There are several types of insulin, classified based on their onset of action, peak effect, and duration of action. Insulin is categorized into four main types: rapid-acting, short-acting, intermediate-acting, and long-acting. Additionally, there are premixed insulins that combine two types of insulin. Here’s an overview of each type:

1. Rapid-Acting Insulin:
   • Examples: Insulin lispro (Humalog), insulin aspart (NovoLog), insulin glulisine (Apidra).
   • Onset: 15 minutes.
   • Peak: 1-2 hours.
   • Duration: 3-4 hours.
   • Administration: Given just before or immediately after meals to control postprandial glucose spikes.
2. Short-Acting Insulin:
   • Example: Regular insulin (R insulin, Humulin R, Novolin R).
   • Onset: 30 minutes to 1 hour.
   • Peak: 2-3 hours.
   • Duration: 3-6 hours.
   • Administration: Typically taken 30 minutes before meals to cover glucose rise after eating.
3. Intermediate-Acting Insulin:
   • Examples: NPH insulin (Neutral Protamine Hagedorn), insulin isophane.
   • Onset: 1-2 hours.
   • Peak: 4-12 hours (can vary widely between individuals).
   • Duration: Up to 18 hours.
   • Administration: Usually given twice a day, often in the morning and evening, to provide coverage for a longer duration.
4. Long-Acting Insulin:
   • Examples: Insulin glargine (Lantus, Basaglar), insulin detemir (Levemir), insulin degludec (Tresiba).
   • Onset: Varies (generally within 1-2 hours for glargine and detemir).
   • Peak: Minimal peak effect.
   • Duration: Up to 24 hours.
   • Administration: Typically administered once daily, although some long-acting insulins may be taken twice daily.
5. Premixed Insulin:
   • Examples: Various combinations, such as 70/30 (70% NPH and 30% regular insulin) or 75/25 (75% insulin lispro protamine suspension and 25% insulin lispro).
   • Onset, Peak, and Duration: Varies based on the specific combination.
   • Administration: Usually taken before meals, with the goal of providing both short- and intermediate-acting insulin coverage.

It’s important to note that insulin regimens are highly individualized, and the choice of insulin type and regimen is based on factors such as lifestyle, eating habits, blood glucose levels, and individual response to insulin. Your healthcare team will work with you to determine the most suitable insulin therapy plan for your needs. Always consult with your healthcare provider for personalized advice and adjustments to your insulin regimen.