How to manage hypoglycemia in a patient on Lantus (insulin glargine) with a fasting blood glucose of 85 mg/dL and currently taking 40 units?

Management of Low-Normal Fasting Blood Glucose on Lantus 40 Units

Reduce your Lantus dose by 4 units (to 36 units) immediately, as a fasting blood glucose of 85 mg/dL on 40 units of basal insulin places you at significant risk for hypoglycemia. 1, 2

Understanding Your Current Situation

Your fasting blood glucose of 85 mg/dL falls within the target range of 80-130 mg/dL, but it is dangerously close to the hypoglycemia threshold of 70 mg/dL 1. This narrow safety margin means even minor variations in food intake, physical activity, or insulin absorption could push you into hypoglycemia 1.

• A blood glucose level approaching the lower end of the target range indicates potential risk for hypoglycemia if the full insulin dose continues 2
• Level 1 hypoglycemia is defined as glucose <70 mg/dL (<3.9 mmol/L), and you are only 15 mg/dL away from this threshold 1, 2

Immediate Dose Adjustment Protocol

Reduce your Lantus by 10% (approximately 4 units, from 40 to 36 units) tonight. 3, 2

• The American Diabetes Association recommends a 10-20% dose reduction when hypoglycemia risk is increased 2
• If more than two fasting blood glucose values per week are less than 80 mg/dL, decrease the dose by 2 units 3
• For patients at risk of hypoglycemia, particularly those on higher insulin doses, a 20% reduction may be appropriate 2

Monitoring Requirements After Dose Reduction

Check your fasting blood glucose daily for the next 3-5 days to determine if further adjustments are needed 2:

• Monitor at least 4 times daily during this adjustment period: fasting, before lunch, before dinner, and at bedtime 2
• Pay special attention to fasting morning glucose levels and any signs of hypoglycemia 2
• Keep glucose tablets (15-20g) readily available for immediate treatment if hypoglycemia occurs 1, 2

Titration Strategy Going Forward

Once your fasting glucose stabilizes on the reduced dose, use this algorithm for future adjustments 3:

• If fasting glucose is 140-179 mg/dL: Increase by 2 units every 3 days 3
• If fasting glucose is ≥180 mg/dL: Increase by 4 units every 3 days 3
• If fasting glucose is <80 mg/dL more than twice weekly: Decrease by 2 units 3
• Target fasting glucose: 80-130 mg/dL 1

Hypoglycemia Recognition and Treatment

Be prepared to recognize and treat hypoglycemia immediately 1, 2:

• Symptoms include: shakiness, irritability, confusion, rapid heartbeat, sweating, and hunger 2
• Treatment: Consume 15-20g of fast-acting carbohydrate (glucose tablets preferred) 1
• Recheck glucose after 15 minutes; if still <70 mg/dL, repeat treatment 1
• After recovery: Eat a meal or snack to prevent recurrence 1

Critical Threshold Considerations

Your current dose of 40 units may be approaching a critical threshold where additional considerations are needed 3:

• When basal insulin exceeds 0.5 units/kg/day (approximately 35-40 units for a 70-80 kg person), adding prandial insulin becomes more appropriate than continuing to escalate basal insulin alone 3
• If your A1C remains elevated despite controlled fasting glucose, you may need mealtime insulin coverage rather than more basal insulin 3

Common Pitfalls to Avoid

• Do not ignore low-normal fasting glucose values thinking they represent "good control"—they represent excessive basal insulin and hypoglycemia risk 2
• Do not delay dose reduction when fasting glucose consistently approaches 80 mg/dL 2
• Do not use protein-rich foods to treat hypoglycemia; use 15-20g of pure glucose or fast-acting carbohydrates instead 1
• Do not skip meals or delay eating after taking your Lantus dose, as this increases hypoglycemia risk 1

When to Seek Immediate Medical Attention

Contact your healthcare provider immediately if 1, 2:

• You experience severe hypoglycemia requiring assistance from another person
• You have recurrent episodes of blood glucose <70 mg/dL despite dose reduction
• You develop hypoglycemia unawareness (inability to recognize symptoms)
• You experience confusion, seizures, or loss of consciousness