What are the oral antidiabetic drugs (Diabetes Mellitus) approved for the treatment of Type 2 Diabetes Mellitus (Type 2 DM)?

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From the Guidelines

Oral antidiabetic drugs approved for the treatment of type 2 diabetes mellitus include metformin, sulfonylureas, thiazolidinediones, DPP-4 inhibitors, and SGLT-2 inhibitors, with metformin being the recommended first-line therapy due to its effectiveness and safety profile 1.

Medication Classes

  • Biguanides: metformin (starting at 500mg daily, increasing to 1000-2000mg daily in divided doses) is the primary medication in this class, effective in reducing hepatic glucose production and improving insulin sensitivity without causing weight gain or hypoglycemia.
  • Sulfonylureas: glipizide (5-20mg daily), glimepiride (1-8mg daily), and glyburide (1.25-20mg daily) stimulate insulin secretion from pancreatic beta cells.
  • DPP-4 inhibitors: sitagliptin (100mg daily), saxagliptin (2.5-5mg daily), and linagliptin (5mg daily) prevent the breakdown of incretin hormones, enhancing insulin secretion and reducing glucagon.
  • SGLT-2 inhibitors: empagliflozin (10-25mg daily), dapagliflozin (5-10mg daily), and canagliflozin (100-300mg daily) reduce glucose reabsorption in the kidneys, promoting urinary glucose excretion.
  • Thiazolidinediones: pioglitazone (15-45mg daily) improves insulin sensitivity in peripheral tissues.

Treatment Selection

Treatment selection should be individualized based on efficacy, side effect profile, comorbidities, cost, and patient preferences, often requiring combination therapy as the disease progresses 1.

Recommendation

The American College of Physicians recommends that clinicians prescribe metformin to patients with type 2 diabetes when pharmacologic therapy is needed to improve glycemic control, due to its strong evidence and moderate-quality evidence 1. When a second oral therapy is considered, clinicians should consider adding either a sulfonylurea, a thiazolidinedione, an SGLT-2 inhibitor, or a DPP-4 inhibitor to metformin to improve glycemic control, with a weak recommendation and moderate-quality evidence 1.

From the FDA Drug Label

ACTOS (pioglitazone hydrochloride) is an oral antidiabetic agent that acts primarily by decreasing insulin resistance. ACTOS is used in the management of type 2 diabetes mellitus

  • Oral antidiabetic drugs approved for the treatment of type 2 DM include:
    • Pioglitazone (PO) 2 Note: The information for glimepiride (PO) 3 does not explicitly state its approval for the treatment of type 2 DM.

From the Research

Oral Antidiabetic Drugs

Oral antidiabetic drugs play a crucial role in the management of type 2 diabetes mellitus (T2DM). The following are some of the oral antidiabetic drugs approved for the treatment of T2DM:

  • Metformin: a biguanide that is commonly used as the first-line treatment for T2DM 4, 5
  • Pioglitazone: a thiazolidinedione that can be used in combination with metformin, sulfonylureas, or other antidiabetic medications 6
  • Sulfonylureas: a class of drugs that can be used as second-line treatment for T2DM, especially in patients who have failed to respond to metformin 7
  • Sodium-glucose cotransporter 2 (SGLT2) inhibitors: a class of drugs that are recommended for patients with atherosclerotic cardiovascular disease, heart failure, or kidney disease 8
  • Glucagon-like peptide 1 (GLP1) receptor agonists: a class of drugs that are recommended for patients with atherosclerotic cardiovascular disease 8
  • Dipeptidyl peptidase 4 (DPP4) inhibitors: a class of drugs that are generally well-tolerated but should be used with caution in patients with risk factors for heart failure 8

Mechanism of Action

These oral antidiabetic drugs work through different mechanisms to lower blood glucose levels, including:

  • Reducing glucose production in the liver (metformin) 4
  • Increasing insulin sensitivity (pioglitazone) 6
  • Stimulating insulin release from the pancreas (sulfonylureas) 7
  • Inhibiting glucose reabsorption in the kidneys (SGLT2 inhibitors) 8
  • Enhancing glucose-dependent insulin secretion (GLP1 receptor agonists) 8
  • Inhibiting the breakdown of incretin hormones (DPP4 inhibitors) 8

Clinical Use

The choice of oral antidiabetic drug depends on various factors, including the patient's clinical profile, comorbidities, and glycemic control. Clinicians should be aware of the pharmacological characteristics of each class of medication and their effects on cardiovascular health and renal function, balanced by potential adverse effects 8, 5.

References

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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