How to adjust Lantus (insulin glargine) for a type 2 diabetes patient who will be NPO (nothing by mouth) at midnight?

Managing Lantus During NPO Status for Type 2 Diabetes

Direct Recommendation

Continue the full 60 units of Lantus at the usual administration time when the patient becomes NPO at midnight. 1

Rationale for Continuing Full Basal Insulin Dose

Basal insulin like Lantus controls hepatic glucose production continuously throughout the day and night, independent of meal intake. 1 The long-acting profile of insulin glargine provides steady background insulin levels over approximately 24 hours with no peak action time, making it fundamentally different from prandial insulin that covers meals. 2, 3

For this specific patient (95 kg, BMI 30, on 60 units Lantus = 0.63 units/kg/day), the current dose is already in the therapeutic range for type 2 diabetes and should be maintained during NPO status. 1

Critical Monitoring Protocol During NPO Period

• Check blood glucose every 4-6 hours throughout the NPO period to detect hypoglycemia early. 1

• Have rapid-acting glucose sources immediately available (glucose tablets or IV dextrose 50%) at the bedside. 1

• If blood glucose falls below 70 mg/dL, administer 15-20g of glucose (if oral intake permitted) or IV dextrose if strictly NPO. 1

When to Consider Dose Reduction (Special Circumstances Only)

Reduce the Lantus dose by 20% (to 48 units) ONLY if:

• The patient has excellent glycemic control with HbA1c <7% AND will be NPO for more than 24 hours. 1

• The patient is elderly or has renal impairment, which increases hypoglycemia risk. 1

For this 47-year-old patient with no mention of renal disease or excellent control, maintain the full 60 units. 1

If Hypoglycemia Occurs During NPO Period

• Treat the hypoglycemia immediately with glucose. 1

• Reduce the next day's Lantus dose by 10-20% (to 48-54 units). 1

• Do not skip or reduce the current dose retroactively. 1

Common Pitfalls to Avoid

Never completely stop basal insulin during NPO status - this leads to significant hyperglycemia from unrestrained hepatic glucose production, even without food intake. 1

Do not reduce the dose preemptively without specific risk factors - most patients tolerate their usual basal insulin dose during short-term NPO periods without hypoglycemia. 1

Failing to increase monitoring frequency is dangerous and can result in undetected hypoglycemia. 1

Resuming Normal Regimen

• Continue the regular 60-unit Lantus dosing schedule once oral intake resumes. 1

• If any dose adjustments were made during the NPO period, gradually titrate back to the usual 60 units over 2-3 days. 1

• Monitor blood glucose closely during the transition back to normal eating patterns. 1