Insulin Therapy Guidelines

Introduction to Insulin Dosage

• Total daily insulin requirements (basal + prandial) generally range from 0.4-1.0 units/kg/day for patients with diabetes, according to the American Diabetes Association 1
• Higher insulin requirements are common during puberty, pregnancy, and medical illness, as stated by the American Diabetes Association 1
• Doses exceeding 0.5 units/kg/day should trigger reevaluation of the treatment plan, as indicated by the American Diabetes Association 1

Concentrated Insulin Formulations

• Concentrated insulin formulations, such as U-300 glargine (3× concentration of U-100) and U-200 degludec (2× concentration of U-100), may be more appropriate for high-dose patients, as recommended by the American Diabetes Association 2
• The benefits of concentrated insulins for high-dose patients include more comfortable injections (less volume), fewer injections to achieve target dose, and improved treatment adherence, according to the American Diabetes Association 2

Insulin Therapy Adjustments

• Starting doses of basal insulin should be estimated based on body weight (0.1–0.2 units/kg/day) and degree of hyperglycemia, as recommended by the American Diabetes Association 3
• Clinical signals of overbasalization include basal dose greater than 0.5 units/kg, high bedtime-morning glucose differential, hypoglycemia, and high variability, prompting reevaluation of the glucose-lowering treatment plan 3, 4
• If 50% of fasting blood glucose values are over target, the insulin regimen should be adjusted by increasing the dose by 2 units, and if more than 2 fasting blood glucose values per week are <80 mg/dL, the insulin regimen should be adjusted by decreasing the dose by 2 units 5

Hypoglycemia Management

• For confirmed hypoglycemia, administering 15-20g of fast-acting carbohydrate is recommended, with blood glucose rechecked after 15 minutes 6, 4
• If blood glucose remains <100 mg/dL, repeat treatment, and for severe cases with altered consciousness, administer IV glucose or glucagon 6
• Target blood glucose above 100 mg/dL (5.6 mmol/L) before bedtime to minimize the risk of nocturnal hypoglycemia 6
• Teach patients to recognize early signs of hypoglycemia, ensure patients understand the importance of regular meals when on insulin, and instruct patients to always carry rapid-acting carbohydrates 6

Special Considerations

• Patients with high insulin resistance or requiring high volumes may benefit from a split dosing approach, although the optimal strategy is not well established 1
• Consider less aggressive targets (A1C 7-8%) for patients at higher risk of hypoglycemia, and be aware that they may present with atypical hypoglycemia symptoms, as suggested by the American Diabetes Association 5
• Elderly patients are at higher risk for hypoglycemia and may present with atypical symptoms, including hallucinations 6
• Patients with renal impairment may have prolonged insulin action and require dose reduction 6
• Patients with visual impairment may have overlapping Charles Bonnet Syndrome (CBS) hallucinations that can be misattributed to hypoglycemia, with the following characteristics:

7

Patient Education and Follow-up

• Schedule frequent follow-ups for patients with a history of hypoglycemia, monitor HbA1c, and adjust treatment goals to minimize hypoglycemia risk 8
• Consider HbA1c target of 7-8% rather than <7% in patients prone to hypoglycemia 8
• Implement more frequent blood glucose monitoring, especially during nighttime, and consider continuous glucose monitoring for patients with recurrent hypoglycemia 6
• Consider insulin pump therapy for more physiologic insulin delivery in patients with recurrent severe hypoglycemia 9