Pioglitazone hydrochloride is an oral antidiabetic agent that acts primarily by decreasing insulin resistance.

Pioglitazone [(±)-5-[[4-[2-(5-ethyl-2-pyridinyl)ethoxy]phenyl]methyl]-2,4-] thiazolidinedione mono-hydrochloride belongs to a different chemical class and has a different pharmacological action than the sulfonylureas, metformin, or the a-glucosidase inhibitors. The molecule contains one asymmetric carbon, and the compound is synthesized and used as the racemic mixture. The two enantiomers of pioglitazone inter-convert in vivo. No differences were found in the pharmacologic activity between the two enantiomers.

Pioglitazone hydrochloride is an odorless white crystalline powder that has a molecular formula of C19H20N2O3S•HCl and a molecular weight of 392.90 daltons. It is soluble in N,N-dimethylformamide, slightly soluble in anhydrous ethanol, very slightly soluble in acetone and acetonitrile, practically insoluble in water, and insoluble in ether.