Objective: The study involved development of transdermal delivery system (TDDS) of doxazosinmesylate (doxa) to achieve effective systemic delivery of the drug.Methods: TDDS of doxa was prepared using hydroxypropyl methyl cellulose (HPMC) K100LV and polyvinyl pyrrolidone (PVP) K30 in 3:1 ratio solvent casting method. The formulation was evaluated for folding endurance, moisture uptake, pH, drug content and in vitro permeation. Various permeation enhancers were incorporated at 5% w/w concentration into the patch formulationto study their impact on the drug permeation. The TDDS made with Transcutol® as an enhancer was subjected to accelerated stability studies and in vivo skin irritation studies.Results: The developed TDDS showed folding endurance of 170, moisture uptakeof 15.7%, pH of 6.3, and drug content of 99±1.1% and 66% in vitro permeation of doxa over 24h. The effect of various enhancers expressed in terms of average flux can be summarized as Transcutol® (10.6±2.1 µg/cm2h)>dimethyl sulfoxide(10.17±1.2 µg/cm2h)>benzyl alcohol (9.55±1.3 µg/cm2h)>no enhancer (8.86±1.1 µg/cm2h)>dimethyl isosorbide (8.21±1.5 µg/cm2h)>Isostearic acid (7.82±1.4 µg/cm2h)>propylene carbonate (7.67±1.4 µg/cm2h)>oleic acid (7.12 µg±0.8/cm2h). The formulation was found to be stable during the accelerated stability studies. In vivo studies indicated absence of skin irritation effect the TDDS containing Transcutol®.Conclusion: TDDS of doxa comprising HPMC K100LV and PVPK30 in the ratio of 3:1 and 5% Transcutol® could serve as a potential TDDS in the treatment of benign prostatic hyperplasia (BPH) and hypertension.
Summary Report on Workshop on In Vitro Release Test (IVRT) and In Vitro Permeation Test (IVPT) Methods
