Formulation study of oxybutynin patches

Pharm Dev Technol. 2007;12(3):239-46. doi: 10.1080/10837450701212701.


The present feasibility study was designed to obtain a monolayer patch containing oxybutynin (OXY) avoiding chemical permeation enhancers. The highest flux was obtained with a polydimethylsiloxane matrix patch. Because OXY crystals were detected in the matrix within a week, two amino methylmethacrylate copolymers (Eudragit E or Eudragit RS) were used as OXY crystallization inhibitors. A preliminary in vivo study indicated that flux from the stabilized patches had to be increased about 30-40%. This goal was reached by occlusion with a polyethylene layer.

Publication types

  • Clinical Trial

MeSH terms

  • Calorimetry, Differential Scanning
  • Drug Compounding
  • Feasibility Studies
  • Female
  • Humans
  • In Vitro Techniques
  • Mandelic Acids / analysis
  • Mandelic Acids / pharmacokinetics*
  • Mandelic Acids / pharmacology
  • Muscarinic Antagonists / analysis
  • Muscarinic Antagonists / pharmacokinetics*
  • Muscarinic Antagonists / pharmacology
  • Permeability / drug effects
  • Skin / drug effects
  • Spectroscopy, Fourier Transform Infrared


  • Mandelic Acids
  • Muscarinic Antagonists
  • oxybutynin