Maximum Dose of Novolog for Sliding Scale Insulin
There is no absolute maximum dose of Novolog (insulin aspart) for sliding scale regimens, but current guidelines recommend simplified sliding scale protocols with 2-4 units as correction doses for specific glucose thresholds rather than escalating to higher doses.
Guideline-Recommended Sliding Scale Dosing
The American Diabetes Association provides specific sliding scale recommendations for rapid-acting insulins like Novolog:
- For premeal glucose >250 mg/dL (>13.9 mmol/L): Give 2 units of rapid-acting insulin 1, 2
- For premeal glucose >350 mg/dL (>19.4 mmol/L): Give 4 units of rapid-acting insulin 1, 2
These represent the standard correction doses in simplified sliding scale protocols, particularly for older adults 1.
Important Context About Sliding Scale Limitations
Sliding scale insulin as monotherapy is ineffective and should not be the primary insulin strategy 1. The traditional approach of using only sliding scale insulin without basal coverage has been shown to be ineffective when used alone in patients with established insulin requirements 1.
Why Higher Doses Are Not Recommended
- Sliding scale insulin is a "reactive" approach that treats hyperglycemia after it occurs rather than preventing it 1
- Studies show sliding scale achieves good glycemic control in only 2-10% of hospitalized patients 3
- The approach leads to widely variable and often ineffectual outcomes 3
- Correction doses should prompt adjustment of scheduled insulin rather than escalating sliding scale doses 1, 2
Proper Insulin Dosing Strategy
Instead of relying on high-dose sliding scale corrections, the evidence supports:
Initial Prandial Insulin Dosing
- Start with 4 units per dose, 0.1 units/kg, or 10% of basal insulin dose 2
- Administer at the largest meal or meal with greatest postprandial excursion 1, 2
Titration Approach
- Increase by 1-2 units or 10-15% twice weekly based on glucose response 2
- If correction doses are frequently required, increase the scheduled insulin doses rather than continuing high-dose corrections 1
When to Stop Sliding Scale
- Discontinue sliding scale when not needed daily 1, 2
- This is particularly important in older adults to reduce medication burden 2
Clinical Pitfalls to Avoid
- Do not use rapid-acting insulin at bedtime to prevent nocturnal hypoglycemia 1, 2
- Avoid continuing the same sliding scale throughout hospitalization without modification, even when control remains poor 1
- Do not escalate sliding scale doses indefinitely—this indicates need for scheduled insulin adjustment 1
Special Population Considerations
For older adults, use more conservative targets (90-150 mg/dL) and lower correction doses to reduce hypoglycemia risk 1, 2. The simplified sliding scale with 2-4 unit corrections is specifically designed for this population 1.
For hospitalized patients requiring higher insulin doses, transition to basal-bolus therapy rather than escalating sliding scale corrections 1. Weight-based dosing of 0.4-0.5 units/kg/day in basal-bolus regimens is more effective than sliding scale alone 1.