What is the typical starting dose and titration schedule for basal insulin, such as glargine (insulin glargine) or detemir (insulin detemir), in patients with diabetes?

Basal Insulin Dosing and Titration

Starting Dose

For insulin-naïve patients with type 2 diabetes, initiate basal insulin (glargine or detemir) at 0.1-0.2 units/kg body weight once daily or 10 units once daily, whichever is more conservative. 1, 2

• The FDA-approved starting dose for insulin glargine in type 2 diabetes is 0.2 units/kg or up to 10 units once daily 2
• For patients with type 1 diabetes, approximately one-third of total daily insulin requirements should be given as basal insulin, with the remainder as short-acting premeal insulin 2
• Administer at the same time each day (any time of day, but consistency is critical) 2
• For patients with severe hyperglycemia (glucose ≥300-350 mg/dL or HbA1c ≥10-12%), consider starting at the higher end of the dosing range 1

Titration Schedule

Titrate basal insulin dose every 3 days based on fasting blood glucose, targeting 90-150 mg/dL (5.0-8.3 mmol/L) in most patients, or <100 mg/dL (<5.5 mmol/L) for more aggressive control. 1, 3

Specific Titration Algorithm:

• If 50% of fasting glucose values over the previous week are above target: Increase dose by 2 units 1, 3
• If >2 fasting glucose values per week are <80 mg/dL (<4.4 mmol/L): Decrease dose by 2 units 1, 3
• Alternative patient-managed approach: Increase by 2 units every 3 days until fasting glucose reaches target, provided no hypoglycemia occurs 4

The patient-managed titration approach achieves greater HbA1c reductions (-1.22% vs -1.08%) compared to clinic-managed titration, though with slightly higher hypoglycemia rates (33.3% vs 29.8%) 4

Insulin Selection: Glargine vs Detemir

Either glargine or detemir is acceptable for once-daily basal insulin therapy, though glargine typically requires lower total daily doses. 1

• Both analogues demonstrate similar efficacy in achieving glycemic targets (HbA1c reductions from 8.6% to ~7.1-7.2%) 5
• Detemir may require twice-daily dosing in 55% of patients to achieve adequate 24-hour coverage, whereas glargine is typically effective once daily 5
• When both are dosed once daily, detemir requires higher doses (0.52 units/kg) compared to glargine (0.44 units/kg) 5
• Detemir shows less weight gain (2.7 kg vs 3.5 kg) compared to glargine, particularly when once-daily dosing is maintained 5
• Both have similar hypoglycemia risk and demonstrate peakless, 24-hour duration of action in clinically relevant doses 6

Combination Therapy

Basal insulin should be combined with metformin and possibly one additional non-insulin agent. 1

• Continue metformin when initiating basal insulin unless contraindicated 1
• If basal insulin is titrated to appropriate fasting glucose but HbA1c remains above target, add either a GLP-1 receptor agonist or prandial insulin 1
• Sulfonylureas should typically be discontinued when advancing beyond basal insulin to more complex regimens 1

Critical Monitoring Points

Monitor fasting blood glucose daily during titration and assess for signs of overbasalization. 1, 3

• Signs of overbasalization include: basal dose >0.5 units/kg, bedtime-morning glucose differential ≥50 mg/dL, hypoglycemia, or high glucose variability 1
• If overbasalization occurs, reduce basal insulin and add prandial coverage or GLP-1 receptor agonist 1
• Increase monitoring frequency during any insulin regimen changes 2

Special Populations

For older adults, start at the lower end of the dosing range (0.1 units/kg) and use less aggressive titration targets (90-150 mg/dL fasting glucose). 1, 3

• Older adults have increased hypoglycemia risk and may require simplified regimens 1
• Consider reducing evening/pre-procedure basal insulin by 25% in perioperative settings 3

Administration Technique

Inject subcutaneously into the abdomen, thigh, or deltoid, rotating sites within the same region to prevent lipodystrophy. 2

• Never inject into areas of lipodystrophy or localized cutaneous amyloidosis, as this causes erratic absorption and hyperglycemia 2
• If switching injection sites from affected to unaffected areas, closely monitor for hypoglycemia 2
• Do not mix or dilute with other insulins 2
• Do not administer intravenously or via insulin pump 2

Switching Between Insulin Types

When switching from NPH to glargine once daily, use the same total daily dose; when switching from twice-daily NPH to once-daily glargine, use 80% of the total NPH dose. 2

• When switching from insulin glargine U-300 (Toujeo) to glargine U-100 (Lantus), use 80% of the U-300 dose 2
• Close monitoring is required during any insulin transition due to hypoglycemia risk 2