Acta Pharm. 54 (2004) 301-317

Design and in vitro evaluation of new drug-in-adhesive formulations of
fentanyl transdermal patches

AMIR MEHDIZADEH,^1,2 TAYEBE TOLIATE,¹ MOHAMMAD REZA ROUINI,^1*
SHARYAR ABASHZADEH² and FARID DORKOOSH¹² 

rouini@sina.ac.ir.com

¹Tehran University of Medical Sciences, Faculty of Pharmacy, Tehran, Iran
²Hakim Pharmaceutical Company, Tehran, Iran

The present research was designed to evaluate different matrix, drug-in-adhesive and reservoir formulations of fentanyl transdermal patches. The target was to design drug-in-adhesive patches (DIAPs); a full factorial design was used. Different types and amounts of liquid, pressure-sensitive adhesives (PSAs) were used and evaluated with respect to drug release and adhesive properties. A very simple but precise method, the simplified peel 180° test, was developed to measure and compare adhesive properties of transdermal patches. The results showed that release kinetics obeyed the square root of time or Higuchi model, indicating the diffusion controlled release mechanism. It was found that the amount of fentanyl needed for each 10 cm² three-days DIAP should be 3.3 mg. The respective amounts for reservoir and matrix patches were 2.5 and 5 mg. It was concluded that acrylic PSAs showed the best adhesion and release properties.

Keywords: fentanyl, transdermal drug delivery systems, patches, drug release