What is the optimal insulin regimen for a 40-year-old female patient with uncontrolled diabetes (Diabetes Mellitus), a high Hemoglobin A1c (HbA1c) level of 11.6, and insulin resistance, currently taking Lantus (Insulin Glargine) 20 units at bedtime and Humalog (Insulin Lispro) three times a day before meals with a sliding scale, and also has hypothyroidism?

Insulin Regimen Optimization for Severe Uncontrolled Type 2 Diabetes

This patient requires immediate and aggressive insulin intensification: increase Lantus to 40-50 units once daily (or split to 25 units twice daily) and increase Humalog to 10-12 units before each meal, with continued aggressive titration every 3 days until glucose targets are achieved. 1, 2

Rationale for Aggressive Approach

• With HbA1c of 11.6%, this patient has severe hyperglycemia requiring insulin as the primary treatment approach, as patients with HbA1c >10% need more potent glucose-lowering therapy regardless of individual glucose readings 1, 2
• The current total daily insulin dose of approximately 38 units (20 units Lantus + ~18 units Humalog) is grossly insufficient for a 257-lb (117 kg) patient, representing only 0.32 units/kg/day when she likely needs 0.6-1.0 units/kg/day for replacement therapy 3
• Therapeutic inertia—delaying insulin intensification despite inadequate control—leads to prolonged hyperglycemia and increased risk of complications 2

Specific Basal Insulin Adjustments

Lantus (Insulin Glargine) Dosing

• Increase Lantus from 20 units to 40-50 units once daily at bedtime initially, as the current dose is inadequate for her weight and degree of hyperglycemia 1
• Alternative approach: Split Lantus to twice daily dosing (25 units in morning, 25 units at bedtime) to provide more consistent 24-hour basal coverage, which may be necessary given the severe hyperglycemia 1
• Titrate upward by 2 units every 3 days until fasting glucose reaches 80-130 mg/dL 1
• For hypoglycemia, reduce dose by 10-20% and reassess the cause 1, 2

Specific Prandial Insulin Adjustments

Humalog (Insulin Lispro) Dosing

• Increase from 6 units to 10-12 units before each meal immediately, as the current dose is insufficient for HbA1c of 11.6% 1, 2
• The sliding scale approach is appropriate but the base dose needs substantial increase 1
• Titrate prandial insulin by 1-2 units or 10-15% every 3 days based on 2-hour postprandial glucose readings (target <180 mg/dL) 1, 2
• Continue the sliding scale corrections as ordered, but recognize these are adjunctive to adequate basal dosing 1

Critical Monitoring Requirements

• She must check blood glucose at minimum 4 times daily (fasting and before each meal) during this intensification period—non-negotiable for safe titration 1
• Add 2-hour postprandial checks at least once daily to assess prandial insulin adequacy 1
• Consider continuous glucose monitoring to identify glucose patterns and nocturnal hypoglycemia risk, especially given her non-adherence to checking glucose 2
• Reassess HbA1c in 3 months after achieving stable insulin doses 2

Expected Total Daily Insulin Requirements

• Target total daily insulin dose should be approximately 70-117 units/day (0.6-1.0 units/kg/day) for replacement therapy in a patient of her weight with this degree of hyperglycemia 3
• Split as 50% basal (35-58 units) and 50% prandial (35-58 units divided among three meals) 3
• The current regimen of ~38 units total is only one-third to one-half of what she likely needs 3

Alternative Regimen Consideration

• If she remains non-compliant with multiple daily injections, consider switching to premixed insulin (Humalog Mix 75/25) twice daily at breakfast and dinner, starting at 25-30 units per dose 1
• This reduces injection burden from 4 to 2 daily injections, which may improve adherence 1, 4
• However, premixed insulin offers less flexibility and may increase hypoglycemia risk compared to basal-bolus therapy 4

Adjunctive Therapy Considerations

• Ensure metformin is prescribed if not contraindicated, as it reduces all-cause mortality and cardiovascular events and should be continued with insulin 3
• Consider adding a GLP-1 receptor agonist (not a DPP-4 inhibitor) once insulin doses are optimized, as GLP-1 RAs provide superior glucose-lowering efficacy for HbA1c >10% and may reduce insulin requirements 2, 5
• GLP-1 RAs also promote weight loss, which would benefit this patient (BMI ~40) 5

Common Pitfalls to Avoid

• Do not focus solely on fasting glucose (330 mg/dL)—both fasting and postprandial glucose contribute to HbA1c of 11.6% 2
• Do not undertitrate insulin due to fear of hypoglycemia—with HbA1c this high, aggressive titration is necessary and hypoglycemia risk is actually lower until approaching target 1, 2
• Do not continue inadequate insulin doses for months—every month of uncontrolled hyperglycemia increases microvascular and macrovascular complication risk 1
• Address the hypothyroidism aggressively (levothyroxine increase from 125 to 150 mcg is appropriate), as uncontrolled hypothyroidism worsens insulin resistance and glycemic control 1

Patient Education Imperatives

• Prescribe glucagon for emergent hypoglycemia given the insulin intensification 1
• Educate on hypoglycemia recognition and treatment (15g fast-acting carbohydrate for glucose <70 mg/dL) 1
• Emphasize that blood glucose monitoring is non-negotiable for safe insulin titration—without it, she is at risk for both severe hyperglycemia and hypoglycemia 1
• Provide written titration instructions for self-adjustment between visits 1