Write prescription instructions for a rapid‑acting insulin (insulin lispro (Humalog), insulin aspart (Novolog), or insulin glulisine (Apidra)) to be used only as a correction dose in a patient with type 2 diabetes who is already on basal insulin.

Prescription Instructions for Rapid-Acting Insulin as Correction Doses in Type 2 Diabetes

Start with 2 units of rapid-acting insulin (lispro, aspart, or glulisine) when your blood glucose is above 250 mg/dL before meals, and 4 units when above 350 mg/dL, but only as a supplement to your scheduled basal insulin—never use correction doses alone. 1

Critical Foundation: Correction Insulin Must Supplement Scheduled Insulin

• Correction (sliding-scale) insulin should never be used as your only insulin therapy—this approach is condemned by all major diabetes guidelines because it treats high blood sugar reactively after it occurs rather than preventing it 1, 2
• Only 38% of patients using correction insulin alone achieve adequate glucose control, compared to 68% using scheduled basal-bolus therapy 1, 2
• You must be on a scheduled basal insulin regimen (such as glargine, detemir, or degludec once daily) before adding correction doses 1, 2

Simplified Correction Dose Protocol

When to inject correction insulin (in addition to your scheduled insulin):

• Blood glucose 250–350 mg/dL before a meal: Inject 2 units of rapid-acting insulin 1, 2
• Blood glucose above 350 mg/dL before a meal: Inject 4 units of rapid-acting insulin 1, 2
• Blood glucose below 250 mg/dL: No correction dose needed 1

Timing and Administration

• Inject rapid-acting insulin 0–15 minutes before eating—ideally immediately before your meal 1, 3
• Never inject rapid-acting insulin at bedtime as a correction dose alone, as this dramatically increases your risk of dangerous low blood sugar during the night 1, 2
• Use subcutaneous injection in your abdomen, thigh, or upper arm, rotating sites to prevent tissue damage 1

When Your Correction Doses Signal a Problem

• If you need correction doses more than twice per week, this means your scheduled basal insulin dose is too low and needs to be increased 1, 2
• Frequent correction doses are a red flag that your diabetes regimen is inadequate—contact your provider to adjust your scheduled insulin rather than relying on corrections 1, 2
• When your basal insulin reaches 0.5 units/kg/day (roughly 35–40 units for a 70 kg person) without controlling your blood sugar, you likely need scheduled mealtime insulin, not just correction doses 1, 2

Safety Monitoring

• Check your blood glucose before each meal to determine if a correction dose is needed 1, 2
• If your glucose drops below 70 mg/dL, immediately eat 15 grams of fast-acting carbohydrate (4 glucose tablets, ½ cup juice, or 1 tablespoon honey), recheck in 15 minutes, and repeat if needed 1, 2
• If you experience unexplained low blood sugar, reduce your next insulin dose by 10–20% and contact your provider 1, 2

Individualized Correction Factor (Advanced Option)

• For more precise dosing, your provider can calculate your insulin sensitivity factor (ISF) using the formula: 1500 ÷ your total daily insulin dose 1, 2
• Your correction dose would then be: (Current glucose – Target glucose of 125 mg/dL) ÷ ISF 1, 2
• This method requires stable total daily insulin doses and should be recalculated every few weeks as your insulin needs change 1

Critical Pitfalls to Avoid

• Do not use correction insulin as your only diabetes treatment—this approach fails in the majority of patients and is considered dangerous 1, 2
• Do not inject rapid-acting insulin at bedtime unless you can monitor closely, as nocturnal hypoglycemia risk is unacceptably high 1, 2
• Do not ignore the need for scheduled insulin adjustments when you require frequent correction doses—this perpetuates poor control 1, 2
• Do not "stack" correction doses by giving another dose within 3–4 hours, as insulin from the previous dose is still active 1

When to Contact Your Provider Immediately

• Blood glucose remains above 300 mg/dL despite two correction doses 1, 2
• You develop nausea, vomiting, abdominal pain, or confusion with high blood sugar (possible diabetic ketoacidosis) 1, 2
• You experience blood glucose below 54 mg/dL or severe hypoglycemia requiring assistance 1, 2
• You need correction doses more than 3–4 times per week, indicating your scheduled insulin regimen is inadequate 1, 2