Design and Evaluation of Transdermal Patches of Labetalol Hydrochloride

Abstract

Introduction: β-blockers like labetalol hydrochloride (LHCl) are potent and highly effective antihypertensive
agents. The main drawback associated with β-blockers is extensive first-pass metabolism, variable bioavailability
requiring frequent dose administration. This makes them an ideal candidate for transdermal therapeutic
systems. β-blockers formulated as transdermal therapeutic system should enhance the bioavailability as well as
improve patient compliance. Constant innovations and improvement in this field have potential that largeâ€scale
commercialization of transdermal dosage forms can be done. Aim: The aim of the present work was to develop and
evaluate matrix type transdermal patches containing new polymeric combination to enhance the bioavailability
as well as improve patient compliance. Materials and Methods: In present work development and evaluation of
matrix-type transdermal patches containing a new polymeric combination of HPMC, carbopol934, ethyl cellulose,
propylene glycol, polyethylene glycol, and isopropyl myristate for labetalol (LHCl) HCl (LBHCl). Film casting
technique has been used in preparing patches. The patches were characterized for physical, in vitro release studies
and ex vivo permeation studies using human cadaver skin. Result: F6

was found to be better than the other
formulations and hence selected as the optimized formulation on the basis of results of evaluating parameters such
as thickness, flatness, folding endurance, tensile strength, moisture content, moisture uptake, and drug content,
formulation. The optimized patch was assessed for its pharmacokinetic, pharmacodynamic, skin irritation test and
stability studies. Conclusion: Successful development of sustained release matrix type of transdermal patches
which can show greater patient compliance in treating hypertension has been done.