Skin-friendly plasters for the transdermal administration of non-steroidal antirheumatic agents

Controlled release plaster for non-steroidal anti-rheumatic agents has a sticky matrix comprising: (1) 25-90 wt% polyisobutylene-based synthetic matrix polymers; (2) 5-40 wt% amorphous poly- alpha -olefin; (3) 10-60 wt% insoluble, hydrophilic filler with an average particle size below 100 microns; and (4) 0.001-20 wt% medicinal agent. Matrix plaster with a flexible outer layer and a water-insoluble, sticky matrix containing an active ingredient, designed for the controlled release of non-steroidal anti-rheumatic agents onto the skin, in which the matrix is free from mineral oils and adhesive resins and comprises: (1) 25-90 wt% synthetic matrix polymers based on polyisobutylene (PIB); (2) 5-40 wt% amorphous poly- alpha -olefin; (3) 10-60 wt% insoluble, hydrophilic filler with an average particle size (d50) of less than 100 microns; and (4) 0.001-20 wt% medicinal agent. An Independent claim is also included for a method for the production of this plaster by homogenising all the matrix components together in the melt without adding solvent.