Indian Journal of Natural Sciences www.tnsroindia.org.in ©IJONS Vol.10 / Issue 61 / August / 2020 International Bimonthly ISSN: 0976 – 0997 REVIEW ARTICLE A Review on Transdermal Drug Delivery System P.Palanisamy*, B.Jaykar, B.S.Venkateswarlu, R.Margret Chandira, and Suriyan. D Department of Pharmaceutics, Vinayaka Mission’s College of Pharmacy, Vinayaka Mission’s Research Foundation (Deemed to be University), Salem (D.T), Tamil Nadu (State), India. Received: 20 Apr 2020 Revised: 22 May 2020 Accepted: 24 Jun 2020 *Address for Correspondence P.Palanisamy Department of Pharmaceutics, Vinayaka Mission’s College of Pharmacy, Vinayaka Mission’s Research Foundation (Deemed to be University), Salem (D.T), Tamil Nadu (State), India. Email: [email protected] This is an Open Access Journal / article distributed under the terms of the Creative Commons Attribution License (CC BY-NC-ND 3.0) which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. All rights reserved. ABSTRACT Transdermal drug delivery systems (TDDS), additionally called “Transdermal patches,” square measure dose forms designed to deliver a therapeutically effective quantity of drug across a patient’s skin. so as to deliver therapeutic agents through the human skin for general effects, the great morphological, biophysical and chemistry properties of the skin square measure to be thought-about. transcutaneous delivery provides a number one edge over injectables and oral routes by increasing patient compliance and avoiding initial pass metabolism severally. transcutaneous delivery not solely provides controlled, constant administration of the drug, however additionally permits continuous input of medicine with short biological half-lives and eliminates periodical entry into circulation, which frequently causes undesirable side effects. The TDDS review articles offer valuable info relating to the transcutaneous drug delivery systems, styles of Trandermal patches, factors affecting and its analysis method details as a prepared reference for the analysis human United Nations agency is concerned in TDDS. With the advancement in technology company industries have trendified all its resources. Earlier we have a tendency to use convectional dose type however currently we have a tendency to use novel drug delivery system. one in all greatest innovation of novel drug delivery is pad. The advantage of transdermal drug delivery system is that it's painless technique of administration of medicine. Keywords: Transdermal drug delivery system, skin anatomy, polymers used in TDDS types, evaluation parameters. 27035 Indian Journal of Natural Sciences www.tnsroindia.org.in ©IJONS Vol.10 / Issue 61 / August / 2020 International Bimonthly ISSN: 0976 – 0997 P.Palanisamy et al. INTRODUCTION Novel drug delivery system (NDDS) is capable of controlling the speed of drug delivery, sustained the duration of action and targeting the diseased tissue, thereby resulting in better therapeutic effects with minimum side effects (1). Two aspects most important to drug delivery:- Spatial Drug Delivery In this, Drug is targeted to particular organ or tissue. Temporal Drug Delivery The rate of the drug delivery to the target is cotrolled. The main area for the research and development for NDDS are as follors: • Liposomes • Niosomes • Nanoparticles • Transdermal drug delivery • Implants • Oral system • Micro encapsulation / Microcapsules • Polymer in drug delivery Novel drug delivery system can be divided into two main classes. 1. Sustained release drug delivery system. 2. Controlled release drug delivery system. Sustained release drug delivery system It is a pharmaceutical dosage from formulated to retard the release of a therapeutic effect such that the systemic circulation is delayed and/ or prolonged and the plasma profile is sustained in duration .The onset of its pharmaceutical action is usually slow, and therefore the duration of its therapeutic effect is sustained (2). Increase duration of action of drug Reduced dose frequency Once daily oral preparations. Long lasting depot injections (e.g. contraceptives, hormone replacements, antipsychotic drugs) (3). Controlled release drug delivery system This system has a meaning that goes beyond the scope of sustained drug action. It manifests a predictability and reproducibility within the drug release kinetics. The release of drug substances from a controlled release drug delivery system gains at a rate profile that is not only predictable kinetically but also reproduced from one unit to another (4). They are classified as follows:- I. Site-Targeting drug delivery system II. Activation – Modulated drug delivery system III. Feed – Back Regulated drug delivery system IV. Rate programmed drug delivery system (5) 27036 Indian Journal of Natural Sciences www.tnsroindia.org.in ©IJONS Vol.10 / Issue 61 / August / 2020 International Bimonthly ISSN: 0976 – 0997 P.Palanisamy et al. Merits of drug delivery system 1. Better treatment of many chronic illnesses. eg. Cancer,Asthma, Arthritis. 2. Increased Bio- availability. 3. Reduction within the occurrence and badness of untoward systemic side effects associated with high blood plasma drug concentration. 4. Sustenance of the entire amount of drug administered over the amount dose periods. 5. Reduction in the total amount drug administered over the period of drug treatment which reduce occurance of systemic and local side effects. 6. Prevention from first pass metabolism and gastrointestinal tract degradation (6). Limitations Physiological factors such as gastro intestinal enzyme, activates pH /gastric and intestinal transit rates, food and disease which often influence drug bioavailability from conventional dosage forms may interfere with the accuracy of control release and absorption of drug from the system. The products which remain intact may become accommodates at some sites results slow release of drug from the dosage form may produce a high localized concentration of drug which produces local irritation (7). Drugs with half- life of 1hr or less are difficult to be formulated as sustained release formulation. The high rate of elimination of such drugs from the body requires an highly large maintenance dose which provides 8-12 hrs of continuous release (8). Since these products contain an outsized amount of drug. There is a chance of unsafe over dosage, if the product is improperly made and the total drug contained there is released at one time or over too short time of interval. It's difficult to cease the therapy once after administration could also be for reasons of toxicity or the other It's going to be not suitable to encomposs potent drugs in such system. Transdermal drug delivery system (TDDS) has been an increased interest in the drug administration via the skin for both local therapeutic effects on diseased skin (topical delivery) as well as for systemic delivery of drugs (9). The skin as a site of drug delivery features a number of significant advantages over many other routes of drug administration, including the power to avoid problems of gastric irritation, pH and emptying rate effects,(10) avoid hepatic first-pass metabolism thereby increasing the bioavailability of drug, reduce the chance of systemic side effects by minimizing plasma concentrations compared to oral therapy, provide a sustained release of drug at the location of application; rapid termination of therapy by removal of the device or formulation,(11) the reduction of fluctuations in plasma levels of drugs, and avoid pain associated with injections. The transdermal delivery also can eliminate pulsed entry into the circulation, which could often cause undesirable side effects (12). Transdermal drug delivery systems (TDDSs) are often denied as self-contained discrete dosage forms which, when applied to the intact skin, deliver the drug(s) through the skin portal at a predetermined and reproducible rate into the systemic circulation over a prolonged period. The goal of dosage design for transdermal products is to maximise the ux through the skin into the circulation and simultaneously minimize the retention and metabolism of the drug in the skin. Transdermal delivery provides a number one edge over injectable and oral routes by increasing patient compliance and avoiding first-pass metabolism, respectively. The transdermal route is so desirable, however there's one little obstacle: whereas the perform of the GI tract is to render ingested material appropriate for absorption, the skin’s function is to keep things out of the body. The major barrier within the skin is that the stratum corneum, the highest layer of the epidermis. The corneum consists of keratinized, flattened remnants of once actively dividing epidermal cells. Hygroscopic, but impermeable to water, it behaves as a troublesome, flexible membrane. The intercellular space is rich in lipids. The stratum corneum is regarding 10 microns thick, but on the palms and soles it ranges up to 600 microns in thickness .Although the stratum corneum is an efficient barrier, some chemical substances are ready to penetrate it and to achieve the underlying tissues and blood vessels. These “successful” substances are characterised by low molecular weight (≤500 Da), lipophilicity, and effectiveness at low dosage. The largest daily dose of drug in patch kind is that of nicotine: twenty-one milligrams transdermic absorption happens 27037 Indian Journal of Natural Sciences www.tnsroindia.org.in ©IJONS Vol.10 / Issue 61 / August / 2020