The ingestion of drug products with alcohol can have an adverse effect on drug levels in a patient's blood. The Food and Drug Agency (FDA) issued an alert in 2005 after hydromorphone was withdrawn from the market after clinical trials showed ingestion with alcohol to potentially result in lethal drug peak plasma concentrations. The potential impact of alcohol on extended release (ER) tablet matrices and the need to develop ER matrices robust to alcohol effects has then been of interest. This study investigated the compaction properties of polyols and their effect on drug release. Polyols (erythritol, xylitol, mannitol and maltitol) with increasing hydroxyl groups were used as diluents for HPMC matrices containing theophylline. Release profiles were determined in pH 1.2 and 6.8 dissolution media with hydro-alcoholic concentrations of 5-40%. Increases in the polyols' hydroxyl groups brought about an increase in tablet strength and a decrease in the drug release rates. This is likely due to stronger bond formation with increasing hydroxyls. The impact of alcohol on drug release was studied further for maltitol formulations. Maltitol was resilient to the presence of ethanol (5-40% v/v) at pH 1.2 (f2=57-74) but not at pH 6.8 (f2=36-48). Drug release was not different above 5% alcohol concentration at pH 6.8. The results of this in vitro study suggest that ethanol concentrations as high as 40% do not substantially alter the drug release properties of theophylline from maltitol matrix tablets. However, care and consideration should be given to the choice of polyol or mixture of polyols in obtaining a desired drug release profile.