Developing sustained-release matrix tablets of ramosetron HCl was the major goal of the current effort. A Ramosetron HCl formulation with a once-each-day sustained release is preferred to lower the frequency of administration and increase patient compliance. Such sustained release KCarrageenan and Chitosan were chosen as the two distinct polymers used to develop the matrix tablet of Ramosetron HCl. After determining the appropriate ratio of the drug to the polymer to regulate drug release up to the specified time, the release rates were regulated by a single polymer and a combination of two polymers with varied rate-controlling capabilities. The IR investigation found no indication of a chemical interaction between the additives and the drug. The wet granulation process was used to obtain the granules.