Hold Parameters for Lantus (Insulin Glargine)
Lantus should generally NOT have routine hold parameters based on blood glucose levels alone, as it is a basal insulin designed to provide continuous 24-hour coverage regardless of meal intake or current glucose values. 1
Why Basal Insulin Differs from Prandial Insulin
- Basal insulin (Lantus) addresses fasting and between-meal glucose levels by restraining hepatic glucose production continuously throughout the day and night, not acute hyperglycemic excursions 2
- Unlike prandial or correctional insulin that responds to meals or elevated glucose, Lantus provides a relatively constant basal level of circulating insulin with no pronounced peak 3, 4
- Holding Lantus based on a single low or normal glucose reading will result in loss of basal coverage for the entire 24-hour period, leading to hyperglycemia 1
When Dose Reduction (Not Holding) Is Appropriate
Instead of holding Lantus entirely, reduce the dose by 10-20% if:
- More than 2 fasting glucose values per week are less than 80 mg/dL (4.4 mmol/L) 2
- Any episode of severe hypoglycemia occurs (blood glucose <54 mg/dL or <3.0 mmol/L) 5, 2
- Recurrent nocturnal hypoglycemia is documented 2
Special Clinical Situations Requiring Dose Adjustment
Reduce the total daily insulin dose by 20% (not hold completely) when:
- Patients are hospitalized and were on high-dose home insulin (≥0.6 units/kg/day) to prevent hypoglycemia 2
- Patients have acute illness with poor oral intake - consider lower doses (0.1-0.25 units/kg/day) for high-risk patients such as elderly (>65 years) or those with renal failure 2
- Patients are NPO (nothing by mouth) for procedures - reduce basal insulin dose but do not eliminate it entirely, as basal insulin requirements persist even without food intake 2
Critical Pitfall to Avoid
The most dangerous error is implementing "sliding scale only" or holding all insulin when a patient is NPO or has low-normal glucose values. This approach:
- Eliminates basal coverage needed to suppress hepatic glucose production 2
- Results in rebound hyperglycemia within hours 2
- Was associated with 75% of hospitalized patients experiencing hypoglycemia without appropriate dose adjustment before the next administration 2
Proper Monitoring During Dose Adjustments
- Assess adequacy of insulin dose at every clinical visit, looking for signs of overbasalization (basal dose >0.5 units/kg/day, bedtime-to-morning glucose differential ≥50 mg/dL, hypoglycemia, high glucose variability) 2
- Daily fasting blood glucose monitoring is essential during titration phases 2
- Increase frequency of blood glucose monitoring during any changes to insulin regimen 1