An aqueous liquid suspension containing a coated drug-ion exchange resin complex comprising a core composed of an amphetamine complexed with a pharmaceutically acceptable ion-exchange resin and an uncoated amphetamine-ion exchange resin complex is provided. The coated amphetamine-ion exchange resin complex is in admixture with a polymer to form a matrix. The coating is a polyvinyl acetate polymer and a plasticizer. Methods of making the coated complex and the liquid suspension are described.
