NPO Dose of Lantus for a 65-Year-Old Male with Type 2 Diabetes
Continue the full 15 units of Lantus (insulin glargine) daily when NPO, as basal insulin provides essential background insulin coverage independent of nutritional intake. 1
Rationale for Continuing Full Basal Dose
Basal insulin like Lantus provides continuous background insulin coverage that is required 24 hours daily regardless of eating status, mimicking the body's baseline insulin secretion that occurs even during fasting states 1, 2
The 2017 Diabetes Care guidelines for hospitalized older adults explicitly state that when patients have reduced oral intake or become NPO, the basal insulin should be maintained while adding dextrose infusion (10% dextrose) to prevent hypoglycemia rather than reducing the basal dose 1
Lantus has a peakless 24-hour action profile, meaning it does not have significant peaks that would cause hypoglycemia during NPO periods when administered at appropriate doses 2, 3
Critical Management During NPO Status
Start 10% dextrose infusion (typically 75-100 mL/hour) when the patient becomes NPO to provide glucose substrate while maintaining basal insulin coverage 1
Monitor blood glucose every 4-6 hours during NPO status, with more frequent checks if any value falls below 100 mg/dL 1
Hold all prandial (mealtime) insulin completely during NPO periods, as these are specifically designed to cover carbohydrate intake 1
Dose Adjustment Considerations
If blood glucose drops below 70 mg/dL during NPO status despite dextrose infusion, reduce the Lantus dose by 10-20% (to 12-13.5 units) 1
For older adults (age 65) with any degree of renal impairment, frailty, or recurrent hypoglycemia, consider reducing to 80% of the usual dose (12 units) prophylactically when NPO 1
The 15-unit daily dose is already conservative for a 65-year-old, suggesting either good glycemic control or intentional conservative dosing, which supports maintaining the full dose during brief NPO periods 1
Common Pitfalls to Avoid
Never discontinue basal insulin entirely when NPO—this is the most common error and leads to diabetic ketoacidosis in type 1 diabetes and severe hyperglycemia in type 2 diabetes 1
Do not use sliding scale regular insulin alone during NPO periods without basal insulin coverage, as this approach results in poor glycemic control and higher complication rates 1
Failing to provide dextrose infusion when holding oral intake while continuing basal insulin is the second most common error, leading to hypoglycemia 1
For procedures or imaging requiring NPO status, coordinate timing so the patient receives Lantus at the usual time (whether morning or evening dosing) to maintain steady-state levels 1
Special Circumstances Requiring Dose Reduction
Reduce to 50-80% of usual dose (7.5-12 units) if the patient has: 1
- Acute kidney injury or chronic kidney disease stage 4-5
- Severe liver dysfunction
- History of severe hypoglycemia
- Prolonged NPO status expected (>48 hours)
- Sepsis or critical illness with unpredictable insulin sensitivity
For same-day procedures with brief NPO periods (<12 hours), continue the full 15 units without modification 1