What is the initial recommendation for insulin therapy in patients with diabetes?

Initial Insulin Therapy Recommendation

For patients with type 2 diabetes requiring insulin initiation, start with basal insulin at 10 units once daily or 0.1-0.2 units/kg body weight, administered at the same time each day, typically in conjunction with metformin. 1, 2, 3

Starting Dose by Clinical Presentation

Type 2 Diabetes - Metabolically Stable

• Initial dose: 10 units once daily OR 0.1-0.2 units/kg body weight 1, 2, 3
• Use in patients with A1C <8.5% without ketosis or severe symptoms 1
• Continue metformin unless contraindicated 1, 2
• Long-acting basal analogs (glargine, detemir, degludec) are preferred over NPH insulin 1, 4

Type 2 Diabetes - Marked Hyperglycemia

• For A1C ≥9% or blood glucose ≥300-350 mg/dL: Consider higher starting doses of 0.3-0.4 units/kg/day 1, 2
• For A1C ≥8.5% with symptoms (polyuria, polydipsia, weight loss): Start basal insulin while initiating metformin 1
• For A1C 10-12% with catabolic features: Start basal-bolus insulin regimen immediately 1, 2

Type 1 Diabetes

• Total daily dose: 0.4-1.0 units/kg/day, with approximately one-third as basal insulin 2, 3
• Must be combined with rapid-acting mealtime insulin from the start 1, 3
• Typical dose for metabolically stable patients is 0.5 units/kg/day 2

Pediatric Type 2 Diabetes

• For A1C ≥8.5% without acidosis: Start 0.5 units/kg/day basal insulin plus metformin 1
• With ketosis/ketoacidosis: Initiate insulin immediately to correct metabolic derangement, then add metformin 1

Titration Protocol

Increase basal insulin by 2-4 units (or 10-15%) every 3 days until fasting blood glucose reaches 80-130 mg/dL. 1, 2

Specific Titration Algorithm

• If fasting glucose ≥180 mg/dL: Increase by 4 units every 3 days 2
• If fasting glucose 140-179 mg/dL: Increase by 2 units every 3 days 2
• If fasting glucose <80 mg/dL (more than 2 values/week): Decrease by 2 units 2
• If hypoglycemia occurs: Reduce dose by 10-20% 2, 5

Administration Guidelines

• Timing: Once daily at the same time each day (can be any time, but consistency is critical) 1, 3
• Injection sites: Rotate between abdomen, thigh, or deltoid within the same region 3
• Do NOT mix or dilute insulin glargine with any other insulin or solution 1, 3
• Do NOT administer intravenously or via insulin pump 3

When to Advance Beyond Basal Insulin

If after 3-6 months of basal insulin optimization, fasting glucose reaches target (80-130 mg/dL) but A1C remains above goal, add prandial insulin rather than continuing to escalate basal insulin. 1, 2

Critical Threshold

• When basal insulin exceeds 0.5 units/kg/day and A1C remains elevated, adding mealtime insulin is more appropriate than further basal insulin increases 1, 2
• Start prandial insulin with 4 units before the largest meal OR 10% of basal dose 1, 2

Essential Patient Education Requirements

• Self-monitoring of fasting blood glucose daily during titration 1, 2
• Recognition and treatment of hypoglycemia 1, 2
• Proper injection technique and site rotation to prevent lipodystrophy 1, 3
• "Sick day" management rules 2
• Insulin storage and handling 2

Critical Pitfalls to Avoid

• Delaying insulin initiation in patients not achieving glycemic goals with oral medications leads to prolonged hyperglycemia and increased complication risk 1, 5
• Using insulin as a threat or describing it as personal failure undermines patient acceptance 1
• Overbasalization: Continuing to increase basal insulin beyond 0.5-1.0 units/kg/day without addressing postprandial hyperglycemia causes suboptimal control and increased hypoglycemia 2
• Abruptly discontinuing oral medications when starting insulin risks rebound hyperglycemia 6
• Injecting into areas of lipodystrophy results in erratic absorption and hyperglycemia 3, 6

Foundation Therapy

Metformin should be continued when initiating insulin therapy unless contraindicated, as it reduces weight gain, lowers insulin requirements, and decreases hypoglycemia risk. 1, 2, 6