[Use of poly(meth)acrylates for the control and release of pholedrine sulfate from microdragees]

Pellets with pholedrine sulphate are coated by means of a fluid-bed process with six different poly(meth)acrylate coating materials. The coatings showed drug release widely different. A wide pH-independent release showed film-coated pellets with Eudragit RS, RL and E 30D as coating material. By application of Scopacryl D 336, D 339 and D 340 the acceleration of liberation by the pH-value of 7,4 is related to the increasing amount of acrylic acid in polymer. The rate of release can be controlled by mixing coatings with different permeability in wide range. Diagram of logarithm permeability coefficient against the mixing proportion can be used for selection a coating composition with wished permeability.