When should 70/30 (pre-mixed insulin) be held?

When to Hold 70/30 Premixed Insulin

Premixed 70/30 insulin should be held in hospitalized patients and is not recommended for inpatient use due to unacceptably high rates of hypoglycemia. 1

Primary Recommendation for Hospitalized Patients

Do not use 70/30 premixed insulin in the hospital setting. Multiple major diabetes guidelines explicitly discourage its use:

• The Lancet Diabetes and Endocrinology states that premixed insulin therapy (human insulin 70/30) has been associated with an unacceptably high rate of iatrogenic hypoglycemia and is not recommended in the hospital 1
• The American Diabetes Association Standards of Care consistently report that 70/30 NPH/regular insulin showed comparable glycemic control to basal-bolus therapy but with significantly increased hypoglycemia, making premixed insulin regimens not routinely recommended for in-hospital use 1
• Research confirms that premixed insulin carries a 3-fold higher risk of hypoglycemic episodes compared to other regimens 2

Specific Clinical Situations Requiring Discontinuation

Upon Hospital Admission

• Hold 70/30 insulin immediately upon admission and transition to basal-bolus or basal-plus regimens for better safety and flexibility 1
• Convert using 70% of the total daily dose as basal insulin only, administered in the morning 1

Patients with Poor Oral Intake or NPO Status

• Hold 70/30 insulin when patients are not eating or have poor oral intake, as the fixed prandial component (30% rapid-acting) creates unacceptable hypoglycemia risk without carbohydrate intake 1
• Switch to basal insulin alone or basal-plus correction regimen 1

Patients at High Risk for Hypoglycemia

Hold or avoid 70/30 insulin in:

• Older adults (>65 years) 1
• Patients with renal failure or impaired renal function 1
• Patients with unpredictable eating patterns 3
• Those with history of severe hypoglycemia 3

Perioperative and Procedural Settings

• Hold 70/30 insulin for patients undergoing surgery or procedures and use basal-plus approach instead to avoid hypoglycemia during fasting periods 1

Preferred Alternative Regimens

When discontinuing 70/30 insulin, transition to:

• Basal-bolus regimen (basal insulin once or twice daily plus rapid-acting insulin before meals) for patients with good oral intake 1
• Basal-plus regimen (basal insulin with correction doses only) for patients with mild hyperglycemia, decreased oral intake, or undergoing surgery 1
• Starting dose: 0.3-0.5 U/kg total daily insulin, with half as basal and half as prandial (divided three times daily) 1
• Lower doses (0.1-0.25 U/kg) for high-risk patients 1

Critical Safety Considerations

• The fixed 70/30 ratio provides no flexibility to adjust basal versus prandial components independently, creating inherent safety problems in the hospital where oral intake is unpredictable 3
• Sliding scale insulin alone, while discouraged as monotherapy, is actually safer than 70/30 premixed insulin in hospitalized patients 4
• Any blood glucose <70 mg/dL (3.9 mmol/L) should trigger immediate regimen review and adjustment 1

Exception: Outpatient/Ambulatory Setting Only

70/30 insulin may be continued in stable outpatient settings with:

• Predictable meal patterns and timing 5, 3
• Administration 30 minutes before breakfast and dinner 5, 3
• Target fasting glucose 90-150 mg/dL 5, 3
• Regular monitoring and dose adjustments every 2 weeks 5, 3

However, even in outpatients, consider transitioning to basal-bolus regimens for better flexibility and lower hypoglycemia risk 1, 3.