Transdermal patches

Transdermal patches have a high systemic impact and may increase absorption by bypassing hepatic first-pass metabolism. A transdermal therapeutic system allows drugs to be continuously administered into the systemic bloodstream at a predetermined rate through unbroken skin over an extended period of time. When piroxicam (PXM) is taken orally, it can cause headaches, exhaustion, dry mouth, nose, and throat, nausea, vomiting, and sleepiness. It is also insoluble in water, so its allure is tainted by its decomposition. These issues are avoided by using a solvent-casting technique on a mercury surface in PXM matrix-type transdermal patches. In HPMC E50LV and Eudragit RS 100 transdermal patches, glycerine (plasticizer) is produced through solvent evaporation and a film-forming polymer. The FTIR method will be used aesthetics, breadth, weight difference, folding durability, moisture content, tensile strength, and percentage of PXM content were all deemed satisfactory on a physical level. According to the study, PXM release from transdermal patches can be improved by combining HPMC E50LV (400 mg) and Eudragit RS 100 (300 mg) with glycerine as a plasticize

  The conventional oral dosage forms has significant drawbacks of low bioavailability due to hepatic first pass metabolism and tendency to produce rapid blood level spikes (Both high and low), leading to a need for frequent dosing, which can be both cost ineffective and inconvenient. To improve such characters transdermal drug delivery system (TDDS) was emerged which will improve the therapeutic efficacy and safety of drugs by more precise (i.e. site specific) placement within the body thereby reducing both the size and number of doses. The TDDS has numerous advantages over the more traditional drug delivery system. These include high bioavailability, absence of first pass hepatic metabolism, maintenance of steady plasma level of the drug, increase therapeutic efficiency. This review article provides an overview of TDDS, its advantages over conventional dosage forms, Limitations, various components of Transdermal patches, types of Transdermal patches, methods of preparation and Ideal requirements for TDDS, regulatory issues over transdermal drug delivery and its physicochemical methods of evaluation. Key words: Transdermal drug delivery systems, Transdermal patches, skin penetration, Topical drug delivery

Timolol maleate, an antihypertensive drug has a half-life of 2-3 hours and a bioavailability of about 60%. It undergoes extensive first pass metabolism. The present study aims to formulate and evaluate Transdermal drug delivery for sustained release of Timolol maleate. The partition coefficient in octanol /water system indicates that the drug is suitable for Transdermal drug delivery. The Physicochemical compatibility of the drug and polymers was studied by IR spectroscopy and the results suggested no physicochemical incompatibility between drugs and the polymers. Total 20 formulations were prepared. The transdermal patches were prepared using different polymers like Hydroxy Propyl Methyl Cellulose, Polyvinyl alcohol and Poly vinyl pyrrolidine in varied ratios, plasticizers like propylene glycol and various permeation enhancers. The patches were evaluated for various parameters like Thickness, weight variation, Water-Vapor Permeability, Tensile Strength, Percent Moisture Uptake, Drug Content, Diffusion and Dissolution studies. The interaction among various components of the matrices was studied by performing Differential Scanning Calorimetry. The Optimized formulation containing PVA: PVP (F 19) in the ratio of 3:2 and containing 30 % propylene glycol as a plasticizer and 2 % Hyaluronidase as a permeation enhancer gave a maximum release 51.68 % (4.75 mg) over a period of 8 hours. Stability studies were carried out as per ICH guidelines and formulations were found to be Stable. Key words: Transdermal patches; Timolol maleate; Differential Scanning Calorimetry (DSC); Infrared spectroscopy (IR); Partition co-efficient.