Mixtard Starting Dose
For insulin-naive patients with type 2 diabetes, start Mixtard at 10 units per day or 0.1-0.2 units/kg/day, typically divided as two-thirds in the morning and one-third in the evening. 1
Initial Dosing Algorithm
For Insulin-Naive Type 2 Diabetes Patients
- Begin with 10 units per day OR 0.1-0.2 units/kg body weight per day 2, 1
- Divide the total daily dose: approximately 2/3 before breakfast and 1/3 before dinner 2, 1
- For a 70 kg patient, this translates to 7-14 units total daily, giving approximately 5-9 units in the morning and 2-5 units in the evening 3
For Patients Switching from NPH Insulin
- Calculate total daily dose as 80% of current NPH insulin dose 1
- This 20% reduction prevents hypoglycemia during the transition 1
- Split the reduced dose using the same 2/3 morning, 1/3 evening ratio 2
For Type 1 Diabetes Patients
- Start with 0.5 units/kg/day as total daily dose 1
- Mixtard provides both basal and prandial coverage in a single injection, though this is less commonly used in type 1 diabetes compared to basal-bolus regimens 2
Titration Strategy
- Increase dose by 2 units every 3 days if fasting glucose is 140-179 mg/dL 2
- Increase dose by 4 units every 3 days if fasting glucose is ≥180 mg/dL 2
- Target fasting plasma glucose of 80-130 mg/dL (4.4-7.2 mmol/L) 2, 1
- If hypoglycemia occurs without clear cause, reduce the dose by 10-20% immediately 2
Optimal Morning-to-Evening Ratio
Research suggests that starting with a higher morning dose (55:45 to 60:40 ratio) may be more appropriate than an equal split, as patients initially started on 50:50 ratios typically require upward adjustment of their morning dose over time 4. The American Diabetes Association guidelines support individualizing the split based on glucose patterns, with typical ratios of 2/3 morning and 1/3 evening 2.
Special Populations Requiring Dose Adjustment
- Elderly patients or those with renal impairment: Start at the lower end (0.1 units/kg/day) to minimize hypoglycemia risk 3
- Patients with severe hyperglycemia (A1C ≥10%, glucose ≥300 mg/dL): Consider higher starting doses of 0.3-0.4 units/kg/day or a basal-bolus regimen instead 2, 5
Critical Pitfalls to Avoid
- Never convert from NPH to Mixtard on a 1:1 basis—always use 80% of the NPH dose to prevent hypoglycemia 1
- Do not delay dose titration—adjust every 3 days based on fasting glucose readings rather than waiting weeks between adjustments 2
- Avoid using premixed insulins like Mixtard in hospitalized patients due to unacceptably high rates of hypoglycemia 5
- Do not rely on sliding scale insulin alone—scheduled insulin regimens with both basal and prandial components are superior 5
Monitoring Requirements
- Daily fasting blood glucose monitoring is essential during titration 2, 1
- Monitor both fasting and postprandial glucose levels to assess regimen effectiveness 1
- Reassess insulin dose adequacy at every clinical visit 2
- Continue metformin unless contraindicated when initiating or intensifying insulin therapy 2, 5