From the Guidelines
When the sliding scale of short-acting insulin exceeds the maximum recommended dose with each meal, the long-acting insulin dose should be adjusted to optimize basal glucose control, and I recommend gradually increasing the long-acting insulin dose by 10-20% (for example, from 0.2 units/kg/day to 0.22-0.24 units/kg/day) while closely monitoring blood glucose levels, as suggested by the most recent guidelines 1. This approach is based on the understanding that long-acting insulin provides continuous coverage for hepatic glucose production, and inadequate basal insulin necessitates higher correction doses of short-acting insulin, potentially leading to hypoglycemia and glucose variability. Key considerations in adjusting long-acting insulin include:
- Monitoring pre-meal and bedtime glucose levels for 2-3 days before making further adjustments
- Being aware of the potential for overbasalization, which can mask insufficient mealtime insulin and lead to hypoglycemia, high glucose variability, or elevated bedtime-to-morning glucose differentials 1
- Adjusting the sliding scale parameters if hypoglycemia occurs after increasing the long-acting dose
- Considering the use of adjunctive therapies, such as GLP-1 RAs, if A1C remains above goal despite optimized insulin therapy 1 The goal of these adjustments is to achieve optimal glucose control while minimizing the risk of hypoglycemia, as supported by recent studies on pharmacologic approaches to glycemic treatment 1.
From the FDA Drug Label
The FDA drug label does not answer the question.
From the Research
Adjusting Long-Acting Insulin Doses
When using long-acting (basal) insulin at a dose of 0.2 units/kilogram/day and the sliding scale of short-acting (bolus) insulin exceeds the maximum recommended dose with each meal, the following points should be considered:
- The effectiveness of sliding scale insulin regimens has been questioned, with studies suggesting that they are ineffective and potentially dangerous 2, 3.
- Alternative insulin regimens, such as basal-bolus insulin therapy, have been shown to be more effective in achieving glycemic control 2, 4.
- The adjustment of basal insulin doses can be guided by equations that describe the relationship between baseline and follow-up doses of basal insulin, as seen in the study by 5.
- However, these equations may not be directly applicable to the scenario described, and individualized adjustment of insulin doses may be necessary.
Considerations for Insulin Therapy
When adjusting insulin doses, the following considerations should be taken into account:
- The target blood glucose concentrations, which may vary depending on the patient's condition and the clinical setting 2, 4.
- The risk of hypoglycemia, which is a primary limiting factor for achieving optimal glycemic control with insulin therapy 2, 4.
- The use of computer decision support systems, which can help reduce the risk of insulin infusion rate calculation errors and standardize insulin therapy 2.
- The importance of individualizing insulin regimens and avoiding wide fluctuations in glucose levels 6.
Alternative Insulin Regimens
Alternative insulin regimens, such as basal-bolus insulin therapy, may be more effective in achieving glycemic control than sliding scale insulin regimens:
- Basal-bolus insulin therapy involves administering a single daily dose of long-acting insulin, bolus injections of rapid-acting insulin before meals, and correction bolus injections as needed 2, 4.
- This approach has been shown to result in better glycemic control and lower risk of hypoglycemia than sliding scale insulin regimens 3, 4.