POLYAMINE DRUG-RESIN COMPLEXES
Disclosed are oral pharmaceutical preparations which comprise a pharmacologically-active polyamine drug bound to a cation-exchange resin to provide a drug-resin complex having a drug content greater than one equivalent of amine per equivalent of cation-exchange capacity. The drug-resin complex is optionally coated with a water-permeable diffusion barrier coating that is insoluble in gastrointestinal fluids thereby providing a controllable release of drug under conditions encountered in the gastrointestinal tract.