Transdermal drug delivery systems (TDDS), also known as "patches," are dosage forms designed to deliver a therapeutically effective amount of drug across a patient's skin. The adhesive of the transdermal drug delivery system is critical to the safety, efficacy and quality of the product. In the Drug Quality Reporting System (DQRS), the United States Food and Drug Administration (FDA) has received numerous reports of "adhesion lacking" for transdermal drug delivery systems. This article provides an overview of types of transdermals, their anatomy, the role of adhesion, the possible adhesion failure modes and how adhesion can be measured. Excerpts from FDA reports on the lack of adhesion of transdermal system products are presented. Pros and cons of in vitro techniques, such as peel adhesion, tack and shear strength, in vivo techniques used to evaluate adhesive properties are discussed. To see a decrease in "adhesion lacking" reports, adhesion needs to become an important design parameter and suitable methods need to be available to assess quality and in vivo performance. This article provides a framework for further discussion and scientific work to improve transdermal adhesive performance.

1. THE TOOL FOR NOVEL DRUG DELIVERY- TRANSDERMAL DRUG
DELIVERY SYSTEM
*Rahul Pal, Prachi Pandey, Arsh Chanana, Himmat Singh Chawra, Ravinder Pal Singh
Department of Pharmaceutics, NIMS Institute of Pharmacy NIMS University , Jaipur, Rajasthan
Email. palsrahul330@gmail.com
ABSTRACT FORMULATION OF TRANSDERMAL DRUG
DELIVERY SYSTEM
INTRODUCTION
REFERENCES
COMPOSITION OF TRANSDERMAL PATCHES
The absorption of drug through the skin is very challenging, because there is the first barrier that has to be
passed, the SC. Structurally, the SC is composed of dead keratinocytes which, together the ceramide lipid
component, form a dense structure which is known as a ‘brick-and-mortar’ arrangement.
Generally, drug absorption from the skin via the SC can be distinguished into two pathways,
transepidermal and transappendageal.
• The first pathway and the main absorption route is known as transepidermal.
• The second pathway of drug absorption from the skin is transappendageal which is defined as drug
delivery via hair follicles or sweat glands in the skin.
1. Polymer Matrix or Drug Reservoir
2. Membrane
3. Drug
4. Permeation Enhancers
5. Pressure Sensitive Adhesive (PSA)
6. Backing Laminates
7. Release Linear
8. Other excipients
CONCLUSION/FUTURE PRESPECTIVES
The Transdermal drug delivery system has gained importance in recent years. In recent years, the scale of
TDDS in the domestic and overseas drug delivery system market has increased, as confirmed through
increasing research studies, patents, and commercially available products from many companies and
research institutes.
TDDS has potential advantages of avoiding hepatic first pass metabolism, maintaining constant blood
level for longer period of time resulting in a reduction of dosing frequency, improved BA, decreased GIT
irritation that occur due to local contact with gastric mucosa and improved patient compliance.
The development of TDDS technology is widely recognized as the development of a mass delivery
methodology, which makes it the preferred drug injection modality for transdermal delivery across skin
types.
▪ The development of novel delivery system for existing drug molecules not only improves the drug’s
performance as efficacy and safety but also improves patient compliance and overall therapeutic benefit
to a significant extent.
▪ Transdermal drug delivery systems, topically administered dosage form in the form of patches that
deliver drugs for systemic effects at a predetermined and controlled rate .
▪ The main objective of transdermal drug delivery system is to deliver drugs into systemic circulation
through skin at predetermined rate with minimal inter and intra patient variation.
▪ Currently transdermal delivery is one of the most promising methods for drug applications. In
Transdermal drug delivery system in which the drug Preparation or medicament is applied on the
external surface of skin and Mucus membrane.
▪ It can include in Transdermal Medicament such as Ointment, creams, gels, Micro emulsions,
Transdermal patches is important to prevent the infection of skin and maintain the appropriate health of
skin.
A transdermal patch is a medicated adhesive patch that is placed on the skin to deliver a specific dose of
medication through the skin and into the bloodstream. 76% of drugs can be administered in the oral route of
administration. It cannot give desired therapeutic activity, in the case of a drug under the Transdermal drug
delivery system it can give systemic activity for a prolonged period of time and maintain its Therapeutic
activity. Chewing gum is an obvious drug delivery system for local treatment of diseases in the oral cavity
and in the throat, as sustaining the release of active substances may deliberately prolong exposure. TDDS
are self-contained. Discrete dosage form called “Patches”, when it applies to intact skin, delivers drugs
through skin at controlled rate to systemic circulation. It works very simply in which a drug is applied
inside the patch and it is worn on skin for a long period of time.
Transdermal drug delivery is a recent technology which promises a great future it has a potential to limit
the use of needles for administering different kinds of drugs but cost factor is an important thing to consider
since developing nations like INDIA have second highest population, but due to higher cost TDDS are the
hidden part of therapy used in general population.
There are mainly of four Major Transdermal patches as following-
▪ Polymer Membrane Partition-Controlled System.
▪ Polymer Matrix Diffusion-Controlled System.
▪ Adhesive Dispersion Type System.
▪ Micro Reservoir or Micro Sealed Dissolution Controlled System.
❑ . Polymer Membrane Partition Controlled System.
Example: All are FDA Approval patches example- Transderm-Nitro: For Angina Pectoris Transderm-Scop:
For Motion Sickness, Catapresand Estaderm- For Hypertension.
❑ . Polymer Matrix Diffusion Controlled System.
Example: Nitro-Door: delivery nitroglycerine for treat of angina pectoris, Nitro- Dur, NTS system: Minitran
system and Niro-Dur-II.
❑ . Adhesive Dispersion Type System.
❑ . Micro Reservoir Type OR Microsealed Dissolution.
❑ Example: Technology utilizes in preparation of Nitrodisc – Nitroglycerine, releasing transdermal therapy
system.
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iv. Banker G.S., Chalmers R.K., “Pharmaceutics and Pharmacy Practice”, Ist edition, Lippincott Company, 28-294, 1982.
Presented at the “International Conference on Fostering High Quality Clinical Research for A Healthier World” held at NIMS University, Jaipur
on 26th November 2022.
RECENT TECHNOLOGY/ APPROACH
A recent approach to drug delivery is to deliver the drug into systemic circulation at predetermined rate using
skin as a site of application. Transdermal drug delivery is one of the most promising methods for drug
application. Increasing numbers of drugs are being added to the list of therapeutic agents that can be delivered
to the systemic circulation via skin.
Recent Technology Used in Transdermal Drug Delivery System:
▪ Iontophoresis.
▪ Microneedle-based Device.
▪ Sonophoresis.
▪ Velocity Based Device.
▪ Thermal Ablation.
https://www.mdpi.com/1420-3049/26/19/5905/html
Drug Absorption via the Skin
https://link.springer.com/article/10.1007/s13346-021-00909-6
https://www.frontiersin.org/articles/10.3389/fbioe.2018.00015/full