| abstract |
The present invention provides a prolonged-release liquid type of pharmaceutical preparation prepared by coating a pharmaceutically active drug-ion exchange resin complex which was treated previously with an impregnating agent, with a water permeable diffusion barrier material, followed by suspending the coated complex in a solution containing preservatives. n The formulation of the present invention does not develop the rupture of the diffusion barrier film even in a solution containing preservatives. Therefore the formulation of the present invention is a prolonged-release liquid type of pharmaceutical preparation which is stable and does not lose the controlled release of the active ingredient. |