From the Guidelines
To calculate insulin starting doses for bolus and basal therapy, begin with a total daily insulin dose (TDD) of 0.3-0.5 units/kg of body weight for most adults with type 1 diabetes, or 0.2-0.3 units/kg for type 2 diabetes, as recommended by the most recent and highest quality study 1.
Calculating Insulin Doses
The total daily dose can be divided into approximately 50% basal insulin (long-acting) and 50% bolus insulin (rapid-acting).
- For example, a 70 kg person with type 1 diabetes might start with 28 units total daily (0.4 units/kg), with 14 units as basal insulin once daily (such as glargine or detemir) and the remaining 14 units divided among meals as bolus insulin (such as lispro, aspart, or glulisine).
- For bolus insulin, initially distribute the dose proportionally based on carbohydrate content of meals, typically 4-5 units before each major meal.
- Alternatively, use an insulin-to-carbohydrate ratio starting at 1 unit per 10-15g of carbohydrates.
Adjusting Insulin Doses
Correction doses for high blood glucose can start at 1 unit for every 50 mg/dL above target.
- These doses require frequent blood glucose monitoring and adjustment based on patterns.
- Lower initial doses are appropriate for elderly patients, those with renal or hepatic impairment, or those at higher risk of hypoglycemia.
Physiological Basis
The physiological basis for this approach mimics normal pancreatic function, with basal insulin controlling glucose between meals and overnight, while bolus insulin manages post-meal glucose excursions, as supported by studies 2, 3, 4.
- The goal is to achieve optimal glycemic control while minimizing the risk of hypoglycemia and other complications.
- Regular monitoring and adjustments are crucial to ensure the best possible outcomes in terms of morbidity, mortality, and quality of life.
From the FDA Drug Label
The initial programming of the external insulin infusion pump should be based on the total daily insulin dose of the previous regimen Although there is significant variability among patients, approximately 50% of the total dose is usually given as meal-related boluses of HUMALOG and the remainder is given as a basal infusion.
The method for calculating initial insulin doses for bolus (fast-acting insulin) + basal (long-acting insulin) therapy is to base the initial programming of the external insulin infusion pump on the total daily insulin dose of the previous regimen. Approximately 50% of the total dose is usually given as meal-related boluses and the remainder as a basal infusion 5.
From the Research
Calculating Initial Insulin Doses
The provided studies do not directly address the method for calculating initial insulin doses for bolus (intraperitoneal/intramuscular injection of fast-acting insulin) + basal (long-acting insulin) therapy.
Key Findings from Relevant Studies
- The studies primarily focus on comparing the efficacy and safety of different insulin regimens, such as insulin detemir and NPH insulin, in patients with type 1 and type 2 diabetes 6, 7, 8, 9.
- They discuss the benefits of using insulin detemir, including improved glycemic control, reduced risk of hypoglycemia, and less weight gain 6, 7, 8, 9.
- One study reviews the role of basal insulin and glucagon-like peptide-1 agonists in the therapeutic management of type 2 diabetes, but does not provide information on calculating initial insulin doses 10.
Limitations
- The studies do not provide a clear method for calculating initial insulin doses for bolus and basal therapy.
- The information provided is focused on the comparison of different insulin regimens and their effects on glycemic control, hypoglycemia, and weight gain.
Available Information
- Some studies mention that insulin detemir and NPH insulin were administered once or twice daily, but do not provide details on how the initial doses were calculated 6, 7, 8, 9.
- The studies suggest that insulin detemir is a valuable option for basal insulin therapy, but do not provide guidance on calculating initial doses 9.