Appropriate Actrapid Dose for Pre-Dinner Blood Glucose of 331 mg/dL
For a pre-dinner blood glucose of 331 mg/dL, administer 2-4 units of Actrapid (regular human insulin) as a correction dose, based on the most recent American Diabetes Association guidelines for simplified sliding scale insulin in older adults. 1
Evidence-Based Dosing Recommendation
The 2024 American Diabetes Association guidelines provide specific sliding scale recommendations for premeal hyperglycemia management:
- For premeal glucose >250 mg/dL but <350 mg/dL: Give 2 units of short- or rapid-acting insulin 1
- For premeal glucose >350 mg/dL: Give 4 units of short- or rapid-acting insulin 1
Since your patient's blood glucose is 331 mg/dL (falling between these thresholds), the appropriate dose is 2 units of Actrapid, with consideration for 4 units if the patient has been requiring higher insulin doses or has significant insulin resistance. 1
Important Clinical Context
Actrapid is a short-acting regular human insulin that should be administered 30 minutes before the meal to allow for proper onset of action. 2, 3 This differs from rapid-acting insulin analogues (lispro, aspart, glulisine) which can be given immediately before eating. 1
Timing Considerations
- Administer Actrapid 30 minutes before dinner to optimize postprandial glucose control 3
- Monitor blood glucose 2-4 hours after administration to assess effectiveness and watch for hypoglycemia 2
Beyond Immediate Correction
This sliding scale approach should only be temporary. 1 The guidelines explicitly state to "stop sliding scale when not needed daily." 1
If Hyperglycemia Persists
If the patient requires correction doses daily, you must address the underlying insulin regimen:
- Increase basal insulin by 2 units every 3-7 days until fasting glucose reaches 90-150 mg/dL 1
- Consider adding scheduled prandial insulin at the largest meal, starting at 4 units or 10% of basal dose 2
- Maintain any organ-protective medications (SGLT2 inhibitors, GLP-1 receptor agonists, metformin) 1, 2
Critical Safety Considerations
Monitor for hypoglycemia 2-4 hours post-injection when Actrapid action peaks. 2 The risk is particularly high if:
- The patient has impaired renal function (prolongs insulin action) 1
- Caloric intake is uncertain or reduced 4, 5
- The patient is on sulfonylureas (should be discontinued when using complex insulin regimens) 1, 2
Common Pitfalls to Avoid
- Do not use Actrapid at bedtime - short-acting insulin should not be given before sleep due to nocturnal hypoglycemia risk 1
- Do not rely solely on sliding scale insulin without optimizing basal coverage - this approach is ineffective for long-term management 2, 4
- Do not delay regimen adjustment if correction doses are needed repeatedly - this represents therapeutic inertia 1, 2
Target Blood Glucose Goals
The premeal target should be 90-150 mg/dL (5.0-8.3 mmol/L) for most patients, though this may be adjusted based on overall health status, age, and risk of hypoglycemia. 1 For hospitalized patients, a less stringent target of 140-180 mg/dL is appropriate. 4, 5