Introduction to Biguanide Antidiabetic Drugs

1.Mechanism of Action of Introduction to Biguanide Antidiabetic Drugs:

The detailed mechanism of action of biguanide drugs is still not fully understood, but possible mechanisms include:

1. Inhibition of appetite and absorption of glucose in the intestines. They can also inhibit the absorption of amino acids, fats, cholesterol, bile salts, sodium, and water in the intestinal wall, making them useful for weight loss. However, this effect is not present when administered intravenously.
2. Increased utilization of glucose by peripheral tissues and promotion of anaerobic glycolysis in cells, but it may lead to excessive lactate production.
3. No stimulation of insulin secretion, but they can enhance the binding of insulin to its receptors, especially improving post-receptor effects, thereby promoting glucose utilization.
4. Lipid-lowering effect, which can reduce cholesterol and triglycerides, beneficial for the prevention and treatment of atherosclerosis.

2.Types of Biguanide Antidiabetic Drugs:

Currently, there are two types of biguanide drugs that have been developed and used: (1) Metformin. (2) Phenformin.

3.Glycemic Lowering Effect of Biguanide Antidiabetic Drugs:

Moderate intensity. Similar to sulfonylurea drugs, the glycemic lowering effect of each tablet of biguanide drugs is comparable. However, when calculated per milligram of the drug, there is a difference in the glycemic lowering effect, with phenformin being stronger than metformin. Based on the aforementioned mechanism of action, biguanide drugs themselves do not cause hypoglycemia, but when used in combination with sulfonylurea drugs or insulin, they can cause hypoglycemia.

4.Indications and Contraindications:

1. Indications: First-line treatment for type 2 obese patients with inadequate response to diet and exercise; when monotherapy with sulfonylurea drugs is ineffective or leads to primary or secondary failure, switching to or combining with biguanide drugs is recommended; for type 1 patients with large fluctuations in blood glucose or high insulin requirements, or suspected insulin resistance, adding biguanide drugs may be considered.
2. Contraindications: Acute complications such as diabetic ketoacidosis, impaired liver or kidney function, pregnancy, and childbirth; severe stress conditions such as surgery, trauma, infection, etc., should be treated with insulin instead.