Pharmaceutical compositions endowed with sequestering activity for the biliary acids, containing colestyramin as their active principle, and process for preparing them

A pharmaceutical composition for oral administration at improved and reduced therapeutically efficacious dosage levels of cholestyramine said composition possessing sequestering activity of the biliary acids, and comprising colestyramin particles around each of said particles is a homogeneous dispersion of an antimicrobial agent and a suspending or coating agent, said antimicrobial agent being present in an amount ranging from 0.001 to 0.05 gram per gram of colestyramin and said suspending or coating agent being present in an amount ranging from 0.01 to 10 grams per gram of colestyramin.