What is the recommended starting dose of Lantus (insulin glargine) for a 63-year-old female patient with Type 2 Diabetes Mellitus (T2DM) and a weight of 236 pounds?

Recommended Starting Dose of Lantus for a 63-Year-Old Female with T2DM Weighing 236 lbs

For this 63-year-old female patient with Type 2 Diabetes weighing 236 lbs (107 kg), start Lantus at 10 units subcutaneously once daily, administered at the same time each day. 1

Initial Dosing Strategy

The FDA-approved prescribing information for Lantus specifies that the recommended starting dosage in patients with Type 2 Diabetes who are not currently treated with insulin is 0.2 units/kg or up to 10 units once daily 1. Given this patient's weight:

• Weight-based calculation: 0.2 units/kg × 107 kg = 21.4 units
• Conservative starting dose: 10 units once daily

The 10-unit starting dose is the appropriate choice because it represents the safer, more conservative approach recommended by the FDA label, particularly for insulin-naive patients 1. While the weight-based calculation suggests a higher dose, starting lower minimizes hypoglycemia risk during the initial titration phase.

Titration Protocol

After initiating at 10 units daily, titrate the dose systematically to achieve target fasting blood glucose (FBG) of ≤5.5 mmol/L (≤100 mg/dL) 2:

• Increase the dose by 2 units every 3 days if FBG remains above target and no hypoglycemia occurs 2
• Alternatively, use a structured weekly titration: increase by 2-8 units based on the mean FBG over the previous 3 days 2:
  • If FBG ≥5.6-<6.7 mmol/L (≥100-<120 mg/dL): increase by 0-2 units
  • If FBG ≥6.7-<7.8 mmol/L (≥120-<140 mg/dL): increase by 2 units
  • If FBG ≥7.8-<10.0 mmol/L (≥140-<180 mg/dL): increase by 4 units
  • If FBG ≥10 mmol/L (≥180 mg/dL): increase by 6-8 units

Patient-managed titration (increasing by 2 units every 3 days) achieves greater HbA1c reductions (-1.22% vs -1.08%) compared to clinic-managed titration, though with slightly higher hypoglycemia rates (33.3% vs 29.8%) 2. The choice depends on the patient's capability for self-management and hypoglycemia risk tolerance.

Administration Details

• Inject subcutaneously once daily at the same time each day (morning or evening, patient's choice) 1
• Rotate injection sites within the abdomen, thigh, or deltoid to prevent lipodystrophy 1
• Do not mix or dilute Lantus with any other insulin or solution 1
• Visually inspect for particulate matter; use only if clear and colorless 1

Monitoring Requirements

• Increase frequency of blood glucose monitoring during dose titration 1
• Monitor fasting blood glucose daily during the titration phase 2
• Check HbA1c every 3 months to assess overall glycemic control 3
• Watch for signs and symptoms of hypoglycemia, particularly nocturnal hypoglycemia 4

Concomitant Oral Medications

Continue metformin and other oral antidiabetic agents unless contraindicated 1, 5. The addition of basal insulin to oral agents is more effective than intensifying oral therapy alone, achieving HbA1c reductions of 1.55% when added to existing oral agents 5.

If the patient is taking sulfonylureas, consider reducing the sulfonylurea dose by 50% when initiating insulin to minimize hypoglycemia risk 3.

Special Considerations for Older Adults

For this 63-year-old patient, consider the following based on the American Diabetes Association's 2024 guidelines for older adults 3:

• Target HbA1c of <7.0-7.5% is appropriate if she is healthy with few comorbidities 3
• Simplify the regimen if cognitive or functional impairment develops: switch basal insulin timing from bedtime to morning to reduce nocturnal hypoglycemia risk 3
• Fasting glucose target of 90-150 mg/dL may be more appropriate than the stricter <100 mg/dL target if she has multiple comorbidities 3

Expected Outcomes

With proper titration, this patient can expect:

• HbA1c reduction of approximately 1.0-1.5% from baseline 2, 5
• Fasting blood glucose reduction of 2.7-3.0 mmol/L (49-54 mg/dL) 6
• Weight gain of approximately 1-2 kg over 24 weeks 6, 5
• Low incidence of severe hypoglycemia (<1%) with proper titration 6
• Significantly lower nocturnal hypoglycemia compared to NPH insulin 4

Common Pitfalls to Avoid

• Do not administer intravenously or via insulin pump 1
• Do not inject into areas of lipodystrophy, as this causes erratic absorption and hyperglycemia 1
• Do not undertitrate: Many patients remain on suboptimal doses; aggressive titration to FBG <100 mg/dL is necessary to achieve HbA1c <7% 2
• Do not discontinue oral agents prematurely: Metformin should be continued unless contraindicated 5