicated, even when starting insulin 1, 2
• Possibly continue one additional non-insulin agent 1, 2
• SGLT2 inhibitors or thiazolidinediones may be continued to reduce total insulin requirements 2

Discontinue These Medications

• Sulfonylureas should be discontinued when advancing beyond basal-only insulin to prevent hypoglycemia 1
• DPP-4 inhibitors and GLP-1 receptor agonists are typically discontinued with complex insulin regimens 2

Critical Threshold: When to Stop Escalating Basal Insulin

When Lantus 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
• Episodes of hypoglycemia 1
• High glucose variability throughout the day 1

Adding Prandial Insulin

• Start with 4 units of rapid-acting insulin before the largest meal OR use 10% of the current basal dose 1
• Add prandial insulin if fasting glucose reaches target but HbA1c remains above goal after 3-6 months 1

Administration Guidelines

Injection Technique

• Administer subcutaneously once daily at the same time each day 3
• Inject into abdominal area, thigh, or deltoid 3
• Rotate injection sites within the same region to reduce lipodystrophy risk 3
• Never administer intravenously or via insulin pump 3
• Do not dilute or mix with any other insulin or solution 3

Monitoring Requirements

During Titration Phase

• Daily fasting blood glucose monitoring is essential 1
• Check HbA1c every 3 months during intensive titration 1
• Reassess every 3 days during active titration 1

Long-Term Monitoring

• Reassess every 3-6 months once stable 1
• Monitor for signs of overbasalization at every clinical visit 1

Common Pitfalls to Avoid

Clinical Errors

• Never delay insulin initiation in patients not achieving glycemic goals with oral medications—this prolongs hyperglycemia exposure and increases complication risk 1, 2
• Never discontinue metformin when starting insulin unless contraindicated—this leads to higher insulin requirements and more weight gain 1
• Never continue escalating basal insulin beyond 0.5-1.0 units/kg/day without addressing postprandial hyperglycemia—this causes overbasalization with increased hypoglycemia risk 1

Patient Education Gaps

• Never use insulin as a threat or describe it as a sign of personal failure 2
• Provide comprehensive education on injection technique, glucose monitoring, hypoglycemia recognition/treatment, and sick day management 1

Special Populations

High-Risk Patients (Elderly >65 years, Renal Failure, Poor Oral Intake)

• Use lower starting doses of 0.1-0.25 units/kg/day to prevent hypoglycemia 1
• Monitor glucose more frequently 1

Chronic Kidney Disease

• For CKD Stage 5, reduce total daily insulin dose by 50% for type 2 diabetes 1
• Titrate conservatively with eGFR <45 mL/min/1.73 m² 1

This dosing approach prioritizes safety while achieving glycemic targets, with the flexibility to intensify therapy based on individual response and glucose patterns.