The present invention provides a stable solid pharmaceutical composition for oral administration of antimuscarnic agents and processes for preparation thereof. Typically, the present invention relates to pharmaceutical compositions of Tolterodine, its pharmaceutically acceptable salt and processes for preparation thereof. The controlled-release composition comprises (i) an inert core (ii) a first layer disposed on the inert core, wherein the first layer comprises tolterodine or a pharmaceutically acceptable salt thereof, a water insoluble polymer and a water soluble polymer (iii) a second layer disposed on the first layer, wherein the second layer comprises tolterodine and a binder and (iv) a third layer disposed on the second layer, wherein the third layer comprises a water insoluble polymer, and a pore-forming agent.
