pioglitazone

Pioglitazone is an oral thiazolidinedione antidiabetic agent used to improve glycemic control in adults with type 2 diabetes. It is a selective agonist of peroxisome proliferator-activated receptor gamma (PPAR-γ), increasing insulin sensitivity in liver, muscle, and adipose tissue. By modulating gene transcription, pioglitazone lowers hepatic glucose output and enhances peripheral glucose uptake when combined with diet and exercise. It is available under brand names such as Actos and in generic forms, and is used alone or with other agents including metformin, sulfonylureas, or insulin.

Typical starting dose is 15 mg once daily, titrating to 30 mg or 45 mg as tolerated and needed for glycemic control. It can be used as monotherapy or in combination therapy.

Pioglitazone is well absorbed and undergoes hepatic metabolism, mainly by CYP2C8 and to a lesser extent by CYP3A4, with active metabolites contributing to effect. It has a variable half-life and is excreted in urine and feces.

Common adverse effects include weight gain, edema, headache, and upper respiratory infections. It may cause fluid retention and can worsen or precipitate heart failure; it is contraindicated in symptomatic heart failure and in active liver disease. Liver injury potential warrants periodic monitoring of liver enzymes. Some studies have linked long-term use with an increased risk of bladder cancer. Caution is advised in elderly patients and those with osteoporosis or fracture risk. It is not recommended during pregnancy.

Pioglitazone may interact with other antidiabetic agents and with drugs affecting CYP2C8 or CYP3A4. Baseline assessment and ongoing monitoring of liver function and cardiovascular status are advised during therapy.