What if my patient is not absorbing 55 units of NPH (Neutral Protamine Hagedorn) insulin?

Managing a Patient Not Absorbing 55 Units of NPH Insulin

If your patient is not absorbing 55 units of NPH insulin, consider switching from evening NPH to a basal analog insulin, as this approach can improve absorption issues and provide more consistent glycemic control. 1

Evaluation of Poor NPH Absorption

• Assess for proper injection technique, as improper administration can lead to variable absorption 2
• Check for lipohypertrophy at injection sites, which can significantly reduce insulin absorption 1
• Evaluate if the NPH insulin suspension was properly mixed before administration, as inadequate mixing can cause dosing inconsistencies 2
• Consider if the patient is injecting into areas with poor subcutaneous blood flow or scar tissue 2

Recommended Management Approach

Switch to Basal Analog Insulin

• Convert from NPH to a long-acting basal analog insulin (glargine, detemir, or degludec) which has:
  • Lower intraindividual variability compared to NPH insulin 2
  • More consistent absorption profile 3
  • Reduced risk of hypoglycemia, especially nocturnal episodes 1

Dosing Conversion

• When switching from NPH to a basal analog:
  • Start with 80% of the current NPH dose to avoid hypoglycemia 1
  • Consider once-daily dosing with long-acting analogs instead of twice-daily NPH 1
  • Monitor blood glucose closely during transition and adjust as needed 1

Alternative NPH Administration Strategies

If basal analog is not an option:

• Consider splitting the NPH dose into twice-daily administration 1
  • Use 2/3 of the total dose in the morning and 1/3 in the evening 1
  • This approach provides more consistent insulin coverage throughout the day 4
• Rotate injection sites systematically to prevent lipohypertrophy 2
• Ensure proper mixing of NPH suspension before each injection 2

Special Considerations

For Patients on Steroids

• If the patient is on steroids, morning administration of NPH is particularly important to counteract steroid-induced hyperglycemia 5, 4
• For steroid-induced hyperglycemia, consider a morning-weighted NPH dosing schedule 5, 4

For Patients with Significant Absorption Issues

• Consider adding a GLP-1 receptor agonist if not already using one, as this can improve glycemic control while potentially reducing insulin requirements 1
• For persistent absorption problems, evaluate for a fixed-ratio combination product of basal insulin and GLP-1 RA (IDegLira or iGlarLixi) 1

Monitoring and Follow-up

• Assess adequacy of insulin dose at every visit 1
• Monitor for clinical signals of overbasalization (elevated bedtime-to-morning differential, hypoglycemia, high glucose variability) 1
• For hypoglycemia, determine the cause; if no clear reason is found, lower the corresponding dose by 10-20% 1

Common Pitfalls to Avoid

• Failing to properly mix NPH insulin before administration can lead to inconsistent dosing 2
• Continuing to increase NPH dose despite absorption issues may lead to unpredictable hypoglycemia when absorption suddenly improves 2
• Ignoring injection site rotation, which can lead to lipohypertrophy and variable absorption 2
• Maintaining evening NPH dosing when morning administration might be more appropriate, especially for patients on steroids 5, 4