Gastro Retentive Drug Delivery system is a Novel drug delivery system which is more used to retain the drug for a longer period of time in the body and also to increase the GI transit time.
This presentation includes introduction, physiology of GIT, factors affecting GRDDS, Advantages and disadvantages, approaches to GRDDS and their mechanism, some of the marketed products using GRDDS mechanism.
SUSTAINED RELEASE (SR) & CONTROL RELEASE.pptxRAHUL PAL
Sustained-release medications are usually labeled with “SR” at the end of their name. These medications prolong the medication's release from a tablet or capsule so that you'll get the medication's benefits over a longer period of time.
CR = controlled release, SR = sustained release, ER = extended release, IR = immediate release. *
Description about a type of activation modulated drug delivery system, which a type of control drug delivery system.
Also, give a detailed description about each subclassification.
CrDDS is one which delivers the drug at a predetermined rate, for locally or systematically, for a prolong period of time.
DRUG DELIVERY SYSTEM (gastro retentive drug delivery system)
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.
This presentation includes introduction, physiology of GIT, factors affecting GRDDS, Advantages and disadvantages, approaches to GRDDS and their mechanism, some of the marketed products using GRDDS mechanism.
SUSTAINED RELEASE (SR) & CONTROL RELEASE.pptxRAHUL PAL
Sustained-release medications are usually labeled with “SR” at the end of their name. These medications prolong the medication's release from a tablet or capsule so that you'll get the medication's benefits over a longer period of time.
CR = controlled release, SR = sustained release, ER = extended release, IR = immediate release. *
Description about a type of activation modulated drug delivery system, which a type of control drug delivery system.
Also, give a detailed description about each subclassification.
CrDDS is one which delivers the drug at a predetermined rate, for locally or systematically, for a prolong period of time.
DRUG DELIVERY SYSTEM (gastro retentive drug delivery system)
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.
Powerpoint presentation on controlled drug delivery system. Its introduction, terminologies, rationale, advantages, disadvantages, selection of drug, approaches for designing controlled release formulations and physicochemical and biological properties of drug
Osmotic drug delivery uses the osmotic pressure of drug or other solutes (osmogens or osmagents) for controlled delivery of drugs. Osmotic drug delivery has come a long way since Australian physiologists Rose and Nelson developed an implantable pump in 1955.
Powerpoint presentation on controlled drug delivery system. Its introduction, terminologies, rationale, advantages, disadvantages, selection of drug, approaches for designing controlled release formulations and physicochemical and biological properties of drug
Osmotic drug delivery uses the osmotic pressure of drug or other solutes (osmogens or osmagents) for controlled delivery of drugs. Osmotic drug delivery has come a long way since Australian physiologists Rose and Nelson developed an implantable pump in 1955.
Colon-specific drug delivery systems (CDDS) are desirable for the treatment of a range of local diseases such as ulcerative colitis, amebiasis ,irritable bowel syndrome, Crohn’s disease, chronic pancreatitis and colon cancer.
This slides deeply explains about the physiology of stomach and the suitable and non suitable drugs absorbed in stomach and the approaches in the gastrointestinal drug delivery system
In recent years many advancement has been made in research and development of Oral Drug Delivery System. Concept of Novel Drug Delivery System arose to overcome the certain aspect related to physicochemical properties of drug molecule and the related formulations.
Purpose of this review is to compile the recent literature with special focus on Gastro Retentive Drug Delivery Systems to give an update
on pharmaceutical approaches used in enhancing the Gastric Residence Time (GRT). Various approaches are currently used including Gastro Retentive Floating Drug Delivery Systems(GRFDDS),swelling and expanding system, polymeric bioadhesive systems, modifiedshape
systems, high density system and other delayed gastric emptying devices. These systems are very helpful to different problem solve during the formulation of different dosage form. The present work also focuses on the polymers used in floating drug delivery systems
mostly from natural origin. Floating drug delivery systems are less dense than gastric fluids; hence remain buoyant in the upper GIT for a
prolonged period, releasing the drug at the desired/ predeterminedrate. This review article focuses on the recent technological development in floating drug delivery systems with special emphasis on the principal mechanism of floatation and advantages of achieving gastric
retention, brief collection on various polymers employed for floating drug delivery systems etc. In addition this review also summarizes the In –Vitro and In -Vivo studies to evaluate their performance and also their future potential.
Implants- B.Pharm SEM 7- Novel Drug Delivery Systemvedanshu malviya
Implantable drug delivery device classification is not a straightforward task as there are a number of complex implants that will fall into hybrid categories. Nevertheless, implantable drug delivery devices can be broadly classified in two main groups: passive implants and active implants. The first group includes two main types of implants: biodegradable and non-biodegradable implants. On the other hand, active systems rely on energy dependent methods that provide the driving force to control drug release. The second group includes devices such as osmotic pressure gradients and electromechanical drives.
Enzyme Immobilization- Biotechnology- B.Pharm SEM 5vedanshu malviya
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Concept of Health and Diseases- B.Pharm Semester 7vedanshu malviya
health is a state of bodily equilibrium while disease is a state of homeostatic failure. But the process of human growth as Boorse observed is itself leading to homeostatic disequilibrium . Value: disease is undesirable while health is desirable. Health is thus a social value in human society.
Microencapsulation in Novel Drug Delivery Systemvedanshu malviya
Microencapsulation is a process in which tiny particles or droplets are surrounded by a coating to give small capsules, with useful properties. In general, it is used to incorporate food ingredients, enzymes, cells or other materials on a micro metric scale.
Pharmaceutical film coating is considered a key part in the production of solid pharmaceutical dosage forms since it gives superior organoleptic properties products. In addition, it can improve the physical and chemical stability of dosage forms, and modify the release characteristics of the drug. Several troubleshooting problems such as twinning mottling, chipping, etc., may arise during or after or even during the shelf life of the film coated dosage forms. These troubleshooting problems may be due to tablet core faults, coating formulation faults and/or coating process faults. These problems must be overcome to avoid unnecessary product problems. Film coating as well as other parts of the pharmaceutical technology is subjecting to continuous innovation. The innovation may be at different levels including pharmaceutical excipients, processes, software, guidelines and equipment. In fact, of particular note is the growing interest in process analytical technology, quality by design, continuous coating processing and the inclusion of new ready for use coating formulations. In this review, we tried to explore and discuss the status of pharmaceutical film coating, the challenges that face this manufacturing process and the latest technological advances in this important manufacturing process.
The most common tablet manufacturing process techniques are wet granulation, dry granulation, and direct compression.
Your active pharmaceutical ingredients’ (APIs) physical and chemical stability influences manufacturing.
For successful tablet manufacturing, you need granulators, mixing equipment, drying machinery, and coating systems.
Even if you’re using the right equipment to manufacture your product, there is a wide range of common tablet defects that can occur that affect quality.
There are several goals to aim for during the tablet manufacturing process:
Develop tablets that are strong and hard enough to hold up against mechanical shock during manufacturing, packaging, shipping, and dispensing
Formulate tablets that are uniform in weight and drug content
Manufacture bioavailable products according to indication requirements
Create chemically and physically stable tablets that last over long periods
Formulate products that are free of defects and have an elegant finish
Pharmacovigilance supports safe and appropriate use of drugs. Spontaneous reporting of adverse drug reactions (ADRs) is an essential component of pharmacovigilance. However, there is significant underreporting of ADRs. Adverse drug reactions have become a major problem in developing countries. Knowledge of pharmacovigilance could form the basis for interventions aimed at improving reporting rates and decreasing ADRs.
Biopharmaceutics is a scientific discipline that examines the interrelationship of the physicochemical properties of the drug, the dosage form in which the drug is given, and the route of administration on the rate and extent of systemic drug absorption.
Ayurveda, the knowledge of life, immortalized in the form of elegant Sanskrit stanzas in the samhitas describe diagnosis and therapy of disease as well as ways to maintain positive health. Although the technical term “Pharmacovigilance” does not feature in ayurvedic texts, the spirit of pharmacovigilance is vibrant and is emphasized repeatedly in all major texts. The major goals of pharmacovigilance, namely to improve patient care and safety in relation to drug use, and thus promote rational drug use are recurrent themes of ayurvedic pharmacology (dravyaguna vigyan) and therapeutics (chikitsa).
Pharmacokinetics (PK) is the study of how the body interacts with administered substances for the entire duration of exposure (medications for the sake of this article). This is closely related to but distinctly different from pharmacodynamics, which examines the drug’s effect on the body more closely. The four main parameters generally examined by this field include absorption, distribution, metabolism, and excretion (ADME). Wielding an understanding of these processes allows practitioners the flexibility to prescribe and administer medications that will provide the greatest benefit at the lowest risk and allow them to make adjustments as necessary, given the varied physiology and lifestyles of patients.
When a provider prescribes medication, it is with the ultimate goal of a therapeutic outcome while minimizing adverse reactions. A thorough understanding of pharmacokinetics is essential in building treatment plans involving medications. Pharmacokinetics, as a field, attempts to summarize the movement of drugs throughout the body and the actions of the body on the drug. By using the above terms, theories, and equations, practitioners can better estimate the locations and concentrations of a drug in different areas of the body.
The appropriate concentration needed to obtain the desired effect and the amount needed for a higher chance of adverse reactions is determined through laboratory testing. Using the equations given above, a clinician can easily estimate safe medication dosing over a period of time and how long it will take for a medication to leave a patient’s system. These are, however, statistically-based estimations, influenced by differences in the drug dosage form and patient pathophysiology. This is why a deep understanding of these concepts is essential in medical practice so that improvisation is possible when the clinical situation requires it.
Mixing is a general term that includes stirring, beating, blending, binding, creaming, whipping, and folding. In mixing, two or more ingredients are evenly dispersed in one another until they become one product.
The following guideline is a revised version of the ICH Q1A guideline and defines the stability data package for a new drug substance or drug product that is sufficient for a registration application within the three regions of the EC, Japan, and the United States.
What is ICH Q8 guidelines?
Image result for ICH Pharmaceutical development guideline-Q8
The ICH Q8 guideline is intended to provide guidance on the contents of Section 3.2. P. 2 (Pharmaceutical Development) for drug products as defined in the scope of Module 3 of the Common Technical Document (ICH topic M4).
ICH Q7A means the good manufacturing practice guidance for active pharmaceutical ingredients developed under the auspices of the International Conference on Harmonization of Technical Requirements for Registration of Pharmaceuticals for Human Use.
Tablet defects can come from any of the unit operations upstream and from the tablet press. The raw materials may be of poor quality or do not meet specifications, causing excessive fines that lead to a host of defects. The formulation may be the source of defects if the material does not compress well or the processing step specified within the formulation fail to produce a powder with a good flow, compressibility, and ejection properties. The processing and granulation of powder are often the sources of the defect.
Every product behaves differently on a tablet press, even if it‘s the same product run on a different day. The variation often
stems from changes in the properties of the raw materials—active ingredients and excipients- from batch to batch. Naturally,
the goal is to minimize these changes. Tablet press operators, however, don‘t have any control over formulation and
granulation. Tablet specifications are tight, and the list of possible defects is long: Variable weight, sticking, picking, capping, lamination, variable hardness, among others. This article focuses on these variations. It pinpoints the possible causes of these defects and offers advice on preventing and fixing the source of the problems.
The main principle involved in the FBP is the air suspension in which the material to be coated is suspended in the coating material with the help of an air stream. A fluid bed processor (fbp) is a popular material processing technique in different field industries.
The suspension dosage form has long been used for poorly soluble active ingredients for various therapeutic indications. Development of stable suspensions over the shelf life of the drug product continues to be a challenge on many fronts.
Distillation, or classical distillation, is the process of separating the components or substances from a liquid mixture by using selective boiling and condensation. Dry distillation is the heating of solid materials to produce gaseous products. Early evidence of distillation was found on Akkadian tablets dated c. 1200 BCE describing perfumery operations. The tablets provided textual evidence that an early primitive form of distillation was known to the Babylonians of ancient Mesopotamia.[8] Early evidence of distillation was also found related to alchemists working in Alexandria in Roman Egypt in the 1st century CE.
Polymorphism is the ability of solid materials to exist in two or more crystalline forms with different arrangements or conformations of the constituents in the crystal lattice. ... More than 50% of active pharmaceutical ingredients (APIs) are estimated to have more than one polymorphic form
Conductometry is a measurement of electrolytic conductivity to monitor the progress of the chemical reactions. Conductometry has notable application in analytical chemistry, where conductometric titration is a standard technique.
Acute scrotum is a general term referring to an emergency condition affecting the contents or the wall of the scrotum.
There are a number of conditions that present acutely, predominantly with pain and/or swelling
A careful and detailed history and examination, and in some cases, investigations allow differentiation between these diagnoses. A prompt diagnosis is essential as the patient may require urgent surgical intervention
Testicular torsion refers to twisting of the spermatic cord, causing ischaemia of the testicle.
Testicular torsion results from inadequate fixation of the testis to the tunica vaginalis producing ischemia from reduced arterial inflow and venous outflow obstruction.
The prevalence of testicular torsion in adult patients hospitalized with acute scrotal pain is approximately 25 to 50 percent
micro teaching on communication m.sc nursing.pdfAnurag Sharma
Microteaching is a unique model of practice teaching. It is a viable instrument for the. desired change in the teaching behavior or the behavior potential which, in specified types of real. classroom situations, tends to facilitate the achievement of specified types of objectives.
NVBDCP.pptx Nation vector borne disease control programSapna Thakur
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Ozempic: Preoperative Management of Patients on GLP-1 Receptor Agonists Saeid Safari
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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
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.
Prix Galien International 2024 Forum ProgramLevi Shapiro
June 20, 2024, Prix Galien International and Jerusalem Ethics Forum in ROME. Detailed agenda including panels:
- ADVANCES IN CARDIOLOGY: A NEW PARADIGM IS COMING
- WOMEN’S HEALTH: FERTILITY PRESERVATION
- WHAT’S NEW IN THE TREATMENT OF INFECTIOUS,
ONCOLOGICAL AND INFLAMMATORY SKIN DISEASES?
- ARTIFICIAL INTELLIGENCE AND ETHICS
- GENE THERAPY
- BEYOND BORDERS: GLOBAL INITIATIVES FOR DEMOCRATIZING LIFE SCIENCE TECHNOLOGIES AND PROMOTING ACCESS TO HEALTHCARE
- ETHICAL CHALLENGES IN LIFE SCIENCES
- Prix Galien International Awards Ceremony
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.
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1. GRDDS- AN INNOVATIVE AND NOVEL DDS
PREPARED AND PRESENTED BY-
PROF. VEDANSHU R. MALVIYA
P.R.POTE PATIL COLLEGE OF PHARMACY
(Approved by AICTE, PCI-New Delhi & Affiliated to
SGBAU- AMRAVATI)
2. CONTENTS
Introduction
Need for GRDDS
Advantages and Limitations
Ideal Characteristics for GRDDS
Types and Approaches of GRDDS
Marketed Products of GRDDS
Conclusion
References
3. INTRODUCTION
Gastroretentive drug delivery is an approach to
prolong gastric residence time, thereby targeting
site-specific drug release in the upper
gastrointestinal tract (GIT) for local or systemic
effects
Gastro-retentive delivery is one of the site
specific delivery of the drugs at stomach. It is
obtained by retaining dosage form into stomach
and drug is being released at sustained manner
to specific site either in stomach or intestine.
4. NEED FOR GRDDS
Conventional oral drug delivery system (DDS) is
complicated by limited gastric residence time (GRT).
Rapid GI transit can prevent complete drug release in
absorption zone & reduce the efficacy of the
administered dose since the majority of drugs are
absorbed in stomach or the upper part of small intestine.
To overcome these limitations, various approaches have
been proposed to increase gastric residence of drug
delivery systems in the upper part of GIT includes
gastro retentive drug delivery system (GRDDS).
5. ADVANTAGES
Enhanced bioavailability
Sustained drug delivery/reduced frequency of dosing
Targeted therapy for local ailments in the upper GIT
Reduced fluctuations of drug concentration
Improved selectivity in receptor activation
Reduced counter-activity of the body
Extended effective concentration.
Minimized adverse activity at the colon
6. LIMITATIONS
The drug substances that are unstable in the acidic
environment of the stomach are not suitable candidates
to be incorporated in the systems.
These systems require a high level of fluid in the
stomach for drug delivery to float and work efficiently.
Not suitable for drugs that have solubility or stability
problem in GIT.
Drugs which are irritant to gastric mucosa are also not
suitable.
These systems do not offer significant advantages over
the conventional dosage forms for drugs, which are
absorbed throughout GIT.
7. IDEAL CANDIDATES OF DRUG FOR GRDDS
Drugs acting locally in the stomach.
E.g. Antacids and drugs for H. Pylori viz., Misoprostol.
Drugs that are primarily absorbed in the stomach.
E.g. Amoxicillin
Drugs that is poorly soluble at alkaline pH.
E.g. Furosemide, Diazepam, Verapamil, etc.
Drugs with a narrow absorption window.
E.g. Cyclosporine, , Levodopa, Methotrexate etc.
Drugs which are absorbed rapidly from the GI tract.
E.g. Metronidazole, tetracycline.
Drugs that degrade in the colon.
E.g. Ranitidine, Metformin.
Drugs that disturb normal colonic microbes.
E.g. antibiotics against Helicobacter pylori.
9. HIGH DENSITY SYSTEM
Gastric contents have a density close to water ( 1.004
g cm−3). When the patient take high-density pellets ,
they sink to the bottom of the stomach where they
become entrapped in the folds of the antrum and
withstand the peristaltic waves of the stomach wall.
A density close to 2.5 g cm−3 seems necessary for
significant prolongation of gastric residence time.
Barium sulphate , zinc oxide, iron powder, and titanium
dioxide are examples for excipients used.
10. FLOATING DRUG DELIVERY
These have a bulk density lower than the gastric content.
They remain buoyant in the stomach for a prolonged
period of time, with the potential for continuous release
of drug. They Include:
Hydrodynamically balanced systems (HBS)
Gas-generating systems
Volatile liquid/ vacuum containing systems
Raft-forming systems
Low-density systems
11. GAS GENERATING SYSTEMS
Carbonates or bicarbonates, which react with gastric
acid or any other acid (e.g., citric or tartaric) present in
the formulation to produce CO2 , are usually
incorporated in the dosage form, thus reducing the
density of the system and making it float on the media.
12. MATRIX TABLETS
Single layer matrix tablet is prepared by incorporating
bicarbonates in matrix forming hydrocolloid gelling
agent like HPMC, Chitosan, alginate or other polymers
and drug.
Bilayer tablet can also be prepared by gas generating
matrix in one layer and second layer with drug for its SR
effect.
Triple layer tablet also prepared having first swell able
floating layer with bicarbonates, second sustained
release layer of drug and third rapid dissolving layer of
bismuth salt.
13. INFLATABLE GASTROINTESTINAL
DELIVERY
System is incorporated with an inflatable chamber which
contains liquid ether-gasifies at body temperature to
cause the chamber to inflate in stomach.
Inflatable chamber is loaded with a drug reservoir which
can be a drug, impregnated polymeric then
encapsulated in a gelatin capsule.
14. INTRAGASTRIC OSMOTICALLY
CONTROLLED
Comprised of both an osmotic pressure controlled drug delivery
device and an inflatable floating support in a biodegradable capsule.
In stomach, the capsule quickly disintegrates and release the
intragastric osmotically controlled drug delivery device .
Inflatable support forms a deformable hollow polymeric bag
containing liquid that gasifies at body temperature to inflate the bag.
Consists of 2 compartments:
1) Drug reservoir
2) Osmotically active compartment
15. INTRA-GASTRIC FLOATING GASTROINTESTINAL
DRUG DELIVERY SYSTEMS
System can be float by flotation chamber,
which may be vacuum or filled with air or a
harmless gas.
Drug reservoir is encapsulated inside a micro
porous compartment.
16. HYDRODYNAMICALLY BALANCED
SYSYTEMS
Prepared by incorporating a high level (20-75%w/w) gel-
forming hydrocolloids. E.g.:- Hydoxyethylcellulose,
Hydroxypropylcellulose, Pullulan, HPMC & Sod. CMC
into the formulation and then compressing these
granules into a tablets or capsules.
It maintains the bulk density less than 1.
17. RAFT FORMING
This system is used for delivery of antacids and drug
delivery for treatment of gastrointestinal infections and
disorders.
The mechanism involved in this system includes the
formation of a viscous cohesive gel in contact with
gastric fluids, forming a continuous layer called raft.
19. ALGINATE BEADS / SUPERPOROUS
HYDROGELS
ALGINATE BEADS
Prepared by dropping sodium
alginate solution into aqueous
solution of calcium chloride,
causing the precipitation of
calcium alginate
Freeze dry in liquid nitrogen at -
40oc for 24h.
Beads-spherical and 2.5 mm in
diameter.
SUPERPOROUS
HYDROGELS
Swellable agents have pore size
ranging between 10nm to 10µm.
Superporous hydrogels will swell
more than the swelling ratio
100,This is achieved by co-
formulation of a hydrophilic
particulate material, and Ac-Di-
Sol (crosscarmellose).
20. EXPANDABLE SYSTEMS
The swelling is usually results from osmotic absorption
of water.
The device gradually decreases in volume and rigidity as
a result depletion of drug and expanding agent and/or
bioerosion of polymer layer, enabling its elimination.
21. MUCOADHESIVE SYSTEMS
The basis of mucoadhesion is that a dosage form can
stick to the mucosal surface by different mechanisms.
Examples for Materials commonly used for bioadhesion
are poly(acrylic acid) (Carbopol®, polycarbophil),
chitosin, Gantrez® (Polymethyl vinyl ether/maleic
anhydride copolymers), cholestyramine, tragacanth,
sodium alginate, HPMC, Pullulan,etc.
22. MARKETED PRODUCTS OF GRDDS
Brand Name Drug Delivery System Company
Cifran OD ® Ciprofloxacin HCl
(500mg-1000mg)
Gas Generating
Floating System
Sun Pharma, India
Rantac OD ® Ranitidine
(300mg)
Floating System J.B Chemicals,
India
Conviron ® Ferrous sulphate Colloidal gel
forming FDDS
Ranbaxy, India
Dompan SR ® Pantoprazole
(40mg) and
Domperidone
(30mg)
Floating Tablet Medley, India
Creon 10000 ® Pancreatin (10000
units)
Microcapsules Abbot, India
Topalkan® Al – Mg antacid Floating liquid
alginate
Preparation
Pierre Fabre Drug,
France
23. CONCLUSION
Gastro retentive drug delivery systems has proved to be a
novel approach of controlled delivery of drugs that
exhibit an absorption window.
All these drug delivery systems have their own
advantages and drawbacks.
To design a successful GRDDS, it is necessary to take
into consideration the physicochemical properties of the
drug, physiological events in the GIT, formulation
strategies, and correct combination of drug and
excipients.
From this we can concluded that GRDDS can be a better
alternative than other oral drug delivery system having a
retentive drug delivery system
24. REFERENCES
S. P. Vyas, Roop K. Khar, CONTROLLED DRUG
DELIVERY – Concepts & Advances, Vallabh Prakashan,
page no. 196-217.
N K Jain. Gastroretentive drug delivery systems:
Garima Chawla, Piyush Gupta and Aravind K. Bansal,
editors. Progress in controlled and novel drug delivery
systems. New Delhi.
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