What is the recommended dose reduction for a diabetic adult patient experiencing hypoglycemia every morning while taking 27 units of Lantus (insulin glargine) nightly?

Reduce Lantus by 10-20% Immediately

For a patient experiencing morning hypoglycemia on 27 units of Lantus nightly, reduce the dose by 3-5 units (10-20% reduction) immediately. 1

Immediate Dose Adjustment

• For recurrent nocturnal hypoglycemia, use a 20% reduction (approximately 5 units, bringing the dose to 22 units), while for mild, isolated hypoglycemia, a 10% reduction (approximately 3 units, bringing the dose to 24 units) may be sufficient 1
• The American Diabetes Association recommends that if any episode of severe hypoglycemia occurs, the dose should be reduced by 10-20% 2
• Make the dose adjustment immediately—do not wait to see if the hypoglycemia recurs 1

Monitoring After Dose Reduction

• Check fasting blood glucose daily for at least one week after the dose reduction 1
• For nocturnal hypoglycemia specifically, check blood glucose at bedtime, 3:00 AM, and upon waking for several days to confirm resolution 1
• Target fasting glucose range of 80-130 mg/dL 1

Subsequent Titration Strategy

• If more than 50% of fasting glucose values remain above target after one week of the reduced dose, increase by 2 units 1
• If two or more fasting glucose values per week fall below 80 mg/dL, decrease by an additional 2 units 1
• Make adjustments every 3 days during active titration 1

Consider Timing Change if Hypoglycemia Persists

• Consider changing Lantus administration from evening to morning to reduce nocturnal hypoglycemia risk while maintaining 24-hour coverage 1, 3
• Morning administration of insulin glargine has been shown to have equivalent incidence of nocturnal hypoglycemia compared to bedtime dosing, with 13.0% vs 14.9% of patients experiencing nocturnal hypoglycemia 3
• The metabolic profile differs between morning and evening dosing: NPH insulin has greater effect on glucose metabolism at night, while insulin glargine is more effective in the morning, reducing endogenous glucose production by 5.7 micromol/kg/min 4

Evaluate for Overbasalization

• Look for clinical signals of overbasalization, including high bedtime-to-morning glucose differential (≥50 mg/dL drop overnight), which suggests excessive basal insulin 1
• If the patient's basal insulin dose exceeds 0.5 units/kg/day (approximately 35 units for a 70 kg patient), this signals potential overbasalization and the need to add prandial insulin rather than continuing basal insulin alone 2, 1

Critical Pitfall to Avoid

• Continuing the same dose without adjustment after a hypoglycemic event significantly increases risk of recurrent severe hypoglycemia 1
• The danger of not adjusting is demonstrated by data showing 75% of hospitalized patients who experienced hypoglycemia had no basal insulin dose adjustment before the next administration 2

Alternative Insulin Considerations

• Consider switching to newer ultra-long-acting basal analogs (insulin degludec or U-300 glargine) if hypoglycemia persists despite dose reduction, as these have lower nocturnal hypoglycemia rates than U-100 glargine 1
• Meta-analysis data shows insulin glargine reduces nocturnal hypoglycemia by 26% compared to NPH insulin, with severe nocturnal hypoglycemia reduced by 59% 5
• In observational studies, switching to insulin glargine reduced severe nocturnal hypoglycemia from 3.84 episodes/patient/year to 0.0096 episodes/patient/year in type 1 diabetes 6

Follow-Up Timing

• Schedule reassessment within 1-2 weeks after any dose reduction for hypoglycemia to review glucose logs, identify patterns, and make further adjustments as needed 1