Various Physiological barriers as a protective of drug , & their related Bio pharmaceutical action pharmacokinetic action the list of drugs and other relevant details
Biopharmaceutics: Mechanisms of Drug AbsorptionSURYAKANTVERMA2
Biopharmaceutics is defined as the study of factors influencing the rate and amount of drug that reaches the systemic circulation and the use of this information to optimise the therapeutic efficacy of the drug products.
PHARMACOKINETIC MODELS
Drug movement within the body is a complex process. The major objective is therefore to develop a generalized and simple approach to describe, analyse and interpret the data obtained during in vivo drug disposition studies.
The two major approaches in the quantitative study of various kinetic processes of drug disposition in the body are
Model approach, and
Model-independent approach (also called as non-compartmental analysis).
1. Measurement of Bioavailability:
Direct and indirect methods may be used to assess drug bioavailability. The in-vivo bioavailability of a drug product is demonstrated by the rate and extent of drug absorption, as determined by comparison of measured parameters, e.g., concentration of the active drug ingredient in the blood, cumulative urinary excretion rates, or pharmacological effects.
For drug products that are not intended to be absorbed into the bloodstream, bioavailability may be assessed by measurements intended to reflect the rate and extent to which the active ingredient or active moiety becomes available at the site of action.
The design of the bioavailability study depends on the objectives of the study, the ability to analyze the drug (and metabolites) in biological fluids, the pharmacodynamics of the drug substance, the route of drug administration, and the nature of the drug product.
Pharmacokinetic and/or pharmacodynamic parameters as well as clinical observations and in-vitro studies may be used to determine drug bioavailability from a drug product.
1.1. Pharmacokinetic methods:
These are very widely used and based upon the assumption that the pharmacokinetic profile reflects the therapeutic effectiveness of a drug. Thus these are indirect methods. The two major pharmacokinetic methods are:
The major pharmacokinetic methods are:
Plasma / blood level time profile.
o Time for peak plasma (blood) concentration (t max)
o Peak plasma drug concentration (Cmax)
o Area under the plasma drug concentration–time curve (AUC)
Urinary excretion studies.
o Cumulative amount of drug excreted in the urine (Du)
o Rate of drug excretion in the urine (dDu/dt)
o Time for maximum urinary excretion (t)
C. Other biological fluids
1.2. Pharmacodynamic methods:
IT involves direct measurement of drug effect on a (patho) physiological process as a function of time. Disadvantages of it may be high variability, difficult to measure, limited choices, less reliable, more subjective, drug response influenced by several physiological & environmental factors.
They involve determination of bioavailability from:
Acute pharmacological response.
Therapeutic response.
1.3. In-vitro dissolution studies
Closed compartment apparatus
Open compartment apparatus
Dialysis systems.
1.4. Clinical observations
Well-controlled clinical trials
Biopharmaceutics: Mechanisms of Drug AbsorptionSURYAKANTVERMA2
Biopharmaceutics is defined as the study of factors influencing the rate and amount of drug that reaches the systemic circulation and the use of this information to optimise the therapeutic efficacy of the drug products.
PHARMACOKINETIC MODELS
Drug movement within the body is a complex process. The major objective is therefore to develop a generalized and simple approach to describe, analyse and interpret the data obtained during in vivo drug disposition studies.
The two major approaches in the quantitative study of various kinetic processes of drug disposition in the body are
Model approach, and
Model-independent approach (also called as non-compartmental analysis).
1. Measurement of Bioavailability:
Direct and indirect methods may be used to assess drug bioavailability. The in-vivo bioavailability of a drug product is demonstrated by the rate and extent of drug absorption, as determined by comparison of measured parameters, e.g., concentration of the active drug ingredient in the blood, cumulative urinary excretion rates, or pharmacological effects.
For drug products that are not intended to be absorbed into the bloodstream, bioavailability may be assessed by measurements intended to reflect the rate and extent to which the active ingredient or active moiety becomes available at the site of action.
The design of the bioavailability study depends on the objectives of the study, the ability to analyze the drug (and metabolites) in biological fluids, the pharmacodynamics of the drug substance, the route of drug administration, and the nature of the drug product.
Pharmacokinetic and/or pharmacodynamic parameters as well as clinical observations and in-vitro studies may be used to determine drug bioavailability from a drug product.
1.1. Pharmacokinetic methods:
These are very widely used and based upon the assumption that the pharmacokinetic profile reflects the therapeutic effectiveness of a drug. Thus these are indirect methods. The two major pharmacokinetic methods are:
The major pharmacokinetic methods are:
Plasma / blood level time profile.
o Time for peak plasma (blood) concentration (t max)
o Peak plasma drug concentration (Cmax)
o Area under the plasma drug concentration–time curve (AUC)
Urinary excretion studies.
o Cumulative amount of drug excreted in the urine (Du)
o Rate of drug excretion in the urine (dDu/dt)
o Time for maximum urinary excretion (t)
C. Other biological fluids
1.2. Pharmacodynamic methods:
IT involves direct measurement of drug effect on a (patho) physiological process as a function of time. Disadvantages of it may be high variability, difficult to measure, limited choices, less reliable, more subjective, drug response influenced by several physiological & environmental factors.
They involve determination of bioavailability from:
Acute pharmacological response.
Therapeutic response.
1.3. In-vitro dissolution studies
Closed compartment apparatus
Open compartment apparatus
Dialysis systems.
1.4. Clinical observations
Well-controlled clinical trials
Barriers of Communication,Types of Barriers in Communication,1.Physical barriers,2.Physiological barriers,Example for psychological,PSYCHOLOGICAL BARRIERS,Selective perception,Message related barrier,4.Organizational barrier,Organizational barriers,Cross-cultural barrier,Different languages And cultures,Learning about other cultures,Discrimination,Dealing with Discrimination in the Workplace,Types Of Discrimination,Overcoming barriers,Personal barriers,Barriers related to the communicator
Barriers of Communication,Types of Barriers in Communication,1.Physical barriers,2.Physiological barriers,Example for psychological,PSYCHOLOGICAL BARRIERS,Selective perception,Message related barrier,4.Organizational barrier,Organizational barriers,Cross-cultural barrier,Different languages And cultures,Learning about other cultures,Discrimination,Dealing with Discrimination in the Workplace,Types Of Discrimination,Overcoming barriers,Personal barriers,Barriers related to the communicator
TSDP tells about the essential documents that are required for the #conduct of a clinical trial. For #regulatory medical writing training, contact hello@turacoz.in.
The presentation on ICHGCP guidelines overview.The presentation gives a detailed view of What is ICHGCP, Principles of ICH & GCP
IRB & IEC, Investigator, Sponsor, Clinical trial Protocol
Investigator brochures & Essential documents.
Describes the plasma membrane in detail, explains the each major component with its functions.
Transport mechanism across the cell is covered with detailed explanation with examples.
by Dr. N.Sivaranjani, MD
Physiological barriers to diffusion of drugsLokesh Patil
Drug distribution is greatly hampered by physiological barriers to drug diffusion, including cell membranes, the blood-brain barrier (BBB), blood-testis barrier (BTB), placental barrier, gastrointestinal tract barrier, and mucosal barrier. Whereas the BBB prevents most medications from reaching the central nervous system, cell membranes preferentially allow lipophilic medications to pass. The testes and fetus are similarly denied medication access by the placental barrier and the BTB, respectively. Through different pH levels and first-pass metabolism, the GI tract barrier influences medication absorption; mucosal barriers trap compounds in mucus and expose them to enzymatic breakdown. To improve medication penetration and effectiveness, these obstacles are overcome by means of techniques including chemical changes, nanoparticle formulations, and direct delivery techniques.
1. Distribution of drug
2. Factor affecting of drug
3. Protein binding of drug
4. Factors affecting of protein binding of drug
5. Significance of protein drug binding
6. Volume of distribution
What Is Disposition?
What Is Distribution?
Steps In Drug Distribution
Factors Affecting Distribution Of Drugs
Physiological Barriers To Distribution
Volume Of Distribution
Specific Tracers Or Markers
Methods For Studying Drug Distribution Pattern
D M Brahmankar and Sunil B.Jaiswal Biopharmaceutics and Pharmacokinetics A Treatise
Drug distibution, significance, steps in Drug distribution, Factors affecting,physiochemical properties of drug, volume of distribution,protein binding, mechanism of protein drug binding
Synthetic Fiber Construction in lab .pptxPavel ( NSTU)
Synthetic fiber production is a fascinating and complex field that blends chemistry, engineering, and environmental science. By understanding these aspects, students can gain a comprehensive view of synthetic fiber production, its impact on society and the environment, and the potential for future innovations. Synthetic fibers play a crucial role in modern society, impacting various aspects of daily life, industry, and the environment. ynthetic fibers are integral to modern life, offering a range of benefits from cost-effectiveness and versatility to innovative applications and performance characteristics. While they pose environmental challenges, ongoing research and development aim to create more sustainable and eco-friendly alternatives. Understanding the importance of synthetic fibers helps in appreciating their role in the economy, industry, and daily life, while also emphasizing the need for sustainable practices and innovation.
How to Make a Field invisible in Odoo 17Celine George
It is possible to hide or invisible some fields in odoo. Commonly using “invisible” attribute in the field definition to invisible the fields. This slide will show how to make a field invisible in odoo 17.
How to Split Bills in the Odoo 17 POS ModuleCeline George
Bills have a main role in point of sale procedure. It will help to track sales, handling payments and giving receipts to customers. Bill splitting also has an important role in POS. For example, If some friends come together for dinner and if they want to divide the bill then it is possible by POS bill splitting. This slide will show how to split bills in odoo 17 POS.
The French Revolution, which began in 1789, was a period of radical social and political upheaval in France. It marked the decline of absolute monarchies, the rise of secular and democratic republics, and the eventual rise of Napoleon Bonaparte. This revolutionary period is crucial in understanding the transition from feudalism to modernity in Europe.
For more information, visit-www.vavaclasses.com
Ethnobotany and Ethnopharmacology:
Ethnobotany in herbal drug evaluation,
Impact of Ethnobotany in traditional medicine,
New development in herbals,
Bio-prospecting tools for drug discovery,
Role of Ethnopharmacology in drug evaluation,
Reverse Pharmacology.
We all have good and bad thoughts from time to time and situation to situation. We are bombarded daily with spiraling thoughts(both negative and positive) creating all-consuming feel , making us difficult to manage with associated suffering. Good thoughts are like our Mob Signal (Positive thought) amidst noise(negative thought) in the atmosphere. Negative thoughts like noise outweigh positive thoughts. These thoughts often create unwanted confusion, trouble, stress and frustration in our mind as well as chaos in our physical world. Negative thoughts are also known as “distorted thinking”.
2024.06.01 Introducing a competency framework for languag learning materials ...Sandy Millin
http://sandymillin.wordpress.com/iateflwebinar2024
Published classroom materials form the basis of syllabuses, drive teacher professional development, and have a potentially huge influence on learners, teachers and education systems. All teachers also create their own materials, whether a few sentences on a blackboard, a highly-structured fully-realised online course, or anything in between. Despite this, the knowledge and skills needed to create effective language learning materials are rarely part of teacher training, and are mostly learnt by trial and error.
Knowledge and skills frameworks, generally called competency frameworks, for ELT teachers, trainers and managers have existed for a few years now. However, until I created one for my MA dissertation, there wasn’t one drawing together what we need to know and do to be able to effectively produce language learning materials.
This webinar will introduce you to my framework, highlighting the key competencies I identified from my research. It will also show how anybody involved in language teaching (any language, not just English!), teacher training, managing schools or developing language learning materials can benefit from using the framework.
3. PHYSIOLOGICAL BARRIER
• A membrane (or a barrier) with special structural feature can be a permeability
restriction to distribution of drugs to some tissue .
Physiological Barrier
4. TYPES OF PHYSIOLOGICAL
BARRIER
• The Important simple & specialized physiological barriers are--
• a. Simple Capillary endothelial Barrier
• b. Simple cell membrane Barrier
• c. Blood -Brain Barrier
• d.Blood- CSF Barrier
• e.Blood-Placental Barrier
• f.Blood-Testis Barrier
5. • The membrane of capillaries that supply blood to most tissues is not a barrier to
moieties , or drugs ..thus all drugs ionised or unionised , with a molecular size(MW)
less than 600 Dalton , diffuse through the capillary endothelium and into the
interstitial fluid .
6. Simple cell Membrane Barrier
• once a drug diffuses from the capillary wall into the extracellular fluid , its further entry into cells of
most tissues is limited by its permeability through the membrane that lines such cells , such a
simple cell membrane is similar to the lipoiidal barrier in the GI absorption of drugs .
7. • The capillaries in the brain are highly specialized & much less permeable to water
soluble drugs . The brain capillaries consist of endothelial cells which are joined to
one another by continuous tight intercellular junctions comprising what is called as
the blood brain barrier. Moreover the presence of special cells called astrocytes &
pericytes .
8. • A solute may thus gain access to brain via only of the two pathway ,.
• Passive diffusion through the lipoidal barrier : which is restricted to small molecules (with a MW less
that a threshold of approx 700 Da ) having high o/w partition coefficient
• Active transport of essential nutrients such as sugars and amino acids . Thus structurally similar
foreign molecules can also penetrate the BBB by the same mechanism .
• List of drugs that can cross BBB-
Name of the Drug Solubility Used as
Levodopa Water (66mg/ml) Anti Parkinsons disease
Carbidopa Water (3.8 mg/ml) Anti Parkinsons disease
Sulphadiazine Ethanol , Methanol
acetone
Meningitis
Carmustine Alcohol, poorly soluble
in water
Brain Tumour
Lomustine Polar solvents Brain Circinoma
9. BLOOD BRAIN BARRIER AS A DRUG PROTECTIVE
• The 3 different approaches are …
• 1) Use of permeation enhancers such as dimethyl sulphoxide (DMSO)
• 2.)Osmotic disruption of the BBB by infusion internal carotid artery with mannitol
• 3.)Use of dihydropyridine Redox system as durg carriers to the brain
• In the latter case , the lipid soluble dihydropyridine is linked as a carrier to the polar drug to
form a prodrug that readily crosses the BBB.
10. • The cerebrospinal fluid(CSF) is formed mainly by the choroid plexus of the lateral
third & fourth ventricles & is similar in composition to the ECF of brain The capillary
endothelium that lines the choroid plexus have open junctions or gaps and drugs
can flow freely into the extracellular space between the capillary wall and the
choroidal cells.
11. BLOOD –CSF BARRIER AS A
DRUG PROTECTIVE
• As in the case of BBB only highly lipid soluble drugs can cross the blood CSF barrier with relative case whereas
moderately lipid soluble and partially ionised drugs permeate slowly. A drug that enters the CSF slowly can’t achieve
a high concentration as the bulk flow of CSF continuously removes the drug .for any given drug its concentration in
the brain will always be higher than in the CSF .
• List of drugs that are permeable through the Blood –CSF Barrier are-
Name of the Drug Solubility Used as
Sulphamethoxazole Dimethyl sulphoxide
(51mg/ml)
Sulphonamide Antibiotic
Trimethoprim Water (0.4mg/ml),
ethanol(2.6mg/ml at 20°
C)
Di hydro folate reductase
inhibitor
Ofloxacin Water 28.3 mg/ml Eye Infection
Timolol water (15mg/ml) Glucoma
Esmolol Water & very soluble in
HCL
PSVT(Paroxymal supra
ventricular tachycardia)
Labetolol Water (117 mg/ml ) Anti Hypertensive
12. BLOOD PLACENTAL BARRIER
• The maternal and the fetal blood vessels are separated by a number of tissue
layers made of fetal trophoblast basement membrane and the endothelium which
together constitute the placental barrier the flow of blood in the maternal and the
fetal blood vessels is shown in the figure
13. PLACENTAL BARRIER AS A
DRUG PROTECTIVE
• The human placental barrier has a mean thickness of 25 microns in early pregnancy that reduces to 2 micron at full
term which however does not reduce its effectiveness. Many drugs having molecular weight less than 1000 Da &
moderated to high lipid solubility that is Ethanol Sulphonamides Barbiturates gaseous anaesthetics steroids
narcotic analgesics anti convulsants and some antibiotics
• An agent that cause toxic effects on fetus is called as TERATOGEN.
• TERATOGENECITY is defined as fetal abnormalities caused by administration of drugs during pregnancy
• Drugs can affect the fetus at 3 stages as shown in the underneath table
Period Significance Harazdous Effects
First 2 weeks Fertilization and implantation stage Miscarriage
2-8 weeks Period of organogenesis Cleft palate, optic atrophy, mental
retardation ,neural tube defects etc
8weeks onwards Growth and development Development and functional
abnormalities
14. • This barrier is located not at the capillary endothelium level but at sertoli-sertoli cell
junction . It is the tight junction between the neighbouring sertoli cells that act as the
blood-testis barrier . This barrier restricts the passage of drugs to spermatocytes
and spermatids …
15. Name Solubility Related Physiological Barrier Used as
Levodopa Water (66mg/ml) Blood Brain Barrier Anti Parkinsons disease
Fluconazole Water (8-10 mg/ml) Simple cell membrane barrier Anti Fungal
Silver Sulphadiazine Ethanol , Methanol acetone Simple capillary endothelium
barrier
Burn Therapy
Carmustine Alcohol, poorly soluble in water Blood Brain Barrier Brain Tumour
Sulphamethoxazole Dimethyl sulphoxide (51mg/ml) Blood CSF barrier Sulphonamide Antibiotic
Doxorubicin Water (10mg/ml) Blood Testis Barrier Prostate cancer
Ofloxacin Water 28.3 mg/ml Blood CSF Barrier Eye Infection
Cisplatin dissolve 250mg inside a sigma flask in
41,655ml of PBS to make a solution of
20mM
Blood Placental Barrier Ovarian Carcinoma
16. References
• D.M Brahmankar & Sunil B Jaiswal; Biopharmaceutics and
Pharmacokinetics –A Treatise; 3rd Edn ,111-114.
• Anil Baran Singha Mahapatra ; Essential of Medical Physiology ; Current
Books International , Kolkata : 4th Edn , 2014; 256 , 392,370,383.
• Dickerson & Vascan ; Physiological Barriers ; University Of Chicago,
United States Of America ; The Journal of physiology; 31990; 429: 10-46.