NPH Insulin Dosing
Start NPH insulin at 10 units per day OR 0.1-0.2 units/kg per day, administered at bedtime for standard diabetes management or in the morning specifically for steroid-induced hyperglycemia. 1
Standard Initiation Protocol
Starting Dose Calculation
- Fixed dose approach: Begin with 10 units per day 1
- Weight-based approach: 0.1-0.2 units/kg per day 1
- For a 70 kg patient, this translates to 7-14 units daily 1
Timing of Administration
- Bedtime dosing is preferred for standard type 2 diabetes with fasting hyperglycemia, as it provides superior glycemic control compared to morning administration 2
- Morning dosing is specifically recommended for steroid-induced hyperglycemia to match the peak hyperglycemic effect of glucocorticoids 1, 3
Titration Strategy
Evidence-Based Adjustment Algorithm
- Increase by 2 units every 3 days until fasting plasma glucose reaches target without hypoglycemia 1
- Set individualized fasting plasma glucose goals based on patient characteristics 1
- This systematic approach prevents therapeutic inertia while maintaining safety 1
Hypoglycemia Management
- If hypoglycemia occurs, determine the underlying cause 1
- Reduce dose by 10-20% if no clear precipitating factor is identified 1
- Monitor closely for recurrent episodes requiring further adjustment 1
Advancing to More Complex Regimens
When Basal Insulin Alone Is Insufficient
- If A1C remains above goal despite adequate basal insulin titration, consider adding prandial insulin 1
- Convert to twice-daily NPH by using 80% of the current bedtime dose as the total daily NPH dose 1
Adding Prandial Coverage
- Start with 4 units of rapid-acting insulin at the largest meal or meal with greatest postprandial glucose excursion 1
- Alternatively, use 10% of the basal insulin dose as the starting prandial dose 1
- If A1C is <8% when adding prandial insulin, consider reducing basal dose by 4 units or 10% 1
Special Clinical Scenarios
Steroid-Induced Hyperglycemia
- NPH is the preferred insulin formulation due to its intermediate-acting profile that peaks at 4-6 hours, aligning with glucocorticoid effects 3
- Administer in the morning to coincide with peak steroid effect 1, 3
- Higher doses (40-60% above standard) are often required with high-dose glucocorticoids 3
- Reduce NPH by 10-20% when tapering steroids to prevent hypoglycemia 3
Continuous Tube Feeding
- Administer NPH every 8 or 12 hours to cover continuous nutritional needs 4
- Calculate nutritional insulin as approximately 1 unit per 10-15 grams of carbohydrate in the formula 4
- The midnight dose should be approximately 80% of daytime doses due to increased overnight insulin sensitivity 4
- Critical safety point: If tube feeding is interrupted, immediately start 10% dextrose infusion to prevent hypoglycemia, as NPH continues working for 12-18 hours 4
Common Pitfalls and How to Avoid Them
Avoiding Therapeutic Inertia
- Reassess and modify the regimen every 3-6 months if glycemic targets are not met 1
- Do not delay intensification when basal insulin is titrated to >0.5 units/kg/day without achieving A1C goals 1
Recognizing Overbasalization
- Monitor for clinical signals: elevated bedtime-to-morning glucose differential, postprandial-to-preprandial differential, hypoglycemia, or high glucose variability 1
- These indicate the need for adjunctive therapies rather than further basal insulin increases 1
Medication Continuation
- Maintain metformin when initiating or advancing insulin therapy 1
- Continue GLP-1 receptor agonists when adding basal insulin, as they complement insulin action and mitigate weight gain 1
Cost Considerations
- NPH insulin is significantly less expensive than long-acting basal analogs (glargine, detemir) 1
- Long-acting analogs offer modestly less overnight hypoglycemia and possibly slightly less weight gain with detemir, but NPH remains highly effective when properly dosed 1
- The choice should balance cost-effectiveness with individual patient factors including hypoglycemia risk 1