The document discusses transdermal drug delivery systems (TDDS). It defines TDDS and provides their advantages over other drug delivery methods. It describes the skin structure, especially the stratum corneum layer, and how drugs penetrate the skin through various routes. Factors that affect transdermal drug permeability are outlined. Ideal drug candidates and components of TDDS like polymers and permeation enhancers are also discussed.
Transdermal Drug Delivery System (TDDS) is the one of the novel technology to deliver the molecules through the skin for long period of time.
Transdermal Drug Delivery System (TDDS) are defined as self contained, discrete dosage forms which are also known as “patches” 2, 3 when patches are applied to the intact skin, deliver the drug through the skin at a controlled rate to the systemic circulation
Transdermal Drug Delivery System (TDDS) is the one of the novel technology to deliver the molecules through the skin for long period of time.
Transdermal Drug Delivery System (TDDS) are defined as self contained, discrete dosage forms which are also known as “patches” 2, 3 when patches are applied to the intact skin, deliver the drug through the skin at a controlled rate to the systemic circulation
Controlled Release Oral Drug Delivery System
Controlled drug delivery is one which delivers the drug at a predetermined rate, for locally or systemically, for a specified period of time.
Gastro retentive drug delivery system (GRDDS)Shweta Nehate
Oral route is the most acceptable route for drug administration. Apart from conventional dosage forms several other forms were developed in order to enhance the drug delivery for prolonged time period and for delivering drug to a particular target site. Gastro-retentive drug delivery system (GRDDS) has gainned immense popularity in the field of oral drug delivery recently. it is a widely employed approach to retain the dosage form in the stomach for an extended period of time and release the drug slowly that can address many challenges associated with conventional oral delivery, including poor bioavailability. different innovative approaches are being applied to fabricate GRDDS. Gastroretentive drug delivery is an approach to prolong gastric residence time, there by targeting site-specific drugs release in the upper gastrointestinal tract (GIT) for local or systemic effects. It is obtained by retaining dosage form into stomach and by releasing the in controlled manner.
Easy & to the point Topics are clearly given in this presentation..
Thanks & Best Regard
(Anurag Pandey) B.Pharm
Contact :- anurag.dmk05@gmail.com (Facebook & Gmail both)
Controlled Release Oral Drug Delivery System
Controlled drug delivery is one which delivers the drug at a predetermined rate, for locally or systemically, for a specified period of time.
Gastro retentive drug delivery system (GRDDS)Shweta Nehate
Oral route is the most acceptable route for drug administration. Apart from conventional dosage forms several other forms were developed in order to enhance the drug delivery for prolonged time period and for delivering drug to a particular target site. Gastro-retentive drug delivery system (GRDDS) has gainned immense popularity in the field of oral drug delivery recently. it is a widely employed approach to retain the dosage form in the stomach for an extended period of time and release the drug slowly that can address many challenges associated with conventional oral delivery, including poor bioavailability. different innovative approaches are being applied to fabricate GRDDS. Gastroretentive drug delivery is an approach to prolong gastric residence time, there by targeting site-specific drugs release in the upper gastrointestinal tract (GIT) for local or systemic effects. It is obtained by retaining dosage form into stomach and by releasing the in controlled manner.
Easy & to the point Topics are clearly given in this presentation..
Thanks & Best Regard
(Anurag Pandey) B.Pharm
Contact :- anurag.dmk05@gmail.com (Facebook & Gmail both)
The local drug delivery system is used in dentistry in case of mild to moderate pockets. Many agents and techniques are used for this. For example, tetracycline fibre, chlorhexidine chips, metronidazole, etc.
the all the content in this profile is completed by the teachers, students as well as other health care peoples.
thank you, all the respected peoples, for giving the information to complete this presentation.
this information is free to use by anyone.
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
Overview of Transdermal Drug Delivery Systemijtsrd
Transdermal drug delivery systems are topically administered medicaments. Transdermal drug transport structures TDDS are the dosage shape of adhesive patch this is positioned on the skin to deliver specific dose of medication through the skin and in to the blood stream. The main objective of transdermal drug delivery system is to deliver drug into systemic circulation through skin at predetermined rate with minimal inter and intrapatients variation. This article gives a brief overview over principles behind transdermal drug delivery, as well as the advantages and disadvantages of transdermal therapeutic system and the recent innovations in the field of transdermal drug delivery and also describe the methods of preparation of different types of transdermal patches, evaluation parameters and some available marketed products. Sayali Dhepe | Manisha Sukre | Vikram Veer "Overview of Transdermal Drug Delivery System" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-6 | Issue-4 , June 2022, URL: https://www.ijtsrd.com/papers/ijtsrd50107.pdf Paper URL: https://www.ijtsrd.com/pharmacy/pharmaceutics/50107/overview-of-transdermal-drug-delivery-system/sayali-dhepe
A transdermal patch or skin 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. It enables a steady blood level profile, resulting in reduced systemic side effects and, sometimes, improved efficacy over other dosage forms. The administration of drugs by transdermal route offers the advantage of being relatively painless. The appeal of using the skin as a portal of drug entry lies in case of access, its huge surface area, and systemic access through underlying circulatory and lymphatic networks and the noninvasive nature of drug delivery. The main objective of transdermal patches system is to deliver drugs into systemic circulation through skin at predetermined rate with minimal inter and intrapatient variation.
The first adhesive transdermal delivery system (TDDS) patch was approved by the Food and Drug Administration in 1979 (scopolamine patch for motion sickness). Nitroglycerine patches were approved in 1981. This method of delivery became widely recognized when nicotine patches for smoking cessation were introduced in 1991.
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.
HERBAL TRANSDERMAL PATCHES By SAILI. P. RAJPUT SailiRajput
Wound is the term which means the damage or tearing of cells and its anatomy and cell function. Wound are classified as surgical, traumatic, diabetic, venous, arterial wound and etc. The wound healing is a process which involves coagulation, Ephilization, granulation, and remodelling of tissue.
The proposed study was done and performed to evaluate the wound healing capacity of the herbs like ocimum sanctum (tulsi) and aloe vera when formulated in form of transdermal patches.
In this study Natural wound healing was enhanced by the various phytochemicals present in tulsi and aloe vera. The present study includes the drug delivery through transdermal patches for treating, curing, preventing various skin allergy, infection or wound healing.
The main aim of this study was to formulate the herbal transdermal patches in which tulsi plant extract is loaded in aloe vera patches which help to treat the skin infection like rashes, redness, and in wound healing.
Herbal formulation is still the mainstay about 75-80 % of world’s population in various country for health care because it has fewer side effects. And they also have better compatibility as compare to synthetic drugs.
Herbal formulation consists of the extract of herbs, plants and its part like root system and shoot system which are rich in various phytochemicals which helps to treat various injuries, disease or infection. In various study it has been seen and observed that the plants like tulsi and aloe have the wound healing activities.
Various Research Study and Surveys States that there are Topical and Transdermal Medicated Formulation for Dealing with Treatment of Skin Infections but this Study States the Transdermal Drug Delivery System has wide range of Advantages over Topical Formulation.
In Present Study the Advantage of Transdermal Formulation over Topical Formulation is briefly Discussed. And from various aspects its observed that the transdermal formulation has wide range of advantages over topical formulation. This TDDS has wide scope in future so it involves various New Approaches like Iontophoresis, Photomechanical waves etc.
The Transdermal Drug Delivery System Aims in Drug Targeting and Controlled Release of Drug.
Transdermal Drug Delivery system of Novel Drug Delivery System which also involves various drug delivery systems like Sustain Release system , Delayed release System, Targeted release system, Modified release system, Extended release system and many more.
The Transdermal drug delivery system is used to produce clinical effects like local anesthesia and anti-inflammatory activities.
TDDS has a very wide scope now-a-days because it has many advantages over old and traditional drug delivery systems.
There are wide scope for new innovations in TDDS as is its developing in medical field
TDDS tends to enhance the Bioavailability of and drug and also Bypass the First Pass Metabolism.
TDDS helps to maintain the drug concentration in given therapeutic
Report Back from SGO 2024: What’s the Latest in Cervical Cancer?bkling
Are you curious about what’s new in cervical cancer research or unsure what the findings mean? Join Dr. Emily Ko, a gynecologic oncologist at Penn Medicine, to learn about the latest updates from the Society of Gynecologic Oncology (SGO) 2024 Annual Meeting on Women’s Cancer. Dr. Ko will discuss what the research presented at the conference means for you and answer your questions about the new developments.
Couples presenting to the infertility clinic- Do they really have infertility...Sujoy Dasgupta
Dr Sujoy Dasgupta presented the study on "Couples presenting to the infertility clinic- Do they really have infertility? – The unexplored stories of non-consummation" in the 13th Congress of the Asia Pacific Initiative on Reproduction (ASPIRE 2024) at Manila on 24 May, 2024.
Anti ulcer drugs and their Advance pharmacology ||
Anti-ulcer drugs are medications used to prevent and treat ulcers in the stomach and upper part of the small intestine (duodenal ulcers). These ulcers are often caused by an imbalance between stomach acid and the mucosal lining, which protects the stomach lining.
||Scope: Overview of various classes of anti-ulcer drugs, their mechanisms of action, indications, side effects, and clinical considerations.
MANAGEMENT OF ATRIOVENTRICULAR CONDUCTION BLOCK.pdfJim Jacob Roy
Cardiac conduction defects can occur due to various causes.
Atrioventricular conduction blocks ( AV blocks ) are classified into 3 types.
This document describes the acute management of AV block.
Flu Vaccine Alert in Bangalore Karnatakaaddon Scans
As flu season approaches, health officials in Bangalore, Karnataka, are urging residents to get their flu vaccinations. The seasonal flu, while common, can lead to severe health complications, particularly for vulnerable populations such as young children, the elderly, and those with underlying health conditions.
Dr. Vidisha Kumari, a leading epidemiologist in Bangalore, emphasizes the importance of getting vaccinated. "The flu vaccine is our best defense against the influenza virus. It not only protects individuals but also helps prevent the spread of the virus in our communities," he says.
This year, the flu season is expected to coincide with a potential increase in other respiratory illnesses. The Karnataka Health Department has launched an awareness campaign highlighting the significance of flu vaccinations. They have set up multiple vaccination centers across Bangalore, making it convenient for residents to receive their shots.
To encourage widespread vaccination, the government is also collaborating with local schools, workplaces, and community centers to facilitate vaccination drives. Special attention is being given to ensuring that the vaccine is accessible to all, including marginalized communities who may have limited access to healthcare.
Residents are reminded that the flu vaccine is safe and effective. Common side effects are mild and may include soreness at the injection site, mild fever, or muscle aches. These side effects are generally short-lived and far less severe than the flu itself.
Healthcare providers are also stressing the importance of continuing COVID-19 precautions. Wearing masks, practicing good hand hygiene, and maintaining social distancing are still crucial, especially in crowded places.
Protect yourself and your loved ones by getting vaccinated. Together, we can help keep Bangalore healthy and safe this flu season. For more information on vaccination centers and schedules, residents can visit the Karnataka Health Department’s official website or follow their social media pages.
Stay informed, stay safe, and get your flu shot today!
Ozempic: Preoperative Management of Patients on GLP-1 Receptor Agonists Saeid Safari
Preoperative Management of Patients on GLP-1 Receptor Agonists like Ozempic and Semiglutide
ASA GUIDELINE
NYSORA Guideline
2 Case Reports of Gastric Ultrasound
New Directions in Targeted Therapeutic Approaches for Older Adults With Mantl...i3 Health
i3 Health is pleased to make the speaker slides from this activity available for use as a non-accredited self-study or teaching resource.
This slide deck presented by Dr. Kami Maddocks, Professor-Clinical in the Division of Hematology and
Associate Division Director for Ambulatory Operations
The Ohio State University Comprehensive Cancer Center, will provide insight into new directions in targeted therapeutic approaches for older adults with mantle cell lymphoma.
STATEMENT OF NEED
Mantle cell lymphoma (MCL) is a rare, aggressive B-cell non-Hodgkin lymphoma (NHL) accounting for 5% to 7% of all lymphomas. Its prognosis ranges from indolent disease that does not require treatment for years to very aggressive disease, which is associated with poor survival (Silkenstedt et al, 2021). Typically, MCL is diagnosed at advanced stage and in older patients who cannot tolerate intensive therapy (NCCN, 2022). Although recent advances have slightly increased remission rates, recurrence and relapse remain very common, leading to a median overall survival between 3 and 6 years (LLS, 2021). Though there are several effective options, progress is still needed towards establishing an accepted frontline approach for MCL (Castellino et al, 2022). Treatment selection and management of MCL are complicated by the heterogeneity of prognosis, advanced age and comorbidities of patients, and lack of an established standard approach for treatment, making it vital that clinicians be familiar with the latest research and advances in this area. In this activity chaired by Michael Wang, MD, Professor in the Department of Lymphoma & Myeloma at MD Anderson Cancer Center, expert faculty will discuss prognostic factors informing treatment, the promising results of recent trials in new therapeutic approaches, and the implications of treatment resistance in therapeutic selection for MCL.
Target Audience
Hematology/oncology fellows, attending faculty, and other health care professionals involved in the treatment of patients with mantle cell lymphoma (MCL).
Learning Objectives
1.) Identify clinical and biological prognostic factors that can guide treatment decision making for older adults with MCL
2.) Evaluate emerging data on targeted therapeutic approaches for treatment-naive and relapsed/refractory MCL and their applicability to older adults
3.) Assess mechanisms of resistance to targeted therapies for MCL and their implications for treatment selection
Explore natural remedies for syphilis treatment in Singapore. Discover alternative therapies, herbal remedies, and lifestyle changes that may complement conventional treatments. Learn about holistic approaches to managing syphilis symptoms and supporting overall health.
These lecture slides, by Dr Sidra Arshad, offer a quick overview of physiological basis of a normal electrocardiogram.
Learning objectives:
1. Define an electrocardiogram (ECG) and electrocardiography
2. Describe how dipoles generated by the heart produce the waveforms of the ECG
3. Describe the components of a normal electrocardiogram of a typical bipolar leads (limb II)
4. Differentiate between intervals and segments
5. Enlist some common indications for obtaining an ECG
Study Resources:
1. Chapter 11, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 9, Human Physiology - From Cells to Systems, Lauralee Sherwood, 9th edition
3. Chapter 29, Ganong’s Review of Medical Physiology, 26th edition
4. Electrocardiogram, StatPearls - https://www.ncbi.nlm.nih.gov/books/NBK549803/
5. ECG in Medical Practice by ABM Abdullah, 4th edition
6. ECG Basics, http://www.nataliescasebook.com/tag/e-c-g-basics
Title: Sense of Taste
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the structure and function of taste buds.
Describe the relationship between the taste threshold and taste index of common substances.
Explain the chemical basis and signal transduction of taste perception for each type of primary taste sensation.
Recognize different abnormalities of taste perception and their causes.
Key Topics:
Significance of Taste Sensation:
Differentiation between pleasant and harmful food
Influence on behavior
Selection of food based on metabolic needs
Receptors of Taste:
Taste buds on the tongue
Influence of sense of smell, texture of food, and pain stimulation (e.g., by pepper)
Primary and Secondary Taste Sensations:
Primary taste sensations: Sweet, Sour, Salty, Bitter, Umami
Chemical basis and signal transduction mechanisms for each taste
Taste Threshold and Index:
Taste threshold values for Sweet (sucrose), Salty (NaCl), Sour (HCl), and Bitter (Quinine)
Taste index relationship: Inversely proportional to taste threshold
Taste Blindness:
Inability to taste certain substances, particularly thiourea compounds
Example: Phenylthiocarbamide
Structure and Function of Taste Buds:
Composition: Epithelial cells, Sustentacular/Supporting cells, Taste cells, Basal cells
Features: Taste pores, Taste hairs/microvilli, and Taste nerve fibers
Location of Taste Buds:
Found in papillae of the tongue (Fungiform, Circumvallate, Foliate)
Also present on the palate, tonsillar pillars, epiglottis, and proximal esophagus
Mechanism of Taste Stimulation:
Interaction of taste substances with receptors on microvilli
Signal transduction pathways for Umami, Sweet, Bitter, Sour, and Salty tastes
Taste Sensitivity and Adaptation:
Decrease in sensitivity with age
Rapid adaptation of taste sensation
Role of Saliva in Taste:
Dissolution of tastants to reach receptors
Washing away the stimulus
Taste Preferences and Aversions:
Mechanisms behind taste preference and aversion
Influence of receptors and neural pathways
Impact of Sensory Nerve Damage:
Degeneration of taste buds if the sensory nerve fiber is cut
Abnormalities of Taste Detection:
Conditions: Ageusia, Hypogeusia, Dysgeusia (parageusia)
Causes: Nerve damage, neurological disorders, infections, poor oral hygiene, adverse drug effects, deficiencies, aging, tobacco use, altered neurotransmitter levels
Neurotransmitters and Taste Threshold:
Effects of serotonin (5-HT) and norepinephrine (NE) on taste sensitivity
Supertasters:
25% of the population with heightened sensitivity to taste, especially bitterness
Increased number of fungiform papillae
ARTIFICIAL INTELLIGENCE IN HEALTHCARE.pdfAnujkumaranit
Artificial intelligence (AI) refers to the simulation of human intelligence processes by machines, especially computer systems. It encompasses tasks such as learning, reasoning, problem-solving, perception, and language understanding. AI technologies are revolutionizing various fields, from healthcare to finance, by enabling machines to perform tasks that typically require human intelligence.
Title: Sense of Smell
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the primary categories of smells and the concept of odor blindness.
Explain the structure and location of the olfactory membrane and mucosa, including the types and roles of cells involved in olfaction.
Describe the pathway and mechanisms of olfactory signal transmission from the olfactory receptors to the brain.
Illustrate the biochemical cascade triggered by odorant binding to olfactory receptors, including the role of G-proteins and second messengers in generating an action potential.
Identify different types of olfactory disorders such as anosmia, hyposmia, hyperosmia, and dysosmia, including their potential causes.
Key Topics:
Olfactory Genes:
3% of the human genome accounts for olfactory genes.
400 genes for odorant receptors.
Olfactory Membrane:
Located in the superior part of the nasal cavity.
Medially: Folds downward along the superior septum.
Laterally: Folds over the superior turbinate and upper surface of the middle turbinate.
Total surface area: 5-10 square centimeters.
Olfactory Mucosa:
Olfactory Cells: Bipolar nerve cells derived from the CNS (100 million), with 4-25 olfactory cilia per cell.
Sustentacular Cells: Produce mucus and maintain ionic and molecular environment.
Basal Cells: Replace worn-out olfactory cells with an average lifespan of 1-2 months.
Bowman’s Gland: Secretes mucus.
Stimulation of Olfactory Cells:
Odorant dissolves in mucus and attaches to receptors on olfactory cilia.
Involves a cascade effect through G-proteins and second messengers, leading to depolarization and action potential generation in the olfactory nerve.
Quality of a Good Odorant:
Small (3-20 Carbon atoms), volatile, water-soluble, and lipid-soluble.
Facilitated by odorant-binding proteins in mucus.
Membrane Potential and Action Potential:
Resting membrane potential: -55mV.
Action potential frequency in the olfactory nerve increases with odorant strength.
Adaptation Towards the Sense of Smell:
Rapid adaptation within the first second, with further slow adaptation.
Psychological adaptation greater than receptor adaptation, involving feedback inhibition from the central nervous system.
Primary Sensations of Smell:
Camphoraceous, Musky, Floral, Pepperminty, Ethereal, Pungent, Putrid.
Odor Detection Threshold:
Examples: Hydrogen sulfide (0.0005 ppm), Methyl-mercaptan (0.002 ppm).
Some toxic substances are odorless at lethal concentrations.
Characteristics of Smell:
Odor blindness for single substances due to lack of appropriate receptor protein.
Behavioral and emotional influences of smell.
Transmission of Olfactory Signals:
From olfactory cells to glomeruli in the olfactory bulb, involving lateral inhibition.
Primitive, less old, and new olfactory systems with different path
The hemodynamic and autonomic determinants of elevated blood pressure in obes...
TRANSDERMAL DRUG DELIVERY SYSTEM
1. TRANSDERMAL DRUG
DELIVERY SYSTEM (TDDS)
Dr. Gajanan S. Sanap M.Pharm.,Ph.D
Department of Pharmaceutics
Ideal College of Pharmacy and Research
Kalyan 421- 306
2. CONTENTS
INTRODUCTION
ADVANTAGES AND LIMITATIONS
SKIN AND EPIDERMIS STRUCTURE
COMPONENTS OF TRANSDERMAL PATCH
TYPES OF TRANSDERMAL PATCH
FACTORS AFFECTING TRANSDERMAL PERMEABILITY
POLYMERS
THERAPIES THAT USE TRANSDERMAL DELIVERY OF
DRUGS
CLASSIFICATION OF TDDS
BASIC COMPONENTS OF TDDS
EVALUATION
REFERENCE
3. When one hears the words transdermal drug delivery, what comes to
mind? More than likely one thinks about a simple patch that one stick
onto skin like an adhesive bandage such as nicotine patch.
The NDDS may involve a new dosage form e.g., from thrice a day
dosage to once a day dosage form or developing a patch form in
place of injections.
Throughout the past 2 decades, the transdermal patch has become a
proven technology that offers a variety of significant clinical
benefits over other dosage forms.
Because transdermal drug delivery offers controlled release of the
drug into the patient, it enables a steady blood-level profile,
resulting in reduced systemic side effects and, sometimes, improved
efficacy over other dosage forms
History of TDDS
4. Transdermal drug delivery system was first introduced more than 20
years ago.
The technology generated tremendous excitement and interest amongst
major pharmaceutical companies in the 1980s and 90s.
First transdermal patch was approved in 1981 to prevent the nausea
and vomiting associated with motion sickness, the FDA has approved,
throughout the past 22 years, more than 35 transdermal patch products,
spanning 13 molecules.
1970-- Alza Research (US) began first development of the modern
transdermal
1980-- Scopolamine first transdermal reached US
2002– Many Rx and non-RX products in US market.
Transdermals deliver drugs from a few hours up to
7 days.
5. Transdermal delivery represents an attractive alternative to oral
delivery of drugs and is poised to provide an alternative to
hypodermic injection too.
For thousands of years, people have placed substances on the skin
for therapeutic effects.
Definition:
Transdermal drug delivery is defined as a self contained discrete
dosage form, which when applied to the intact skin, will deliver the
drug at a controlled rate to the systemic circulation.
Or
Transdermal drug delivery systems (patches) are dosage forms
designed to deliver a therapeutically effective amount of drug across
a patient’s skin also defined as Medicated adhesive patch that is
placed on the skin to deliver a specific dose of Medication through
the skin and into the blood stream.
6. Why transdermal drug delivery?
• Continuous IV administration at a constant rate of
infusion is a superior mode of drug delivery
• IV administration avoids hepatic first-pass metabolism
and maintain constant therapeutic drug levels in the
body
• TDD can closely duplicate continuous IV fusion.
Hence it is helpful in delivering drugs that undergo
significant first pass metabolism and/or have narrow
therapeutic index
7. Principles of diffusion through membranes
Homogenous
membrane
Aqueous
pores
Cellulose
fibres
(1) Diffusion - random molecular motion. Must have concentration gradient.
9. POTENTIAL BENEFITS OF TRANSDERMAL DRUG
DELIVERY (ADVANTAGES)
• Easy to use.
• Avoid GIT absorption problems for drugs.
• Avoids FP hepatic metabolism of drugs.
• More improved and convenient patient compliance.
• Rapid termination in case of toxicity is possible.
• Self medication is possible.
• Reduces frequency of dosing.
• Maintains therapeutic level for 1 to 7 days.
• Controlled delivery resulting in more reliable and predictable
blood levels.
10. DISADVANTAGES
• Daily dose of more than 10mg is not possible.
• Local irritation is a major problem.
• Drug requiring high blood levels are unsuitable.
• Drug with long half life can not be formulated in TDDS.
• Uncomfortable to wear.
• May not be economical.
• Barrier function changes from person to person and within the
same person.
• Heat, cold, sweating (perspiring) and showering prevent the
patch from sticking to the surface of the skin for more than one
day. A new patch has to be applied daily.
11. LIMITATIONS OF TDD
Limited skin permeability
Significant lag time
Cannot be used for large molecule (>500 Dalton)
Restricted to potent drug
Skin irritation and allergic response
Tolerance inducing drugs or those (e.g., hormones) requiring
chronopharmacological management are not suitable candidates.
• Skin structure poses a barrier on the mw of the drug (< 500 Da)
• Usually reserved for drugs which are extremely potent (thus
requiring a dosage of only a few mg).
– The largest daily dose of a drug from a patch is the nicotine
patch, with delivers a daily dose of only 21 mg.
12. Consideration of TDS development
Bioactivity of drug
Skin characteristics
Formulation
Adhesion
System design
Factors influence the permeation of drugs
Skin structure and its properties.
The penetrating molecule and its physical-chemical
relationship to skin and the delivery platform
The platform or delivery system carrying the penetrant
The combination of skin, penetrant and delivery system
14. Epidermis:
The outer layer of skin is made up of Stratified Squamous epithelial
cells.
Epidermis is thickest in palms and soles.
The stratum corneum forms the outer most layer (10-15µm thick ) which
consists of many layers of compacted , flattened, dehydrated keratinized
cells.
Keratin contains cells called as Corneosites.
Stratum corneum layer forms permeability barrier for external
environment.
Water content of stratum corneum is around 20%.
The moisture required for stratum corneum is around 10% (w/w) to
maintain flexibility and softness.
It consists of Cermides and neutral lipids such as Sterols, free fatty acids
and triglycerides.
The stratum corneum is responsible for the barrier function of the skin
and behaves as a primary barrier to the percutaneous absorption.
15. It is made up of three layers in thicker parts stratum granulosum,
stratum lucidum,stratum spinosum.
Removal of these layers results in increased permeability and water
loss.
18. DERMIS:
The dermis is made up of regular network of robust collagen fibers of fairly
uniform thickness with regularly placed cross striations .
This network or the gel structure is responsible for the elastic properties of the
skin.
It is supplied by blood to convey nutrients, remove waste & regulate body
temp.
Drug is well absorbed by this route.
Upper portion of the dermis is formed into ridges containing lymphatics and
nerve endings.
SUBCUTANEOUS TISSUE:
This is a sheet of the fat containing areolar tissue known as the
superficial fascia attaching the dermis to the underlying structures .
SKIN APPENDAGES:
Sweat glands produces sweat of pH 4-6.8 & absorbs drugs, secretes
proteins, lipids and antibodies. Its function is to control heat.
HAIR FOLLICLES
They have sebaceous glands which produces sebum and includes
glycerides, cholesterol and squalene.
19. ROUTES OF DRUG PENETRATION
SWEAT DUCT
ACROSS STRATUM CORNEUM
HAIR FOLLICLES
INTERCELLULAR
TRANSCELLULAR
Macro routes
Micro routes
It involves passive diffusion of substance through skin.
PERCUTANEOUS ABSORPTION
22. Trans follicular route:
Fractional area available through this route is 0.1 %
Human skin contains 40-70 hair follicles, 200 to 250 sweat glands on every sq.cm.
of skin area.
Mainly water soluble substance are diffused faster through appendages than that of
other layers.
Sweat glands and hair follicles act as a shunt i.e. easy pathway for diffusion throug
h rate limiting ST corneum.
Trans Epidermal route
Epidermal barrier function mainly resides in horny layer
The viable layer may metabolize, inactivate or activate a prodrug.
Dermal capillary contains many capillaries so residence time of drug is only one
minute.
Within stratum corneum molecule may penetrate either transcellularly or intercellular.
Intracellular region is filled with lipid rich amorphous material.
23. Routes of drug absorption through skin
Trans follicular route
Trans epidermal route
25. Mechanism of absorption through skin
Mechanism involved is passive diffusion
This can be expressed by FICK’s LAW of DIFFUSION
dq = D K A ( c1 – c2 )
dt h
dq /dt = rate of diffusion
D = diffusion co-efficient
K = partition co- efficient
A = surface area of membrane
H = thickness of membrane
26. FACTORS AFFECTING TRANSDERMA
L PERMEABILITY
Physico chemical properties of parent molecule
Solubility and partition co- efficient
pH condition
Penetrant concentration
Physico chemical properties of drug delivery system
Release characteristic
Composition of drug delivery system
Permeation enhancer used
27. Physiological and pathological condition of skin
Lipid film
Skin hydration
Skin temperature
Effect of vehicle
Pathological injury to skin
Biological factors
Skin age
Thickness of S. Corneum
Skin condition
28. Solubility and partition co- efficient:
Solubility of a drug influences its ability to penetrate the skin.
pKa is index of solubility of drug in vehicle and ST corneum has
influence on transfer of drug from vehicle to skin.
Drug solubility determines concentration presented to absorption
site which will effect rate and extent of absorption.
Skin permeation can be enhanced by increasing lipophilic character
of drug, so that drug penetrates through STC but not through
epidermis due to decreased water solubility.
Drug which is lipid & water soluble is favored.
29. pH & penetration concentration:
Moderate pH is favorable because if solutions with high
or low pH will result in destruction to the skin.
Higher the concentration of the drug in vehicle faster the
absorption.
At higher concentrations than solubility the excess solid
drug will function as a reservoir and helps to maintain a
constant drug constitution for prolonged period of time.
30. Physico-chemical properties of drug delivery system
Release characteristic
Solubility of drug in vehicle determines the release rate.
Composition of drug delivery system
It not only effects the rate of drug release but also the
permeability of STC by means of hydration mixing with skin lipids.
Example methyl salicylate is more lipophilic than its parent acid
(Salicylic acid). When applied to skin from fatty vehicle
methylsalicylate yielded higher absorption.
FACTORS AFFECTING TRANSDERMAL
PERMEABILITY
31. Physiological and pathological condition of skin
Lipid film:
It acts as protective layer to prevent removal of
moisture from skin. Defeating of this film will decrease TD
absorption.
Skin hydration:
It can be achieved by covering skin with plastic
sheeting, which leads to accumulation of sweat, condensed
water vapors, increase hydration and increase porosity.
FACTORS AFFECTING TRANSDERMAL
PERMEABILITY
32. Effect of vehicle:
A vehicle can influence absorption by its effect on
physical state of drug and skin. Example greases, paraffin
bases are more occlusive while water in oil bases are less.
Humectants in bases will dehydrate the skin and decrease
percutaneous absorption.
FACTORS AFFECTING TRANSDERMAL
PERMEABILITY
33. Biological factors:
Skin age:
Skin of foetus, young ones and elders is more
permeable than adult tissue.
Skin metabolism:
Viable epidermis is metabolically active than
dermis. If topically applied drug is subjected to
biotransformation during permeation local and systemic
bioavailability is affected.
FACTORS AFFECTING TRANSDERMAL
PERMEABILITY
34. 1. Must be non-ionic
2. Low molecular weight (less than 500 Daltons)
3. Lipophilicity (Log Ko/w: 1-3)
4. Low melting point (less than 200 degree C)
5. Dose is less than 50 mg per day, and ideally less t
han 10 mg per day.
IDEAL DRUG CANDIDATE FOR TDD
35. BASIC COMPONENTS OF TDDS
Polymer matrix
The drug
Permeation enhancers
Other excipients
1.Polymer matrix
Ideal polymer
MWT, and chemical functionality of the polymer should not affect
the diffusivity of drug and its release
Stable
non reactive
easily manufactured
easily fabricated into desired product
Inexpensive
degaradation product must be non toxic or non antagonistic to the host
Should retain its mechanical properties when the large amount of drug is
loaded in to it.
37. 2. Suitable drug candidate
Physico chemical properties of drug
Should have MW less than 1000 daltons(800-1000)
Should have affinity for both lipophilic and hydrophilic phases
Should have low melting pont
Biological properties of drug
Should be potent(less than 20mg)
Half life should be short
Must not induce a cutaneous irritant or allergic response
Drugs which degrade in the GI tract or inactivated by hepatic first
pass effect are suitable candidate
Tolerance to the drug must not develop
Drugs which has to be administered for a longer period of time can
be formulated
Drugs which cause adverse effects to non target tissues can also be
formulated
38. 3.PERMEATION ENHANCERS
(to enhance stratum corneum permeability)
Solvents
Increases penetration by swelling the polar pathway transport or fluidising lipids
Eg.water,ethanol,methanol,DMS,homologs of methyl sulphoxide,dimethyl acetamide,and
DMF,2-pyrrolidone,N-methyl,2-pyrrolidone,laurocapram,PG,glycerol,silicone fluids,isopr
opyl palmitate.
Surfactants
Enhances the polar pathway transport of hydrophilic drugs
Anionic surfactants
Dioctyl sulpho succinate,SLS,deco decylmethyl sulphoxide etc.
Non ionic surfactants
Pluronic F127,Pluronic F68,etc.
Bile salts
Sodium taurocholate,sodium deoxy cholate,sodium tauroglycocholate.
Binary systems
Propylene glucol-oleic acid and 1,4-butane diol-linoleic acid
Miscellaneous
Urea-hydrating and keratolytic agent,N,N-dimethyl-m-toluamide,calcium thioglycolate,ant
i cholinergic agents
Potential permetion enhancers
Euclyptol,di-o-methyl-ß-cyclodextrin and soyabean casein
39. Permeability Coefficient Is the Critical Predictor
of Transdermal Delivery
Transport = Flux = (mg/cm
2
/sec) = P x A x (Cd – Cr)
Permeability Coefficient = P = D x K (cm/sec)
h
Where A = Surface area of patch
D = Diffusivity of drug in membrane (skin)
K = Partition coefficient (patch/skin)
C = Concentration in donor or receptor
(patch or skin)
h = Thickness of membrane (skin)
40. General terms
Backing - The material, i.e. film, foam, nonwoven, etc.
, used as the outermost layer of the transdermal or
medical system to protect the product during the
wear period.
Membrane - A material placed between the drug
formulation and the final layer of adhesive. The diffusion
properties of the membrane are used to control
availability of the drug and/or excipients to the skin.
41. Liner - The film, removed and discarded prior to p
atch application, that protects the transdermal syst
em by covering the adhesive side.
Laminate - Two or more materials combined in lay
ers to form a single substrate.
Occlusive - Refers to a material’s ability to limit dif
fusion. Generally used in characterization of backin
gs with respect to moisture vapor and oxygen diffu
sion. An occlusive backing would have very low dif
fusion rates.
42. 4.OTHER EXCIPIENTS Adhesives
pressure sensitive polymeric adhesive .
Serves to adhere the components of the patch together along with adhering
the patch to the skin.
Ideal properties
Should not irritate or sensitize the skin or affect normal functions of the skin
Should adhere to the skin aggressively
Should be easily removed
Should not leave an un washable residue on the skin
Should have an intimate contact with the skin
Should be compatible with the drug,excipients and permeation enhancers
Permeation of drug should not be affected
THREE MAJOR FAMILIES OF PSAS:
1. Rubber-based PSAs,
2. Acrylic PSAs in the form of acrylic solutions,
3. Emulsion polymers or hot melts, and silicon PSAs
43. BACKING FILMS /membrane
ROLE OF FILM :
1. To protect the active layer and safeguard the stability of the
system,
2. To affect skin permeation and tolerance, depending on
occlusion or breathability.
3. It must also be flexible, comfortable and must present good
affinity with the adhesive, as well as excellent printability.
Ideal properties
Flexible and provide good bond to the drug reservoir
Prevent drug from leaving the dosage form
Should be impermeable
E.g. metallic plastic laminate, plastic backing with absorbent pad and
occlusive base plate, adhesive foam pad with occlusive base plate.
MOST COMMON MATERIALS USED : polypropylene,
polyethylene (both high and low density), aran, polyesters,
PVC,and nylon.
44. RELEASE LINERS
ROLE OF FILM :
1. To protect the system as long as it is in the package.
2. Play a crucial role in the stability of the product .
3. An incorrect release liner does not permit the easy release of the
patch, and can interfere with the active(s) or other components,
thereby reducing its shelf life.
MOST COMMON FILMS USED :
paper-based,
plastic film-based and
composite films.
TWO MAJOR CLASSES OF ANTI-ADHERENT COATING :
silicones and fluoro-polymers.
45. A release liner is a film covered with an anti-adherent coating.
To protect the system as long as it is in the package, and it is
removed just before the adhesion of the TDDS to the skin.
During storage the patch is covered by a protective liner that is
removed & discharged immediately before the application of the
patch to the skin.
It is there fore regarded as a part of primary packing material rather
than a part of dosage form for delivering the drug.
46. MICROPOROUS OR SEMI-PERMEABLE MEMBRANES or rate
controlling mambrne
The function depends on the design of the specific system, the size
of the active component and the need to have a rate-limiting factor
in order to satisfy the release and absorption characteristics of the
system.
ROLE OF THE MEMBRANES
To limit the flow of the semi-solid content from the liquid reservoir,
and/or to act as a rate-limiting membrane for both liquid reservoir and
matrix systems.
TWO TYPES OF POROUS MEMBRANES
I Ethylene Vinyl Acetate Membranes (EVA)
II Microporous Polyethylene Membranes
47. POUCHING MATERIALS
ROLE :
1. Stability and integrity of the product
THREE MAIN LAYERS IN THE COMPOSITE
MATERIALS USED FOR POUCHES:
1. Internal plastic heat sealable layer,
2. Aluminium foil layer
3. External printable layer.
49. Formulation of TDDS
1.Membrane-moderated or Permeation controlled TDDS (Reservoir
type)
• Drug reservoir (homogenous dispersion of drug with polymeric matrix
or suspension of drug in un leachable viscous liquid medium such as
silicone fluid) is encapsulated within drug impermeable metallic plastic
laminate and a rate controlling polymeric membrane (ethylene vinyl
acetate co polymer)
• The cross sectional view of this system is shown in the following Fig.1
50. RESERVOIR SYSTEM ( MEMBRANE MODERATED TDDS )
TransdermScop® (Scopolamine) for 3 days protection of motion sickness
The drug reservoir is encapsulated in a shallow compartment moulded from a
drug impermeable metallic – plastic lamination whilst the drug delivery side is
covered by controlling polymeric membrane.
51. • A thin layer of silicone or poly acrylate adhesive may be applied to the
external surface of the rate controlling membrane to achieve intimate
contact of the TDDS and the skin surface
• Release rate of this TDDS depends upon the polymer composition,
permeability co efficient and thickness of the rate controlling membrane
and adhesive
• The intrinsic rate of drug release from this TDDS is calculated by the
following formula.1
CR
dQ/dt= --------------------
1/Pm+1/Pa
CR-con.of drug in the reservoir compartment
Pm-permeability co efficient of rate controlling polymeric
membrane
Pa- permeability co efficient of adhesive
52. Drug mixed with polymer
solution
Drug suspended in
polymer solution
Volume controlled
injection pump system
Molding as TDDS using
primary packing material
Packing machinery using
secondary packing material
Transdermal therapeutic
system
53. Example of this system are
1.Nitro glycerin releasing TDDS (Transderm-Nitro/ciba,USA)for once a
day medication in angina pectoris
2.Scopolamine releasing TDDS (Transderm-Scop/ciba,USA)for 72
hrs.prophylaxis of motion sickness
3. Estradiol releasing TDDS (Estraderm/ciba)for treatment of menopausal
syndrome
4. Clonidine releasing TDDS (Catapres/Boehringer Ingelheim)for 7 day
therapy of hyper tension
5. Prostaglandin-derivatives TDDS
54. 2.Adhesive diffusion/dispersion-controlled TDDS
Drug reservoir
– homogenous dispersion of drug with adhesive polymer
(poly(isobutylene) or poly acrylate)
– Then spreading of this medicated adhesive polymer on flat sheet of drug
impermeable metallic plastic backing to form thin drug reservoir layer
– On top of the drug reservoir layer, thin layers of rate controlling
adhesive polymer of specific permeability and constant thickness are
applied to produce an adhesive diffusion/dispersion-controlled TDDS
– The cross sectional view of this system is shown in the following Fig.2
55. • It is the simplified form of membrane moderated drug delivery system
• It is prepared by directly dispensing the drug in an adhesive polymer &
then spreading the medicated adhesive by solvent film casting method
over a flat sheet of drug impermeable metallic or plastic backing
membrane, this forms a thin drug reservoir layer.
Deponit® (Nitroglycerine) for once a day medicatin of angina pectoris.
56. • The rate of drug release in this system is defined by
Ka/r.Da
dQ/dt= -----------------cR
ha
Where
Ka/r-partition co-efficient of drug bw adhesive layer and reservoir layer
Da-diffusion co-efficient of drug in the adhesive layer
ha-thickness of adhesive layer
Examples for this system
1.Iso sorbide dinitrate-releasing TDDS
2.Verapamil releasing TDDS
57. 3.Matrix diffusion-controlled TDDS
Drug reservoir
• homogenous dispersion of drug with hydrophilic or lipophilic polymer
matrix by any one of the following methods
• Homogenous dispersion of finely ground drug particles with liquid polymer
or highly viscous base polymer followed by cross linking of polymer chains
• Homogenous mixing of drug solid with rubbery polymer at an elevated
temperature
• Dissolving the drug and polymer in a common solvent followed by solvent
evaporation in a mould at an elevated temperature or under vacuum.
• Medicated polymer is moulded in to desired surface area and controlled
thickness
• This medicated polymer disc is pasted on to an occlusive base plate with
impermeable plastic backing
• Then the adhesive polymer is spread along the circumference to form a strip
of adhesive rim around the medicated disc
58. Example of this system are
1.Nitro glycerin releasing TDDS (Nitro-Dur and Nitro-Dur II /Key
pharmaceuticals,USA)
2. Estradiol di acetate releasing TDDS
3. Verapamil releasing TDDS
The cross sectional view of this system is shown in the following Fig.3
59. MATRIX SYSTEM --- MATRIX DISPERSION SYSTEM
(MATRIX DIFFUSION CONTROLLED SYSTEM)
MATRIX SYSTEM --- MATRIX DISPERSION SYSTEM
(MATRIX DIFFUSION CONTROLLED SYSTEM)
Nitro Dur® (Nitroglycerine) used for once a day medication of angina
pectoris.
60. • the rate of drug release from this sytem is defined as
where
A initial drug loading dose
Cp and Dp are solubility and diffusivity of drug in poymer matrix
the rate of drug release from this system at steady state is defined as
Q/t1/2= [(2A-Cp) Cp Dp] 1/2
61. 4.Micro reservoir type/micro sealed dissolution- controlled TDDS
Combination of the reservoir and matrix diffusion
Drug reservoir
Suspension of drug with aqueous solution of water soluble liquid polymer
Homogenous dispersion of drug suspension in a lipophilic polymer(silicone
elastomer)
As a result discrete un leachable microscopic spheres of drug reservoir is
formed which is stabilized by cross linking
Medicated polymer is moulded in to desired surface area and controlled
thickness and it is coated with a layer of bio compatible polymer to modify
mechanism and rate of drug release
This medicated polymer disc is pasted on to an occlusive base plate with
impermeable plastic backing
Then the adhesive polymer is spread along the circumference to form a strip
of adhesive rim around the medicated disc
62. Example of this system are
1.Nitro glycerin releasing TDDS (Nitro-Dur and Nitro-Dur II /Key
pharmaceuticals,USA)
2. Estradiol di acetate releasing TDDS
3. Verapamil releasing TDDS
The cross sectional view of this system is shown in the following Fig.4
76. 1. Blending
•The first step in manufacturing a patch is blending, where active
drug compounds are mixed with custom adhesives in large,
specialized kettles.
• After blending is complete, the drug/adhesive mix is pumped to the
next machine for coating.
77. 2. Coating process
In the coating process, a thin, precise drug/adhesive layer
is applied within tolerances of about one-tenth the
thickness of a human hair to long, broad sheets of release
liner material.
78. 3. The blending solvent is
removed in the large arch tunnel
oven
79. 4. Lamination of backing
then the final layer of the three-layer patch – the backing – is
laminated. Although initially applied to the release liner, the
adhesive matrix permanently bonds to the patch backing. The
completed laminate is then rolled for the next production step
80. 5. Rolling of the laminate
The laminate rolls are then sent through punching, pouching and
cartoning machines specially configured for each product.
81. 6. Punching
Dosing is controlled in part by patch size, and patches of
precisely the proper size are punched from the laminate
sheet
83. EVALUATION OF TDDS
TESTS DONE ON FINAL PRODUCT TESTS
CHEMICAL TEST
Content
Content uniformity
Purity
Residual solvent
PHYSICAL TEST
Release testing
USP apparatus 5 (Paddle over disk)
USP apparatus 6 (Cylinder)
USP apparatus 7 (Reciprocating disk)
Franz Diffusion Cell
Test for adhesion
Peel adhesion
Tack property
Thumb tack test
Rolling ball tack test
Quick-stick (peel tack test)
Probe tack test
Shear strength
CUTANEOUS TOXICITY
Contact dermatitis
Growth of microorganisms
Cytotoxicity
Sensitization study
PERCUTANEOUS ABSORPTION MODEL
In vitro testing
In vivo testing
Human IVIVC
84. 1. Thickness of the patch:
The thickness of the drug loaded patch is measured in different points by using a
digital micrometer and determines the average thickness and standard deviation for
the same to ensure the thickness of the prepared patch.
2. Weight uniformity:
The prepared patches are to be dried at 60°c for 4hrs before testing. A specified
area of patch is to be cut in different parts of the patch and weigh in digital balance.
The average weight and standard deviation values are to be calculated from the
individual weights.
3. Folding endurance:
A strip of specific are is to be cut evenly and repeatedly folded at the same place
till it broke. The number of times the film could be folded at the same place
without breaking gave the value of the folding endurance.
4. Percentage Moisture content:
The prepared films are to be weighed individually and to be kept in a desiccator
containing fused calcium chloride at room temperature for 24 hrs. After 24 hrs the
films are to be reweighed and determine the percentage moisture content from the
below mentioned formula.
Percentage moisture content = [Initial weight- Final weight/ Final weight] ×100.
6/ initial weight] ×100.
85. 5. Percentage Moisture uptake:
The weighed films are to be kept in a desiccator at room temperature for 24 hrs
containing saturated solution of potassium chloride in order to maintain 84% RH.
After 24 hrs the films are to be reweighed and determine the percentage moisture
uptake from the below mentioned formula.
Percentage moisture uptake = [Final weight- Initial weight
6. Water vapour permeability (WVP) evaluation:
Water vapour permeability can be determined with foam dressing method the air
forced oven is replaced by a natural air circulation oven. The WVP can be determined
by the following formula
WVP=W/A
Where, WVP is expressed in gm/m2 per 24hrs,
W is the amount of vapour permeated through the patch expressed in gm/24hrs and A
is the surface area of the exposure samples expressed in m2.
7. Drug content:
A specified area of patch is to be dissolved in a suitable solvent in specific volume.
Then the solution is to be filtered through a filter medium and analyse the drug
contain with the suitable method (UV or HPLC technique). Each value represents
average of three different samples.
86. ADHESION TEST
1 PEELADHESION TEST
BACKING LAYER
ADHESIVE LAYER
The force required to remove an adhesive coating from a test
substrate is referred to as peel adhesion.
The force is expressed in ounces (or grams) per inch width of tape.
If higher value then it indicates greater bond strength.
87.
88. 2. TACK PROPERTY :
2(a) THUMB TACK TEST
Qualitative test.
The thumb is simply pressed on the adhesive and relative tack property is
detected
2(b) ROLLING BALL TACK TEST
2(c) QUICK-STICK (PEEL TEST) TEST
90. 2(d) PROBE TACK TEST
Polyken probe tester
The tip of clean probe is brought into contact with
adhesive, and when a bond is formed between probe
and adhesive. The force required to pull the probe
away from the adhesive at fixed rate is recorded as
tack (Grams).
3 SHEAR STRENGTH TEST
91. Shear strength :
Shear strength is the measurement of the cohesive strength
of an adhesive polymer.
If transdermal device has adequate cohesive strength, it
will not slip after application and will leave no residue upon
removal. In this particular test, adhesive coated tape is
applied onto a stainless steel plate.
A specified weight is hung from the tape to affect its
pulling in a direction parallel to the plate. Shear strength is
determined by measuring the time it takes to pull the tape off
the plate.
The longer the time taken for removal, greater is the shear
strength.
93. Tensile strength
Tensile strength= F/a.b (1+L/l)
F - the force required to break
a - width of film
b - thickness of film
L - length of film
l - elongation of film at break point
94. INVITRO TESTING OF TDDS
SYSTEM DESIGN
SKIN PREPARATION CELL DESIGN
SELECTION
OF SKIN
SEPARATION
Human
Animal
Artificial
Heat
Chemical
Physical
One chambered
(Vertical type)
Two chambered
96. In-vitro testing
Importance
(1)Defining skin permeation kinetic studies using a
diffusion cell system and cadaver skin during the drug
development process.
(2) in vitro drug release kinetics, to be used for batch-to-
batch release and as a compendial test.
2/27/2016 96
97. Preparation of skin for permeation studies
• Intact Full thickness skin
• Separation of epidermis from full thickness
skin:
100. In-vivo assessment
1} Animal model
Mouse, hairless rat, hairless dog, hairless rhesus monkey, rabbit,
guinea pig
101. In-vivo assessment
2} Human model
. Phase I clinical trials are conducted to determine mainly safety in volunteers.
Phase II clinical trials determine short term safety and mainly effectiveness in
patients.
Phase III trials indicate the safety and effectiveness in large number of patient
population.
Phase IV trials at post marketing surveillance are done for marketed patches to
detect adverse drug reactions.
2/27/2016 101
102. Skin irritation studies
• Group I was served as normal, without any
treatment.
• Group II, control, was applied with marketed
adhesive tape.
• Group III Transdermal systems (blank)
• Group IV Transdermal systems (drug loaded)
• Group V standard irritant .
Contact dermatitis
105. Study Storage conditions Time period
Temperature Relative
humidity
Long Term 25°C± 2°C
OR
30°C± 2°C
60%± 5%
OR
65%± 5%
12 months
Intermediate 30°C± 2°C 65%± 5% 6 months
Accelerated 40°C± 2°C 75%± 5% 6 months
106. Table 1 Transdermal Controlled-
Release Products and Devices
Drug Trade Name Type of
Devices
Indication
Scopolamine Transderm-
Scop
Reservoir Motion
sickness
Nitroglycerine Transderm-
Nitro
Reservoir Angina
Nitro-Dur Monolithic
Nitrodisc Monolithic
Estradiol Estraderm Reservoir and
ethanol
enhancer
Hormone
treatment
107. Table 2 transdermal products under
development
Drug Trade name Producer-Marketer
Minocycline Sunstar American Cyanamide,
Takeda
Estradiol+Nore
thisterone
Estracombi
TIS
Ciba-Geigy, Alza
DHEA Pharmedic
Fentanyl
Triamcinolone
acetonide
Whitby Pharm.
109. Products on the market, or in development include:
• Clonidine
• Works as an agonist of adrenaline at the
presynaptic a2 adrenergic
• Product name = Catapres-TTS®
• used to treat hypertension
110. • Ethinylestradiol (EO) and norelgestromin (N)
• Product name = Ortho-Evra®
• Used for Contraception
• Type of patch = Drug-in-Adhesive
• Frequency of application = weekly
111. • Fentanyl
• Product Name = Duragesic®
• Used for: Analgesia
• Type of Patch = Drug-in-Adhesive
• Frequency of Application = Weekly
112. • Lidocaine
• Product Name = Lidoderm®
• Used for: analgesia of postherpetic neuralgia
(PHN), a painful condition caused by the
varicella zoster virus (herpes zoster = shingles)
114. • Nicotine
• Product name = Habitrol®, Nicoderm –
CQ®, Nicotrol®, Prostep®
• Used for: Smoking cessation
• Frequency of administration = Daily
115. • Nitroglycerin
• Works by producing nitric oxide (NO), which then acts as
a vasodilator
• Product Names = Nitro-Dur®, Transderm-Nitro®
• Used for: Angina
• Type of Patch = Nitro-Dur is Drug-in-adhesive
Nitrodisc is reservoir
• Frequency of administration = Daily
116. • Estradiol
• Product Name = Alora®, Climara®, Esclim®,
Estraderm®, FemPatch®, Vivelle®, Vivelle-DOT®
• Used for: Hormone replacement
• Type of Patch: Drug-in-adhesive
• Frequency of application = weekly
117. • Estradiol + Norethindrone
• Product name = CombiPatch®
• Used for: Hormone Replacement
118. • Oxybutynin
• Works as competitive antagonist of the
muscarinic acetycholine receptor
• Product name = Oxytrol®
• Used for: Overactive bladder (antispasmodic)
• Type of Patch: Drug-in-adhesive
• Frequency of application = twice a week
119. • Scopolamine
• Works as competitive antagonist of acetylcholine
at the muscarinic receptor
• Product Name = Transderm Scop®
• Used for: Motion Sickness
121. • Lidocaine + Epinephrine
• Product name = Lidosite
• Used for: Dermal anesthesia
• Type of Patch = Reservoir,
iontophoretic.
Epinephrine acts as vasoconstrictor, thus prolonging the
duration of action of lidocaine (by delaying resorption) at the site
129. The microneedle technology can result in more effective contact of the vaccine
with the antigen-presenting Langerhans cells
The needles can be fabricated to be long enough to penetrate the stratum
corneum, but short enough to not come into contact with nerve endings.
LINK