Comparative Analysis of the Advantages and Disadvantages of Nine Major Antidiabetic Drugs: A Comprehensive Overview for Clinical Application and Investment

01. Advantages and Disadvantages of Metformin

Metformin primarily lowers blood glucose by reducing insulin resistance, promoting glucose utilization in peripheral tissues, and inhibiting hepatic glucose output.

It is currently the first-line preferred glucose-lowering agent for the treatment of diabetes mellitus, and can be used either as monotherapy or as the foundational medication in various combination therapy regimens (such as the combination of insulin and oral hypoglycemic agents).

Advantages:

In addition to its effective glucose-lowering action, metformin can also reduce body weight, blood pressure, and lipid levels, exert cardioprotective effects, and significantly improve long-term prognosis, making it the first-line choice for overweight or obese patients with diabetes. It has a favorable safety profile and does not cause hypoglycemia when used as monotherapy. Furthermore, it is inexpensive and offers high cost-effectiveness.

Disadvantages:

Gastrointestinal reactions are common, and long-term use may affect vitamin B12 absorption. Contraindicated in patients with heart failure-induced hypoxia or severe hepatic and renal impairment to avoid lactic acidosis.

02. Advantages and Disadvantages of Sulfonylureas

Sulfonylurea hypoglycemic agents bind to sulfonylurea receptors on pancreatic β-cells, stimulating insulin secretion from the pancreas and increasing endogenous insulin levels to lower blood glucose. The presence of at least 30% normal β-cells in the islets of Langerhans is a prerequisite for their therapeutic effect.

Commonly used in clinical practice are gliquidone (Glurenorm), gliclazide (Diamicron), glibenclamide (Daonil), glipizide (Minidiab), and glimepiride (Amaryl).

Advantages:

With outstanding efficacy and low cost, it is a first-line medication for type 2 diabetes, having no adverse effects on the cardiovascular system and no cancer risk.

Disadvantages:

Hypoglycemia and weight gain are common adverse effects; individual patients may experience cutaneous allergic reactions, leukopenia, and other side effects. Secondary failure may occur during treatment. For elderly patients and those with mild to moderate renal impairment, short-acting sulfonylureas excreted via the biliary route are recommended, with gliquidone (Glurenorm) being more suitable.

03. Advantages and Disadvantages of Glinides

Glinides are a new generation of insulin secretagogues that bind to receptors on β-cells, closing ATP-dependent potassium channels in the β-cell membrane. This leads to β-cell depolarization, opening of calcium channels, and increased calcium influx, thereby inducing insulin secretion from β-cells.

Representative drugs include repaglinide (NovoNorm) and nateglinide (Starlix), which can be used in combination with other classes of oral hypoglycemic agents and basal insulin.

Advantages:

Its prominent advantage is the ability to mimic the physiological secretion of prandial insulin, effectively reducing postprandial hyperglycemia with a low risk of hypoglycemia and minimal impact on body weight, earning it the title of “prandial glucose regulator.”

It can still be used in patients with mild to moderate renal impairment.

Taken with meals, offering convenience and flexibility, resulting in good patient compliance; it is more suitable for patients with irregular meal patterns or elderly patients. When sulfonylureas fail, switching to glinides can still be effective.

Disadvantages:

Higher cost; improper use may also cause hypoglycemia.

04. Advantages and Disadvantages of α-Glucosidase Inhibitors

α-Glucosidase inhibitors inhibit the activity of α-glucosidases (involved in the degradation of disaccharides, oligosaccharides, and polysaccharides) in the intestine, thereby delaying the breakdown and absorption of glucose derived from carbohydrates.

This approach delays and reduces postprandial blood glucose elevation, making it particularly suitable for Chinese patients whose staple diet is carbohydrate-rich. It can be used in combination with dietary modifications, exercise, and other glucose-lowering medications.

Representative drugs include acarbose (Glucobay), which should be chewed with the first bite of staple food during meals.

Advantages:

Definite hypoglycemic effect, primarily acting locally in the gastrointestinal tract; only 2% is absorbed into the bloodstream, resulting in minimal systemic side effects on the liver and kidneys. It does not increase body weight and may even promote weight loss when used as monotherapy.

Does not cause hypoglycemia, provides cardiovascular protection, and is suitable for elderly diabetic patients and those with renal impairment.

It is also currently the only glucose-lowering drug, both domestically and internationally, with an approved indication for the treatment of IGT (impaired glucose tolerance, defined as a 2-hour postprandial blood glucose level between 7.8 and 11.0 mmol/L).

Disadvantages:

Because this class of drugs impedes the breakdown and absorption of carbohydrates in the intestine, prolonging their retention time, it leads to increased gas production from bacterial fermentation. Some patients experience initial symptoms when first using

Gastrointestinal reactions such as abdominal distension and increased flatulence.

Contraindicated in patients with gastrointestinal dysfunction, pregnant women, nursing mothers, and children.

Note: Concomitant use with other glucose-lowering drugs may cause hypoglycemia. If hypoglycemia occurs, it should be corrected with glucose; ingestion of starchy foods is ineffective.

05. Advantages and Disadvantages of Insulin Sensitizers

PPARγ Agonists (Peroxisome Proliferator-Activated Receptor γ) are present in the primary target tissues of insulin, such as the liver, adipose tissue, and skeletal muscle. Upon activation, PPARγ enhances insulin sensitivity in these target tissues through multiple pathways, thereby alleviating insulin resistance; its therapeutic effects require the presence of insulin.

These drugs belong to the thiazolidinedione class, with representative agents including rosiglitazone (Avandia, Tai Luo) and pioglitazone (Actos).

Advantages:

Does not stimulate insulin secretion but exerts its glucose-lowering effect by enhancing tissue sensitivity to insulin. This class of drugs is indicated for type 2 diabetes, impaired glucose tolerance, and metabolic syndrome, and can be used in combination with biguanides, sulfonylureas, or insulin to further improve glycemic control.

Monotherapy does not cause hypoglycemia.

Disadvantages:

Increases the risk of heart failure; contraindicated in patients with NYHA Class III or higher cardiac function. Use with caution in elderly patients aged 65 years and older.

Onset of action is slow; it may cause water and sodium retention, leading to edema and slight weight gain. Pioglitazone should be avoided in patients with bladder cancer or a history of bladder cancer.

06. Advantages and Disadvantages of GLP-1 Receptor Agonists

Glucagon-like peptide-1 (GLP-1) is an incretin hormone secreted by intestinal L cells.

GLP-1 acts on pancreatic β-cells in a glucose-dependent manner to increase insulin synthesis and secretion; increases the number of pancreatic β-cells; inhibits glucagon secretion; suppresses appetite and food intake; and delays gastric emptying.

GLP-1 is rapidly degraded and inactivated by dipeptidyl peptidase-4 (DPP-4) in vivo, limiting its clinical application.

GLP-1 Receptor Agonists: Analogs of GLP-1 that bind to and activate the GLP-1 receptor, exhibiting antihyperglycemic effects similar to those of GLP-1.

Currently, exenatide (Byetta) and liraglutide (Victoza) are marketed in China.

Advantages:

In addition to significantly lowering blood glucose levels, it also reduces body weight, lowers blood pressure, and improves β-cell function, demonstrating the potential to delay the progression of diabetes and reduce cardiovascular complications associated with diabetes. This combination of multiple pharmacological effects is not possessed by existing diabetes treatments.

Due to its glucose-dependent glucose-lowering mechanism that aligns with physiological needs, the risk of hypoglycemia is very low.

Disadvantages:

Short half-life. Gastrointestinal adverse reactions such as nausea and vomiting occur. The drug is expensive, requires injection, and is not recommended as a first-line treatment.

It cannot replace insulin in insulin-dependent patients. It is not indicated for the treatment of patients with type 1 diabetes mellitus or diabetic ketoacidosis.

07. Advantages and Disadvantages of DPP-4 Inhibitors

Dipeptidyl Peptidase-4 (DPP-4): GLP-1 is rapidly degraded by dipeptidyl peptidase-4 (DPP-4), resulting in loss of activity.

DPP-4 Inhibitors: These agents reduce the inactivation rate of incretin hormones (e.g., GLP-1), thereby increasing their plasma concentrations and reducing fasting and postprandial blood glucose levels in patients with type 2 diabetes in a glucose-dependent manner.

Currently available on the Chinese market are sitagliptin (Januvia), saxagliptin (Onglyza), vildagliptin (Galvus), and others.

Advantages:

Increases endogenous GLP-1 levels while improving dysfunction of pancreatic alpha and beta cells, offering advantages such as proven glucose-lowering efficacy, low risk of hypoglycemia, no weight gain, absence of gastrointestinal adverse reactions, and high safety and tolerability.

Oral administration, requiring only once-daily dosing, ensures good patient compliance.

Disadvantages:

DPP-4 is a pleiotropic enzyme, and its inhibitors may also prolong the effects of hormones such as ghrelin, neuropeptide Y, and substance P, potentially leading to adverse reactions including neurogenic inflammation, elevated blood pressure, and triggering immune responses. These agents are relatively expensive and are not yet covered by medical insurance in China.

08. Advantages and Disadvantages of SGLT-2 Inhibitors

SGLT-2 (Sodium-Glucose Cotransporter-2): The kidneys filter 160–180 g of glucose daily, and nearly all of this glucose is reabsorbed back into the bloodstream. SGLT-2 is the primary transporter involved in this process and represents a novel therapeutic target for diabetes.

SGLT-2 Inhibitors: Primarily lower blood glucose by inhibiting SGLT-2 activity, reducing renal glucose reabsorption, and increasing urinary glucose excretion. Dapagliflozin is currently available on international markets.

Advantages:

SGLT2 inhibitors rarely cause hypoglycemia and offer benefits in improving body weight and blood pressure. They are administered as once-daily oral tablets, ensuring good adherence.

Disadvantages:

It may be associated with nasopharyngitis, fungal infections, and genitourinary tract infections; the long-term safety of medication requires further observation.

09. Advantages and Disadvantages of Insulin and Its Analogs

Rapid-acting: insulin lispro, insulin aspart;

Short-acting: Regular insulin;

Intermediate-acting: protamine zinc insulin, neutral protamine Hagedorn (NPH) insulin;

Long-acting: Protamine Zinc Insulin, Insulin Glargine.

Novolin R: A short-acting insulin preparation that can be used in combination with intermediate- or long-acting insulin preparations.

Novolin N: Isophane insulin suspension (NPH), an intermediate-acting insulin preparation.

Novolin 30R: A biphasic insulin preparation containing 30% soluble neutral insulin and 70% isophane zinc insulin suspension.

Advantages:

Insulin and insulin analogs are the most potent agents for glycemic control to date, with no adverse effects on the liver or kidneys. All patients with diabetes who are not suitable for oral hypoglycemic agents (such as those with type 1 diabetes, pregnant women, diabetic ketoacidosis, or hepatic and renal insufficiency) can be switched to insulin therapy.

Early use of insulin can also help protect and restore the function of pancreatic β-cells.

Disadvantages:

The risk of hypoglycemia is relatively high, which may lead to weight gain. In some patients, skin allergies or lipoatrophy occur at the injection site. Injection administration causes inconvenience for patients, and insulin analogs are relatively expensive.

Original Title: A Comprehensive Comparison of the Pros and Cons of 9 Glucose-Lowering Drugs—Master Them All at Once!