What is the recommended insulin regimen for a patient with diabetes requiring insulin therapy, with specific guidelines for blood sugar management and sliding scale dosing?

Insulin Regimen for Blood Sugar Management with Fixed Dose and Sliding Scale

For a patient requiring insulin therapy with blood sugar management guidelines, the recommended approach is a scheduled basal-bolus insulin regimen with 10 units of fixed-dose rapid-acting insulin before each meal, supplemented by correction doses according to the sliding scale provided, while strongly avoiding reliance on sliding scale insulin alone as the primary treatment strategy. 1, 2

Critical Problems with Sliding Scale Insulin as Primary Therapy

• The sole use of sliding scale insulin (SSI) in any setting is strongly discouraged and explicitly condemned by the American Diabetes Association. 1, 2
• Sliding scale insulin treats hyperglycemia reactively after it occurs rather than preventing it, leading to dangerous glucose fluctuations that exacerbate both hyper- and hypoglycemia. 2
• Randomized trials consistently demonstrate that basal-bolus approaches achieve glycemic control (mean blood glucose <140 mg/dL) in 68% of patients versus only 38% with sliding scale insulin alone. 2

Recommended Insulin Regimen Structure

Fixed Dose Component (Scheduled Insulin)

• Administer 10 units of rapid-acting insulin (such as lispro, aspart, or glulisine) subcutaneously 0-15 minutes before each of the three main meals. 3, 4
• This fixed dose provides scheduled nutritional (prandial) coverage to manage the expected postprandial glucose rise from meals. 1, 3

Correction Dose Component (Sliding Scale)

• Use the sliding scale ONLY as supplemental correction insulin in addition to the fixed scheduled doses, not as monotherapy: 1, 2
  • Blood glucose 61-150 mg/dL: No additional insulin needed
  • Blood glucose 151-200 mg/dL: Add 2 units
  • Blood glucose 201-250 mg/dL: Add 4 units
  • Blood glucose 251-300 mg/dL: Add 6 units
  • Blood glucose 301-350 mg/dL: Add 8 units
  • Blood glucose 351-400 mg/dL: Add 10 units

Hypoglycemia Management

• For blood glucose 0-60 mg/dL: Treat immediately with 15 grams of fast-acting carbohydrate (such as glucose tablets, juice, or regular soda), recheck in 15 minutes, and hold the insulin dose. 3

Essential Basal Insulin Component

• This regimen is incomplete without basal (long-acting) insulin coverage. 1, 3
• A basal-bolus insulin regimen with basal, nutritional, and correction components is the preferred treatment for patients with good nutritional intake. 1
• For patients requiring insulin therapy, start basal insulin at 10 units once daily or 0.1-0.2 units/kg body weight, administered at the same time each day. 3
• The total daily insulin dose should typically be divided approximately 50% as basal insulin and 50% as prandial insulin for optimal glycemic control. 3, 2

Monitoring and Titration Requirements

• Check blood glucose immediately before each meal to determine the correction dose needed in addition to the fixed 10 units. 3
• Target premeal blood glucose of 80-130 mg/dL and postprandial glucose <180 mg/dL. 1, 5
• If correction doses are frequently required (more than 2-3 times per week at the same meal), increase the scheduled fixed insulin dose for that meal by 1-2 units or 10-15%. 3
• Adjust insulin doses every 3 days based on glucose patterns to achieve glycemic targets. 3, 5

Critical Pitfalls to Avoid

• Never rely on sliding scale insulin alone without scheduled basal and prandial insulin, as this approach is associated with clinically significant hyperglycemia and poor outcomes. 1, 2
• Never administer rapid-acting insulin at bedtime using the sliding scale, as this significantly increases nocturnal hypoglycemia risk. 3
• Do not continue this regimen unchanged if glucose control remains poor—adjust the fixed doses upward rather than relying solely on increasing correction doses. 2
• If hypoglycemia occurs without clear cause, reduce the insulin dose by 10-20% immediately. 3

Foundation Therapy Considerations

• Continue metformin unless contraindicated, as it reduces total insulin requirements and provides complementary glucose-lowering effects. 3, 4
• Ensure the patient receives education on proper insulin injection technique, site rotation, hypoglycemia recognition and treatment, and self-monitoring of blood glucose. 3

When to Intensify Therapy

• If fasting glucose remains ≥180 mg/dL despite this regimen, increase basal insulin by 4 units every 3 days until fasting glucose reaches 80-130 mg/dL. 3
• If postprandial glucose consistently exceeds 180 mg/dL despite the fixed 10-unit doses, increase the fixed prandial insulin dose by 1-2 units for that specific meal. 3
• When basal insulin exceeds 0.5 units/kg/day without achieving glycemic targets, further intensification of prandial insulin becomes more appropriate than continuing to escalate basal insulin alone. 3