Hydrogel discs of poly(vinyl alcohol) loaded with glipizide, an oral antidiabetic drug, were prepared with glutaraldehyde (GA) as a crosslinker. Various formulations were prepared with various amounts of polymer, GA, and initial drug. The prepared hydrogel discs were characterized by thermogravimetric analysis, differential scanning calorimetric analysis, and X-ray diffractometry. The dynamic swelling behavior and drug-release patterns were dependent on the crosslink density. The hydrogel discs were capable of releasing drug for up to 24 h. The discs that were prepared with a higher concentration of GA released the drug more slowly. The release data were fitted to an empirical equation to determine the transport mechanism, which indicated a non-Fickian trend for drug transport. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 116:1732-1738, 2010