Prescribing Insulin Glargine and Insulin Glulisine in Hospitalized Patients
For most noncritically ill hospitalized adults with adequate oral intake, use a basal-bolus regimen with insulin glargine once daily and insulin glulisine before each meal, starting at a total daily dose of 0.3-0.5 U/kg (split 50% basal, 50% prandial divided three times daily). 1
Initial Dosing Algorithm
For Insulin-Naive Patients or Low-Dose Home Insulin Users
- Calculate total daily dose (TDD): 0.3-0.5 U/kg body weight 1
- Distribute as follows:
Example: For a 100 kg patient:
- TDD = 40 units (0.4 U/kg)
- Glargine: 20 units once daily
- Glulisine: ~7 units before each meal
- Plus correction doses as needed
Dose Adjustments for High-Risk Patients
Reduce the starting dose to 0.1-0.3 U/kg for patients at increased hypoglycemia risk: 1
- Age >65 years
- Renal failure
- Hepatic impairment
- Poor or uncertain oral intake
- Thin or normal body weight
For Patients Already on High-Dose Insulin at Home
If home insulin dose ≥0.6 U/kg/day, reduce total daily dose by 20% on hospital admission to prevent hypoglycemia. 1
Alternative Regimen: Basal-Plus Approach
For patients with mild hyperglycemia (glucose <200 mg/dL), decreased oral intake, or undergoing surgery, use a basal-plus regimen instead: 1
- Glargine: 0.1-0.25 U/kg once daily 1
- Glulisine: Correction doses only before meals (or every 6 hours if NPO) for glucose >140 mg/dL 1, 2
This approach provides similar glycemic control to basal-bolus but with lower hypoglycemia risk, particularly in surgical patients. 3, 2, 4 Research demonstrates that basal-plus resulted in comparable mean daily glucose control to basal-bolus (152.6 vs 160.4 mg/dL) with similar hypoglycemia rates in general medical and surgical patients. 2, 4
Timing of Administration
Administer insulin glargine once daily at a consistent time—bedtime, pre-breakfast, or pre-dinner are all equally effective. 5 The FDA label data shows no significant difference in HbA1c reduction regardless of timing. 5
Give insulin glulisine 0-15 minutes before meals. 6 Studies show glulisine provides approximately 8 mg/dL better glucose control than regular insulin in hospitalized patients, with this benefit increasing after 4 days of therapy. 6
Critical Pitfalls to Avoid
Never Use Sliding Scale Insulin Alone
Do not use correction insulin (sliding scale) as monotherapy in hospitalized patients with established diabetes. 1 This outdated approach is condemned in guidelines and results in clinically significant hyperglycemia. 1 The exception is patients without diabetes who have mild stress hyperglycemia. 1
Avoid Premixed Insulin
Do not use premixed insulin (70/30) in the hospital setting—it carries an unacceptably high hypoglycemia risk. 1
Manage Patients Already on Home Insulin Glargine
For patients on glargine at home, continue the same basal insulin rather than switching to NPH, unless the home dose requires reduction for safety. 5 Unnecessary formulary switches increase medication errors and complicate discharge transitions. 7
Titration Strategy
Adjust basal insulin glargine based on fasting plasma glucose: 1, 8
- Target fasting glucose <110 mg/dL
- Target throughout-day glucose 110-180 mg/dL 9
Adjust prandial insulin glulisine based on pre-meal and 2-hour postprandial glucose values. 1, 8
Special Populations
Fasting or NPO Patients
For patients who are fasting or NPO, use basal-plus approach: 1
- Continue basal glargine at reduced dose (0.1-0.25 U/kg)
- Give correction glulisine every 6 hours for elevated glucose
- Hold scheduled prandial doses
Type 1 Diabetes
Never use sliding scale insulin alone in type 1 diabetes—these patients require basal insulin at all times. 1 Basal-bolus regimens are mandatory. 1, 10
Hypoglycemia Risk Management
The basal-bolus approach carries a 4-6 times higher hypoglycemia risk than sliding scale alone (though sliding scale provides inadequate glycemic control). 1 The incidence of mild hypoglycemia with basal-bolus is 12-30% in controlled settings. 1 To mitigate this risk, use lower starting doses in high-risk patients and consider basal-plus regimens for those with uncertain oral intake. 1
Combination with Other Medications
Continue metformin when combining with insulin—this reduces weight gain, lowers required insulin doses, and decreases hypoglycemia compared to insulin alone. 1, 8 Do not abruptly discontinue oral medications when starting insulin due to rebound hyperglycemia risk. 10