What is the typical starting dose and administration schedule for NPH (Neutral Protamine Hagedorn) insulin?

NPH Insulin: Starting Dose and Administration Schedule

For type 2 diabetes, initiate NPH insulin at 10 units per day or 0.1-0.2 units/kg/day (approximately 7-14 units for a 70 kg patient), administered once daily at bedtime, in conjunction with metformin. 1

Standard Dosing for Type 2 Diabetes

Basal insulin initiation:

• Start with 10 units per day as a fixed dose, OR 1
• Calculate 0.1-0.2 units/kg/day based on body weight and degree of hyperglycemia 1
• Administer as a single bedtime injection when used as basal insulin 1

Titration strategy:

• Equip patients with a self-titration algorithm based on self-monitoring of blood glucose 1
• Adjust doses frequently based on fasting glucose targets 1

Alternative Dosing Schedules

Twice-daily NPH regimen:

• When combined with regular insulin in a 70/30 premixed formulation, administer before breakfast and before dinner 1
• This provides both basal and prandial coverage with each injection 1

Three-times-daily NPH:

• For patients on continuous enteral/parenteral nutrition, administer NPH every 8 or 12 hours to cover nutritional requirements 1
• Calculate as 1 unit of insulin for every 10-15 grams of carbohydrate in the feeding formula 1

Special Clinical Contexts

Steroid-induced hyperglycemia:

• Administer NPH in the morning (not bedtime) to match the peak hyperglycemic effect of glucocorticoids 2, 3
• Start with 0.1-0.2 units/kg/day as the initial dose 2
• NPH peaks at 4-6 hours, which aligns with steroid-induced hyperglycemia timing 1, 2
• For high-dose glucocorticoids, expect to increase doses by 40-60% or more above standard requirements 1, 3

Hospitalized patients:

• Continue basal insulin in patients with type 1 diabetes even if NPO to prevent diabetic ketoacidosis 1
• Add correctional insulin subcutaneously every 6 hours with regular human insulin 1
• If enteral nutrition is interrupted, start dextrose infusion immediately to prevent hypoglycemia 1, 4

Important Clinical Considerations

Advantages of NPH:

• Less expensive than long-acting basal analogs (glargine, detemir) 1
• Effective when administered twice daily for patients requiring more intensive coverage 5

Disadvantages compared to long-acting analogs:

• Peak insulin activity occurs 4-6 hours after administration, increasing nocturnal hypoglycemia risk 6
• More variable pharmacokinetic profile compared to glargine or detemir 7
• When used as basal insulin, long-acting analogs (U-100 glargine or detemir) can be used instead of NPH for more predictable glucose control 1

Common Pitfalls to Avoid

• Do not use NPH alone for steroid-induced hyperglycemia at bedtime - morning administration is essential to match steroid timing 2, 3
• Do not forget basal insulin in type 1 diabetes patients who are NPO or have feeding interruptions 1
• Avoid relying solely on correctional insulin without adequate basal coverage, as this leads to poor glycemic control 1
• Monitor closely for hypoglycemia when NPH is given at bedtime due to peak action during sleep hours 6
• Coordinate meal delivery with insulin administration in hospitalized patients to prevent hypo- and hyperglycemic events 1