What are the types of basal insulin?

Types of Basal Insulin

Basal insulin options include NPH insulin, long-acting insulin analogs (insulin glargine U-100/U-300, insulin detemir, and insulin degludec), and continuous delivery of rapid-acting insulin via an insulin pump. 1

Long-Acting Insulin Analogs

Insulin Glargine

• U-100 Glargine: First long-acting insulin analog available (since 2000) 2
• U-300 Glargine: More concentrated formulation with:
  • Longer duration of action than U-100 glargine
  • More stable 24-hour glucose-lowering profile
  • Lower risk of nocturnal hypoglycemia
  • Slightly lower efficacy per unit compared to U-100 formulations 1, 3

Insulin Detemir

• Introduced in 2005 2
• May require twice-daily dosing in some patients 3
• Demonstrates less variable absorption compared to NPH insulin
• Associated with less weight gain compared to other basal insulins 4

Insulin Degludec

• Available in U-100 and U-200 formulations
• Longest half-life among basal insulins
• Most stable pharmacokinetic profile
• Can be administered at any time of day (but should be consistent) 3, 2

Intermediate-Acting Insulin

NPH (Neutral Protamine Hagedorn) Insulin

• Traditional intermediate-acting insulin
• Has pronounced peak in action (unlike long-acting analogs)
• Higher risk of hypoglycemia, especially nocturnal hypoglycemia
• More variable absorption profile compared to long-acting analogs 5, 4

Clinical Considerations

Advantages of Long-Acting Analogs over NPH

1. Reduced risk of symptomatic and nocturnal hypoglycemia 1
2. More consistent 24-hour coverage with less pronounced peaks 3
3. Lower day-to-day glucose variability 5
4. Better fasting glucose control 6

Starting Doses and Titration

• Initial dose typically 0.1-0.2 units/kg/day based on body weight and degree of hyperglycemia 1
• Titrate over days to weeks as needed based on fasting glucose readings 3
• Watch for overbasalization signals:
  • Basal dose >0.5 units/kg
  • High bedtime-morning glucose differential
  • Hypoglycemia episodes
  • High glucose variability 1

Clinical Application

• Basal insulin can be added to metformin and other oral agents or non-insulin injectables 1
• For patients with type 1 diabetes, basal insulin is used in combination with mealtime insulin 1
• For patients with type 2 diabetes where oral agents are failing, basal insulin can be added 6

Switching Between Basal Insulins

• When switching from insulin glargine to insulin degludec, the initial dose can generally remain the same 3
• Consider 10-20% dose reduction when switching to U-300 glargine or from degludec to U-300 glargine in patients at high risk for hypoglycemia 3

Important Precautions

• Do not mix insulin glargine with other insulins in the same syringe 3
• Store according to manufacturer recommendations 3
• Monitor closely during transition periods between different basal insulins 3