In an inpatient who is fasting with a blood glucose of 201 mg/dL and is currently receiving insulin glargine (Lantus) 10 units nightly, what recommendations should be made for the Lantus dosing?

Increase Lantus to 0.5 units/kg/day and add scheduled rapid-acting insulin before meals

For an inpatient who is fasting with a blood glucose of 201 mg/dL on Lantus 10 units nightly, you should calculate a new total daily insulin dose based on 0.5 units/kg/day (since the glucose is 201-400 mg/dL range), split this 50/50 between basal and nutritional insulin, and add correction insulin. Since the patient is currently fasting, continue the increased basal insulin dose and provide correction doses of rapid-acting insulin every 4-6 hours until eating resumes 1.

Immediate Action Plan

Step 1: Calculate Weight-Based Dosing

The Endocrine Society guideline is explicit: for hospitalized patients with blood glucose 201-400 mg/dL (11.2-22.2 mmol/L), use 0.5 units/kg/day as the total daily insulin dose 1. This is higher than the 0.4 units/kg used for glucose 140-200 mg/dL, reflecting the need for more aggressive control at this glucose level.

• If patient weighs 70 kg: Total daily dose = 0.5 × 70 = 35 units
• Basal insulin (50% of total) = 17.5 units (round to 18 units)
• Nutritional insulin (50% of total) = 17.5 units

Important caveat: If the patient is ≥70 years old OR has GFR <60 mL/min, use the lower dose of 0.2-0.3 units/kg/day instead to reduce hypoglycemia risk 1.

Step 2: Since Patient is NPO (Fasting)

• Continue basal insulin at the calculated dose (e.g., 18 units if 70 kg patient)
• Hold nutritional/prandial insulin (since not eating)
• Add correction insulin: Use rapid-acting insulin analog every 4 hours OR regular insulin every 6 hours 1

Step 3: Correction Insulin Scale

Use the "insulin-sensitive" column for elderly patients, those not eating, or those with renal impairment. Otherwise use the "usual" column 1:

Usual Column (for most patients):

• BG 141-180: 4 units
• BG 181-220: 6 units
• BG 221-260: 8 units ← Current patient at 201 mg/dL would get 6 units

Insulin-sensitive column (elderly, renal impairment, NPO):

• BG 141-180: 2 units
• BG 181-220: 4 units
• BG 221-260: 6 units

Critical Pitfalls to Avoid

Do NOT continue sliding scale insulin (SSI) alone - this outdated practice increases the risk of hyperglycemia 3-fold and is strongly discouraged 1. The current regimen of "Lantus 10 units" without scheduled nutritional insulin is inadequate.

Do NOT use the home dose without adjustment - Studies show that 30% of patients on basal-bolus therapy experience hypoglycemia when continued on their home insulin dose without reassessment 1. The current 10 units is likely insufficient based on the fasting glucose of 201 mg/dL.

Monitor for hypoglycemia between midnight and 6 AM - This is when 78% of hypoglycemic episodes occur in hospitalized patients on basal insulin 2. If fasting glucose drops below 100 mg/dL, this predicts next-day hypoglycemia and warrants dose reduction 2.

When Patient Resumes Eating

Once oral intake resumes, transition to full basal-bolus regimen:

• Continue basal insulin (e.g., 18 units daily)
• Add prandial insulin: Divide the nutritional component equally before each meal (e.g., 6 units before each of 3 meals if total nutritional dose is 18 units) 1
• Continue correction insulin with meals using the appropriate column

Titration Strategy

Adjust basal insulin based on fasting glucose every 2-3 days 3:

• If fasting glucose remains >150 mg/dL: Increase by 2 units
• If fasting glucose <80 mg/dL on >2 occasions: Decrease by 2 units (or 10-20% of dose) 3

The 2025 ADA Standards recommend increasing by 2 units every 3 days to reach fasting plasma glucose goal without hypoglycemia 3.

Special Considerations

Renal impairment: Kidney failure increases hypoglycemia risk due to decreased insulin clearance 2. However, one study found patients with renal failure may paradoxically require higher basal insulin doses to achieve target glucose 4. Monitor closely and adjust based on response.

Elderly patients: Use lower starting doses (0.2-0.3 units/kg) and the insulin-sensitive correction scale 1.

HbA1c correlation: Higher admission HbA1c (≥8.0%) correlates with higher basal insulin requirements 4. If available, use this to guide initial dosing expectations.

The evidence strongly supports moving away from the current inadequate regimen to a structured basal-bolus approach with appropriate weight-based dosing for this level of hyperglycemia.