The mechanical stress of the grinding action of the stomach in the fed state could introduce variability if an extended release tablet containing metformin hydrochloride is broken down more rapidly than anticipated. Because food prolongs the gastric retention time, extended release formulations administered with food are exposed to longer duration of mechanical stress in the stomach. The latter raises the possibility of increased release rate (than intended) of the drug from the formulation. This can result in a higher risk of 'dose dumping', creating a potential safety risk for patients. Therefore it is clinically important to assess the effect of food on extended release formulations of metformin hydrochloride and metformin hydrochloride/glimepiride.