At what glucose level should Lantus (insulin glargine) be held in a 16-year-old female with type 2 diabetes taking 44 units?

Holding Lantus in a 16-Year-Old Female with Type 2 Diabetes

Do not hold Lantus at any specific glucose threshold in this patient—basal insulin should be continued even during NPO status or acute illness to prevent metabolic decompensation, with dose reduction rather than complete discontinuation if hypoglycemia risk is high. 1

Critical Principle: Basal Insulin Should Not Be Routinely Held

• Basal insulin like Lantus provides continuous glucose control by suppressing hepatic glucose production between meals and overnight, and withholding it can lead to significant hyperglycemia and potential metabolic decompensation. 1
• The American Diabetes Association strongly discourages relying solely on sliding scale insulin without basal coverage in any clinical setting. 1
• For patients who are NPO or have poor oral intake, a basal plus correction insulin regimen is the preferred approach rather than withholding basal insulin entirely. 1

When to Reduce (Not Hold) Lantus Dose

Hypoglycemia Threshold for Dose Reduction

• If the patient experiences hypoglycemia (blood glucose <70 mg/dL), reduce the Lantus dose by 10-20% immediately rather than holding it completely. 2
• If more than two fasting glucose values per week are less than 80 mg/dL, decrease the basal insulin dose by 2 units to prevent recurrent hypoglycemia. 3

Special Clinical Situations Requiring Dose Reduction

• In perioperative settings when the patient is NPO, give 75-80% of the usual Lantus dose (approximately 33-35 units for this patient on 44 units) rather than holding it completely. 1
• For acute illness with poor oral intake, consider reducing to 0.1-0.25 units/kg/day rather than complete discontinuation. 3
• If the patient weighs approximately 50-60 kg, this 44-unit dose represents 0.7-0.9 units/kg/day, which is within typical ranges for type 2 diabetes but may need reduction during illness. 3

Monitoring Strategy When Continuing Lantus

• Monitor blood glucose every 4-6 hours when the patient is NPO or acutely ill, and supplement with correction-dose rapid-acting insulin as needed for hyperglycemia. 1
• Target fasting plasma glucose of 80-130 mg/dL for most adolescents with type 2 diabetes. 2
• For hospitalized patients, target glucose range of 140-180 mg/dL is recommended to balance efficacy with hypoglycemia risk. 2

Common Pitfall to Avoid

• The most dangerous error is completely holding basal insulin in response to a single low glucose reading or NPO status—this leads to rebound hyperglycemia and potential diabetic ketoacidosis, especially in adolescents who may have more labile glucose control. 1
• Abrupt discontinuation of insulin therapy can lead to poor glycemic control and metabolic complications. 1
• If supplemental insulin coverage is needed when Lantus is reduced, use short-acting insulin correction doses based on blood glucose monitoring rather than relying on sliding scale alone. 1

Specific Glucose Thresholds for Action

• Blood glucose <54 mg/dL (Level 2 hypoglycemia): Reduce Lantus dose by 10-20% and investigate the cause. 2
• Blood glucose 54-70 mg/dL (Level 1 hypoglycemia): Consider dose reduction if recurrent, but do not hold completely. 2
• Blood glucose >180 mg/dL while NPO: Continue Lantus and add correction insulin rather than increasing basal dose. 2, 1