From the Guidelines
Converting basal-bolus insulin to Mixtard insulin should be done by adding 4 units of short/rapid-acting insulin to each injection or 10% of reduced NPH dose, as recommended in the 2023 standards of care in diabetes 1. To initiate this conversion, calculate the total daily insulin dose by adding all basal and bolus insulin amounts used in 24 hours.
- Divide this total into two doses of Mixtard, typically giving two-thirds in the morning and one-third in the evening, administered 30 minutes before meals.
- For example, if a patient uses 20 units of basal insulin and 30 units of bolus insulin daily (total 50 units), they might take 34 units of Mixtard before breakfast and 16 units before dinner. This conversion should always be supervised by a healthcare provider as Mixtard contains fixed ratios of rapid/short-acting and intermediate-acting insulin, which provides less flexibility than basal-bolus regimens.
- Blood glucose should be monitored frequently after switching, especially before meals and at bedtime, with dose adjustments made gradually. The conversion is necessary because Mixtard combines both insulin types in one injection, which may be easier for some patients but offers less precise control than separate basal and bolus dosing, as outlined in the 2023 pharmacologic approaches to glycemic treatment standards of care in diabetes 1.
From the Research
Converting Basal Bolus Insulin to Mixtard Insulin
To convert basal bolus insulin to Mixtard insulin, several factors need to be considered, including the type of insulin, dosage, and patient response.
- The study 2 compared the efficacy of biphasic insulin aspart (BIAsp 30) with other treatment regimens, including basal insulin and conventional insulins, in patients with type 2 diabetes.
- Another study 3 compared the efficacy and safety of BIAsp 30 with insulin glargine in patients with type 2 diabetes who were not maintaining glycemic control on basal insulin and oral antidiabetic drugs.
- The pharmacokinetic and pharmacodynamic properties of BIAsp 30 and insulin glargine were compared in a study 4, which found that BIAsp 30 had a more rapid onset of action and a distinct peak in glucose infusion rates and plasma insulin concentrations.
- A randomized cross-over trial 5 compared the efficacy of insulin glargine and aspart with NPH insulin and aspart in a basal bolus regimen in type 1 diabetes, finding that glargine and aspart resulted in lower HbA1c levels and improved patient satisfaction.
Key Considerations
- When converting basal bolus insulin to Mixtard insulin, the dosage and administration schedule may need to be adjusted to achieve optimal glycemic control.
- The type of insulin and patient response should be taken into account, as different insulins have different pharmacokinetic and pharmacodynamic profiles.
- Studies have shown that BIAsp 30 can be an effective alternative to basal insulin and conventional insulins in patients with type 2 diabetes, but the optimal dosage and administration schedule may vary depending on individual patient needs.
- More research is needed to fully understand the effects of converting basal bolus insulin to Mixtard insulin, particularly in patients with type 1 diabetes.
Dosage and Administration
- The dosage of Mixtard insulin will depend on the individual patient's insulin needs and response to treatment.
- The administration schedule may need to be adjusted to achieve optimal glycemic control, with some studies suggesting that twice-daily administration of BIAsp 30 may be more effective than once-daily administration of insulin glargine.
- Patients should be closely monitored for hypoglycemia and other adverse effects when converting to Mixtard insulin, and the dosage and administration schedule should be adjusted as needed to minimize these risks.