Description

Glipizide is an oral medication for type 2 diabetes. It belongs to the class of drugs known as sulfonylureas. It works by directly stimulating the pancreas to produce and release insulin.

Indications

Glipizide is primarily indicated for the management of type 2 diabetes mellitus. It is used as an adjunct to diet and exercise to improve blood glucose control in adults with type 2 diabetes.

Mechanism of Action

Glipizide’s mechanism of action is focused on the pancreas and is independent of the body’s insulin sensitivity.

1. Pancreatic Beta-Cell Stimulation: Glipizide binds to a specific receptor on the surface of pancreatic beta-cells. This receptor is part of an ATP-sensitive potassium (KATP​) channel.
2. Channel Closure: The binding of glipizide to this receptor closes the potassium channel.

3. Membrane Depolarization: The closure of the potassium channel prevents potassium ions from flowing out of the cell, which leads to a buildup of positive charge inside the cell. This causes the cell membrane to depolarize.

4. Calcium Influx and Insulin Release: The depolarization opens nearby voltage-gated calcium channels. Calcium ions then rush into the beta-cell. The influx of calcium is the signal that triggers the fusion of insulin-containing vesicles with the cell membrane, leading to the rapid release of insulin into the bloodstream.

In essence, glipizide works by forcing the pancreas to release more insulin, which in turn lowers blood glucose levels. This mechanism makes glipizide effective but also carries a risk of hypoglycemia (low blood sugar), as the insulin release is not dependent on current glucose levels.