Insulin types are generally classified by how long they take to begin action, peak, and last. The five basic types are: rapid-acting, short-acting, intermediate-acting, mixed, and long-acting.
Rapid-acting insulin
As the name implies, rapid-acting insulin lowers blood sugar quickly, as insulin from the pancreas does. It is usually taken at the start of a meal. When taken at dinner time, rapid-acting insulin can prevent severe drops in blood sugar (hypoglycemia) during the night. Some often-prescribed rapid-acting insulins are:
- NovoRapid (insulin aspart) begins to work in 9 to 20 minutes, and peaks in 1.0 to 1.5 hours. Its effect lasts from 3.0 to 5.0 hours.
- Fiasp (faster-acting insulin aspart) begins to work in 4 minutes, and peaks in 0.5 to 1.5 hours. Its effect lasts from 3.0 to 5.0 hours.
- Apidra (insulin glulisine) begins to work in 10 to 15 minutes and peaks in 1.0 to 1.5 hours. Its effect lasts 3.5 to 5.0 hours.
- Humalog (insulin lispro) begins to work in 10 to 15 minutes and peaks in 1.0 to 2.0 hours. Its effect lasts 3.0 to 4.75 hours.
Short-acting insulin (regular)
- Regular insulin (Humulin R and Novolin R) begin to work in 30 to 60 minutes and peaks between 2 and 4 hours, lasting 6 to 8 hours.
- U500 (regular with 5x concentration) begins to work in 30 minutes and peaks in 30 minutes, lasting 18 to 24 hours.
Intermediate-acting insulin
NPH insulin begins working in 1 to 2 hours, peaks in 4 to 12 hours, and lasts 14 to 24 hours.
Long-acting insulin
- Basaglar (insulin glargine) goes to work in 1 to 1.5 hours, maintains a steady level, and lasts for 11 to 24 hours.
- Levemir (insulin detemir) goes to work in 1 to 2 hours, maintains a steady level, and lasts for as long as 24 hours.
- Tresiba (insulin degludec) goes to work in 30 to 90 minutes, maintains a steady level, and lasts 42 hours.
Mixed insulin
Humulin 70/30 goes to work in 30 minutes, peaks at 2 to 4 hours, and lasts 14 to 24 hours.
Novolin 70/30 goes to work in 30 minutes, peaks in 2 to 12 hours, and lasts as long as 24 hours.
Novolog 70/30 goes to work in 10 to 20 minutes, peaks in 1 to 4 hours, and lasts as long as 24 hours.
Humulin 50/50 goes to work in 30 minutes, peaks at 2 to 5 hours, and lasts 18 to 24 hours.
Humalog mix 75/25 goes to work in 15 minutes, peaks in 30 minutes to 2.5 hours, and lasts 16 to 20 hours.