Pharmacokinetics of Drug_Pharmacology Course_Muhammad Kamal Hossain.pptxMuhammad Kamal Hossain
Pharmacokinetics is defined as the kinetics of drug absorption, distribution, metabolism and excretion (ADME) and their relationship with the pharmacological, therapeutic or toxicological response in man and animals.
Pharmacokinetics of Drug_Pharmacology Course_Muhammad Kamal Hossain.pptxMuhammad Kamal Hossain
Pharmacokinetics is defined as the kinetics of drug absorption, distribution, metabolism and excretion (ADME) and their relationship with the pharmacological, therapeutic or toxicological response in man and animals.
‘Targeted drug delivery system is a special form of drug delivery system where the medicament is selectively targeted or delivered only to its site of action or absorption and not to the non-target organs or tissues or cells.’
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.
Presentation covers the basics of pharmacokinetic. Mechanism for the transport of drug molecule. Absorption, factors affecting on absorption of drugs. Concept of bioavailability. Distribution, plasma protein binding, tissue binding, barriers.
‘Targeted drug delivery system is a special form of drug delivery system where the medicament is selectively targeted or delivered only to its site of action or absorption and not to the non-target organs or tissues or cells.’
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.
Presentation covers the basics of pharmacokinetic. Mechanism for the transport of drug molecule. Absorption, factors affecting on absorption of drugs. Concept of bioavailability. Distribution, plasma protein binding, tissue binding, barriers.
Recomendações da OMS sobre cuidados maternos e neonatais para uma experiência pós-natal positiva.
Em consonância com os ODS – Objetivos do Desenvolvimento Sustentável e a Estratégia Global para a Saúde das Mulheres, Crianças e Adolescentes, e aplicando uma abordagem baseada nos direitos humanos, os esforços de cuidados pós-natais devem expandir-se para além da cobertura e da simples sobrevivência, de modo a incluir cuidados de qualidade.
Estas diretrizes visam melhorar a qualidade dos cuidados pós-natais essenciais e de rotina prestados às mulheres e aos recém-nascidos, com o objetivo final de melhorar a saúde e o bem-estar materno e neonatal.
Uma “experiência pós-natal positiva” é um resultado importante para todas as mulheres que dão à luz e para os seus recém-nascidos, estabelecendo as bases para a melhoria da saúde e do bem-estar a curto e longo prazo. Uma experiência pós-natal positiva é definida como aquela em que as mulheres, pessoas que gestam, os recém-nascidos, os casais, os pais, os cuidadores e as famílias recebem informação consistente, garantia e apoio de profissionais de saúde motivados; e onde um sistema de saúde flexível e com recursos reconheça as necessidades das mulheres e dos bebês e respeite o seu contexto cultural.
Estas diretrizes consolidadas apresentam algumas recomendações novas e já bem fundamentadas sobre cuidados pós-natais de rotina para mulheres e neonatos que recebem cuidados no pós-parto em unidades de saúde ou na comunidade, independentemente dos recursos disponíveis.
É fornecido um conjunto abrangente de recomendações para cuidados durante o período puerperal, com ênfase nos cuidados essenciais que todas as mulheres e recém-nascidos devem receber, e com a devida atenção à qualidade dos cuidados; isto é, a entrega e a experiência do cuidado recebido. Estas diretrizes atualizam e ampliam as recomendações da OMS de 2014 sobre cuidados pós-natais da mãe e do recém-nascido e complementam as atuais diretrizes da OMS sobre a gestão de complicações pós-natais.
O estabelecimento da amamentação e o manejo das principais intercorrências é contemplada.
Recomendamos muito.
Vamos discutir essas recomendações no nosso curso de pós-graduação em Aleitamento no Instituto Ciclos.
Esta publicação só está disponível em inglês até o momento.
Prof. Marcus Renato de Carvalho
www.agostodourado.com
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
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.
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
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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
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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.
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.
The prostate is an exocrine gland of the male mammalian reproductive system
It is a walnut-sized gland that forms part of the male reproductive system and is located in front of the rectum and just below the urinary bladder
Function is to store and secrete a clear, slightly alkaline fluid that constitutes 10-30% of the volume of the seminal fluid that along with the spermatozoa, constitutes semen
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It surrounds the urethra just below the urinary bladder. It has anterior, median, posterior and two lateral lobes
It’s work is regulated by androgens which are responsible for male sex characteristics
Generalised disease of the prostate due to hormonal derangement which leads to non malignant enlargement of the gland (increase in the number of epithelial cells and stromal tissue)to cause compression of the urethra leading to symptoms (LUTS
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.
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2. What is P’cokinetics
▶ how the human body act on the drugs.
▶ Pharmacokinetics is the quantitative study of drug
movement in, through and out of the body.
▶ Intensity of effect is related to concentration of the drug
at the site of action, which depends on its
pharmacokinetic properties
▶ Pharmacokinetic properties of particular drug is important
to determine the route of administration, dose, onset of
action, peak action time, duration of action and
frequency of dosing
5. Membrane transport
▶ Membrane transport is associated with transport
of solute particles across biological membrane
between polar-nonpolar/water soluble-lipid soluble
bilayer.
▶ Regulation of passage through the membrane is due to
selective membrane permeability.
▶ There are different transport proteins are available on the
surface of cells which mediates specific movement across
the bilayer.
▶ these proteins can be activated by cellular signalling
pathways, at the biochemical level,
6. Transport types
▶ Passive transport
1. Diffusion
2. Facilitated diffusion
3. Filtration
4. Osmosis
▶ Active transport
1. Primary active transport
2. Secondary active transport
3. Ponocytosis
9. Remember
▶ The drugs which are Unionized, low polarity and higher lipid solubility are
easy to permeate membrane.
▶ The drugs which are ionized, high polarity and lower lipid solubility are
difficult to permeate membrane.
Filtration
11. Active Transport(energy dependent)
▶ can move solutes against a concentration gradient.
▶ energy dependent
Primary active transport:
• generate energy themselves (e.g. ATP hydrolysis)
Secondary active transporters
• utilize energy stored in voltage and ion gated by a primary active
transporter (e.g. Na+/K+-ATPase)
• Symporters (Co-transporters)
• Antiporters (Exchangers)
13. Pinocytosis
▶ It involves the invagination of a part
of the cell membrane and trapping
within the cell of a small vesicle
containing extra cellular
constituents.
▶ The vesicle contents can than be
released within the cell, or extruded
from the other side of the cell.
▶ Pinocytosis is important for the
transport of some macromolecules
(e.g. insulin through BBB).
16. Absorption
▶ Absorption is the transfer of the unchanged
drug from its site of administration to the
systemic circulation by crossing biological
membrane.
▶ Most of drugs are absorbed by the way of
passive transport.
▶ Intravenous administration has no absorption
because drug is directly reaches to systemic
circulation.
▶ Fraction of administered dose and rate of
absorption are important
18. Drug absorption
▶ If oral-----From stomach and intestine to portal circulation.
▶ If rectal-----from rectum to systemic circulation.
▶ If intramuscular-----from muscle to systemic circulation.
No absorption is needed if drug is taken intravenously.
So absorption is needed to reach the drug to at the site of
action and hence it have to cross the cell membrane.
21. Absorption of drug by passive diffusion
can be explained by Fick’s first law
▶ Rate of diffusion = (C1-C2) 🞩(A🞩PC)
T
Where,
C1- Higher concentration
C2- Lower concentration
A – Diffusion surface area
PC- Permeability coefficient
T – Thickness of membrane
22. Role of route of drug
administration
▶ When a drug is administered intravenously, the
entire dose is available in systemic circulation.
▶ Administration of a drug by any other route may result in less availability of
drug due to incomplete absorption.
▶ When a tablet or capsule is swallowed, it must dissolve before its absorption.
The process is called as dissolution.
▶ Once the drug is dissolve the drug will be absorbed by one of the mechanisms
mentioned earlier.
23. Bioavailability
▶ The rate and extent of absorption of a drug is termed as
its bioavailability.
▶ When a graph of plasma concentration of a drug is plotted
against time, one gets a curve as shown as.
▶ The area under curve (AUC) of plasma concentration versus
time represents the total amount of drug reaching systemic
circulation.
▶ AUC will have a different shape depending on the route of
administration.
▶ AUC obtained after IV administration is consider 100% and is termed
as absolute bioavailability.
▶ The ratio of AUC of any other route of administration is compaited
with AUC of IV administration is termed as relative bioavailability of
that drug.
25. Distribution
▶ Once a drug is absorbed in systemic
circulation, it can be carried throughout the body.
▶ Drug distribution is defined as it is an reversible transfer of drug
between one component(blood) to another component(Extra
vesscular/intera vescular tissue).
▶ Some molecules may be interacting with receptors on cell
membranes or inside of cells, while other molecules may move
back into the blood stream.
27. Significance
▶ Pharmacological action depends upon the concentration of
drug reach to the site of action.
▶ Thus distribution plays important role in
• Onset of action
• Intensity of action
• Duration of action MTC
MEC
28. Distribution depends upon
▶ The delivery of a drug from the blood stream to the site
of drug action depends on…
Blood flow
Capillary permeability
Degree of binding to blood and tissue proteins
Lipid solubility of drug
30. ▶ Blood flow to different organs of the body is not equal.
▶ The most vitally important organs of the body receive the greatest supply of blood.
These organs include the brain, liver, and kidneys.
▶ Skeletal muscle and bone receive less blood, and adipose tissue (fat) receives the
least.
▶ Blood flow is not the only factor responsible for drug distribution penetration
capacity of drug also plays important role in drug distribution
▶ few drugs exhibit good penetration of the central nervous system.
▶ The anatomical structure of the capillary network in the brain creates a significant
barrier to the passage of many drugs and is commonly referred to as the blood-brain
barrier.
▶ To readily penetrate into the brain, drugs must be fairly small and lipid soluble.
▶ This explains why the small and highly fat-soluble anesthetic gases quickly and
easily penetrate the brain to cause anesthesia, while other larger and water
soluble molecules like penicillin antibiotics penetrate the central nervous system
to a much lesser degree.
31. Factors Affecting Distribution
▶ Most drugs reversibly bind to plasma proteins in varying degree. Albumin is
the most abundant plasma protein with an greatest ability to bind drugs.
▶ Binding to plasma proteins affects drug distribution into tissues, because only
drug that is not bound is available to penetrate tissues bind to receptors, and
exert activity.
▶ Albumin acts as a reservoir for administered drug.
▶ Only free fraction of the drug is biologically active.
Free drug + Albumin Penetrate through tissue Bind to receptor Exert effect
Free drug Penetrate through tissue Bind to receptor Exert effect
Release the bloodstreem
Why serum albumin is checked in pathology lab before medication?
32. Factor cont…
▶ Other patient variables that can affect distribution include body composition,
cardiac decompensation (heart failure), and age of the patient.
▶ volume of distribution is the hypothetical volume required if the amount of
drug in the body was distributed throughout the body at the same
concentration measured in the blood.
▶
Dose administered IV
V = Plasma concentration
cardiac decompensation
Failure of the heart to
maintain adequate blood
circulation; symptoms
include shortness of breat
and edema.
Dosing of medications in infants and children requires special consideration. It is to be
noted that “children are not simply small adults” Bodies of children/infants contain a
high percentage of water and low percentage of muscle and fat. Especially in neonates,
albumin may be lower. All these variations can alter Vd significantly; hence dosage for
neonates/infants/children should be carefully adjusted.
33. Metabolism
▶ While the drugs are getting distributed in different parts of body, there are
chemical changes in their structures due to interaction with various enzymes
or due to other chemical reactions.
▶ The process of chemical change is called as biotransformation or metabolism.
▶ Liver is major site for drug metabolism
▶ The purpose of metabolism is to convert the drug into more water soluble
compounds.
▶ The kidneys cannot efficiently excrete highly fat-soluble drugs that readily cross
cell membranes because they are reabsorbed in the last stages of filtration. These
compounds must first be metabolized in the liver to more water-soluble
compounds and then removed.
▶ There are two types of metabolic processes which drugs undergo.
1. oxidation-reduction reactions or hydrolysis.
2. conjugation reactions.
34. oxidation-reduction reactions or hydrolysis.
▶ In the first type of reaction drugs are made more polar through
oxidation-reduction reactions or hydrolysis.
▶ These reactions use metabolic enzymes, most often those of the
cytochrome P450 enzyme system, to catalyze the biotransformation.
▶ In enzyme-catalysed reactions, the rate of reaction is accelerated by
presence of enzymes.
▶ Since the quantum of enzymes is limited, metabolism is considered as a saturable
process.
▶ Once enzymes are saturated, blood levels of drug increase exponentially which may
lead to toxicity.
Ex. metabolism of alcohol or phenytoin.
35. conjugation reactions.
▶ In this type of reaction the drug undergoing change is joined with another substance,
such as glucuronic acid, sulfuric acid, acetic acid, or an amino acid.
▶ Glucuronidation is the most common conjugation reaction.
▶ The result of conjugation is a more water-soluble compound that is easier for the
kidneys to excrete.
▶ Some agents are initially administered as an inactive compound (prodrug) in order to
improve availability or reduce side effects.
Eg. Leodopa/carbidopa – dopamine in the treatment of Parkinson’s disease
36. Factors Affecting Metabolism
1. Genetic factor will result in poor tolerance of certain drugs.
Eg. Many asians and native americans have difficulty metabolizing drugs
that require acetylation, such as ethanol. These individuals will exhibit a
low tolerance of such drugs, and can suffer adverse drug reactions at a
much higher rate than the average population.
▶ Age is another important variable, Organ function gradually declines with
age and the elderly may poorly tolerate to drugs. Also those who are very
young due to immaturity of organs system.
▶ Drug interactions may occur between two drugs that are metabolized by
the same enzyme systems in the liver. Because there is a limit on available
enzymes for metabolism, excess drug will remain active and free to exert
an effect elsewhere in the body.
37. Excretion
▶ When a drug is taken into and distributed throughout the body and is getting
metabolised, there has to be some way by which it is excreted; otherwise its
concentration along with its metabolites will continue to rise with each successive
dose.
▶ The complete removal of drug from the body is termed as its elimination.
▶ Elimination of the drug includes its metabolism and excretion through kidneys and to
a lesser degree into bile.
▶ Excretion in urine is one of the most important mechanisms of drug removal.
▶ When drugs have not been converted to water soluble compounds in the liver, they
are likely to be reabsorbed into blood at the end of filtration process and will cycle
through the body again.
▶ If they are water soluble, they will be excreted in urine.
38. Steady state
Factor affecting on excretion
▶ The complete elimination of a drug from the body is dependent
on normal liver and kidney function.
▶ The kidney is the major organ of excretion in the form of urine
▶ liver also contributes to elimination through metabolism and
excretion into the feces via the bile.
▶ Age is also an important factor in drug excretion in elder persons
kidney and liver function is slightly reduced.