Development and Evaluation of Transdermal Films of Oxybutynin

Oxybutynin is an anticholinergic drug used to treat over active bladder (OAB) which is a chronic and distressing medical condition symptomatised by urinary urgency and frequency and an urge to urinate immediately with or without urinary incontinence. In our present investigation an attempt has been made to formulate transdermal films of Oxybutynin using Hydroxy Propyl Methyl Cellulose (HPMC) and Carbopol 934-P alone and in combination with different ratios along with Propylene Glycol (PG) which can serve as plasticizer cum permeation enhancer. The films were prepared by solvent casting technique. They are evaluated for physical appearance, drug content, thickness, tensile strength, percent elongation, folding endurance, water vapour transmission rate (WVTR) and in vitro drug release through rat abdominal skin using Franz diffusion cell. It was found that HPMC and Carbopol 934- P have good film forming properties. Between the two polymers used results showed that the formulation HC35 was very flexible with highest folding endurance. The drug release for all the formulations, it has been observed that transdermal films of Carbopol 934- P alone i.e. C3 and C2 and HPMC: Carbopol 934- P (1:3) i.e. HC30 and HC 29 shown more than 88% release, which have the best release pattern among all the formulations prepared. Further it was noticed that as the concentration of PG increases the release pattern also increases. In conclusion combination and HPMC and Carbopol 934- P with PG can potentially be optimized to develop and effective transdermal drug delivery system for Oxybutynin.