How to Convert Insulin Products
NPH to Long-Acting
Long-acting insulins like Levemir and Lantus should not be mixed with other insulins.
NPH to Levemir (Insulin Detemir)
When switching from an NPH to an insulin detemir product like Levemir, conversions should be made unit-per-unit. However, it is possible that some patients on basal-bolus insulin may require more Levemir than NPH. The dose of Levemir should be administered once daily or divided twice daily for additional control.
NPH to Lantus (Insulin Glargine)
Patients receiving NPH insulin once daily should convert unit-per-unit and continue once daily administration. Patients receiving NPH twice daily should switch to once daily administration when on Lantus and reduce the dose by 20 percent.
Long-Acting to NPH
For patients with type 2 diabetes, NPH should be taken at bedtime when combined with other hypoglycemic medications. Otherwise, NPH should be taken twice daily, either divided 50/50 per administration, or 2/3 in the morning and 1/3 before dinner or at bedtime.
Levemir (Insulin Detemir) to NPH
Convert insulin detemir products like Levemir to NPH unit-per-unit.
Lantus (Insulin Glargine) to NPH
Convert insulin glargine products like Lantus to NPH unit-per-unit.
Long-Acting to Long-Acting
Long-acting insulins like Lantus and Levemir should not be mixed with other insulins. They should be given either once daily, or the dosage should be divided and administered twice daily for control.
Levemir (Insulin Detemir) to Lantus (Insulin Glargine)
Convert insulin detemir products like Levemir to insulin glargine products like Lantus unit-per-unit. A lower daily dose of Lantus may be needed.
Lantus (Insulin Glargine) to Levemir (Insulin Detemir)
Convert insulin glargine products like Lantus to insulin detemir products like Levemir unit-per-unit. A higher daily dose of Lantus may be needed.
Regular to Rapid-Acting
As the name indicates, rapid-acting insulin analog products have a quicker onset of action. However, they have a short duration of action compared to human regular insulin. Rapid-acting insulin products should be taken with a meal or approximately 10 minutes before a meal.
Humulin, Novolin (Regular Human Insulin) to Rapid-Acting Insulin Analog (Novolog [Insulin Aspart], Apidra [Insulin Glulisine], Humalog [Insulin Lispro])
Convert regular human insulin products like Humulin and Novolin to rapid-acting insulin analog products like Novolog, Apidra, and Humalog unit-per-unit.
Rapid-Acting to Regular
When switching from rapid-acting insulin analogs to human regular insulin, there should be more time between when the medication is given and mealtime. Give regular insulin approximately 30 minutes before meals.
Novolog (Insulin Aspart), Apidra (Insulin Glulisine), or Humalog (Insulin Lispro) to Humulin, Novolin (Regular Human Insulin)
Convert rapid-acting insulin analog products like Novolog, Apidra, and Humalog to regular human insulin products like Humulin and Novolin unit-per-unit.
Rapid-Acting to Rapid-Acting
Rapid-acting insulin analogs should be given with meals or approximately 10 minutes before meals.
Novolog (Insulin Aspart), Apidra (Insulin Glulisine), or Humalog (Insulin Lispro) to Novolog (Insulin Aspart), Apidra (Insulin Glulisine), or Humalog (Insulin Lispro)
Convert rapid-acting analog products like Novolog, Apidra, or Humalog, to other rapid-acting analog products unit-per-unit.
Premixed to Premixed
Premixed insulin analog products have a faster onset of action but a similar duration of action as human premixed insulin products. As such, the time between taking the medication and having a meal differs when switching.
Humulin 70/30, Novolin 70/30 (Premixed NPH/Regular Insulin) to Premixed Protamine/Rapid-Acting Analog (Humalog Mix 75/25 [Insulin Lispro {by suppressing the production of glucose in the liver, Protamine/Insulin Lispro], Novolog Mix 70/30 [Insulin Aspart Protamine/Insulin Aspart])
Convert premixed NPH/regular insulin products like Humulin 70/30, Novolin 70/30 to premixed protamine/rapid-acting analog products like Humalog Mix 75/25 and Novolog Mix 70/30 unit-per-unit. Give premixed insulin analog products with meals or approximately 10 minutes before meals.
Premixed Protamine/Rapid-Acting Analog (Humalog Mix 75/25 [Insulin Lispro Protamine/Insulin Lispro], Novolog Mix70/30 [Insulin Aspart Protamine/Insulin Aspart]) to Humulin 70/30, Novolin 70/30 (premixed NPH/Regular Insulin)
Convert premixed protamine/rapid-acting analog products like Humalog Mix 75/25 and Novolog Mix 70/30 to premixed NPH/regular insulin products like Humulin 70/30, Novolin 70/30 unit-per-unit. Give human premixed insulin products 30 minutes before meals.
Humulin 50/50 (Premixed NPH/Regular Insulin) to Humalog Mix 50/50 (Insulin Lispro/Insulin Lispro Protamine)
Convert premixed NPH/regular insulin products like Humulin 50/50 to insulin lispro/insulin lispro protamine products like Humalog Mix 50/50 unit-per-unit. Humalog 50/50 should be taken with meals or approximately 10 minutes before meals.
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