The invention relates to a novel pharmaceutical sustained release formulation of guaifenesin. The formulation may comprise a hydrophilic polymer, preferably a hydroxypropyl methylcellulose, and a water-insoluble polymer, preferably an acrylic resin, in a ratio range of about one-to-one (1:1) to about...http://www.google.com.au/patents/US7838032?utm_source=gb-gplus-sharePatent US7838032 - Sustained release of guaifenesin
