creation date: 2025-11-28 09:17
tags: Pharmacology
Insulin
Background
Insulin is a peptide hormone secreted by the pancreas (beta cells). Use of exogenous insulin is indicated when there is inadequate production of endogenous insulin.
Insulin binds to insulin receptors on the plasma membranes throughout the body. Generally, insulin activity causes the translocation of glucose transporters to the membrane resulting in the influx of glucose from the blood into the cell.
Additionally, insulin causes the following effect depending on the cell type:
- Hepatic cells: promotes glycogenesis, inhibits gluconeogenesis
- Adipocytes: promotes lipogenesis, inhibits lipolysis
- Muscle cells: promotes glycogenesis and protein synthesis, inhibits protein catabolism
- Pancreatic beta cells: inhibits glucagon release
- Brain cells: involved in appetite regulation
Types
Rapid-Acting
Characteristics
- Peak: 1 hr
- Duration: 3-4 hrs
Use
- Pre-prandial bolus
Examples
- Insulin aspart (Fiasp, NovoLog)
- Insulin glulisine (Apidra)
- Insulin lispro (Ademelog, Humalog, Lyumjev)
Short-Acting
Characteristics
- Peak: 2-3 hrs
- Duration: 4-6 hrs
Use
- Pre-prandial bolus
Examples
- Regular insulin (IV)
Intermediate-Acting
Characteristics
- Peak: 6-10 hrs
- Duration: 10-16 hrs
Use
- Basal insulin (BID)
Examples
- NPH
Long-Acting
Characteristics
- Peak: none
- Duration: 24 hrs
Use
- Basal insulin (once daily PM post-prandial)
Examples
- Insulin glargine (Lantus)
- Insulin detemir (Levemir)
Ultralong-Acting
Characteristics
- Peak: none
- Duration: 36+ hrs
Use
- Basal insulin
Examples
- Insulin icodec (Awiqli) - once weekly