1) The document discusses several key concepts in pharmacology including bioavailability, bioequivalence, therapeutic index, plasma half-life, dose response curves, area under the curve, and volume of distribution. Definitions and examples are provided for each topic.
2) Bioavailability refers to the fraction of an administered dose that reaches systemic circulation. Bioequivalence exists between two drug preparations that have similar bioavailability. Therapeutic index represents the safety of a drug based on the difference between toxic and therapeutic concentrations.
3) Plasma half-life is the time for a drug concentration to reduce by half, and is determined by clearance and volume of distribution. Dose response curves relate the effect of varying
General pharmacology and pharmocokineticsSwapnil Singh
Basic pharmacology and Pharmacokinetics principles and concepts covering routes of drug administration, absorption phenomena, metabolism and excretion from the body.
General pharmacology and pharmocokineticsSwapnil Singh
Basic pharmacology and Pharmacokinetics principles and concepts covering routes of drug administration, absorption phenomena, metabolism and excretion from the body.
The slides describe concept of distribution, Volume of distribution, factors affecting volume of distribution and the barriers to distribution. Blood brain barrier and placental barrier.
Factors affecting each of the proceses- Absorption, Distribution, Metabolism and Elimination of Drugs and associated Pharmacokinetic Parameters- Bioavailability, Volume of Distribution, Half life of drug, Rate of Clearance
CONCEPT OF LOADING AND MAINTAINANCE DOSE.pptxNamrataSawant19
Most drugs for chronic condition are prescribed in a dosage regimen is based on the administration of a fixed constant dose(D) at fixed regular dosing intervals(T) for long period of time.
The D & T recommended by the manufacturer is based on the effective therapeutic concentration of drug in the plasma needed to treat the chronic condition.
Primary purpose of using loading dose in therapeutic treatment is to attain steady-state concentration of the drug as quickly as possible, usually right from the start of the dosage regimen for the treatment.
The slides describe concept of distribution, Volume of distribution, factors affecting volume of distribution and the barriers to distribution. Blood brain barrier and placental barrier.
Factors affecting each of the proceses- Absorption, Distribution, Metabolism and Elimination of Drugs and associated Pharmacokinetic Parameters- Bioavailability, Volume of Distribution, Half life of drug, Rate of Clearance
CONCEPT OF LOADING AND MAINTAINANCE DOSE.pptxNamrataSawant19
Most drugs for chronic condition are prescribed in a dosage regimen is based on the administration of a fixed constant dose(D) at fixed regular dosing intervals(T) for long period of time.
The D & T recommended by the manufacturer is based on the effective therapeutic concentration of drug in the plasma needed to treat the chronic condition.
Primary purpose of using loading dose in therapeutic treatment is to attain steady-state concentration of the drug as quickly as possible, usually right from the start of the dosage regimen for the treatment.
Perfect Exposure
Understanding Light
Composition
Do you want to take your photography skills to the next level, this one day Digital Photography workshop is designed for you. The more you know about how your camera works the better photographer you are going to be. When you learn to truly understand how aperture, shutter speed, ISO, depth of field, composition and light work together, you open up a new way to see the world and create powerful imagery..
Take creative control of your camera and have more fun with photography
A guide to exposure determination and the impact of artworkWilliam Shorter
An overview of how exposure and the artwork process can affect the durability and the quality of the image that you are printing. Presented by William Shorter.
A well designed toxicokinetic study may involve several different strategies and depends on the scientific question to be answered. Controlled acute and repeated toxicokinetic animal studies are useful to identify a chemical's biological persistence, tissue and whole body half-life, and its potential to bioaccumulate. Toxicokinetic profiles can change with increasing exposure duration or dose. Real world environmental exposures generally occur as low level mixtures, such as from air, water, food, or tobacco products. Mixture effects may differ from individual chemical toxicokinetic profiles because of chemical interactions, synergistic, or competitive processes. For other reasons, it is equally important to characterize the toxicokinetics of individual chemicals constituents found in mixtures as information on behavior or fate of the individual chemical can help explain environmental, human, and wildlife biomonitoring studies.
Introduction to pharmacokinetics and pharmacodynamics drug interactionRuchiRawat13
drug interaction, definition of- drug interaction, pharacokinetics, pharmacodynamis and various types of drug interaction and factors affecting drug interaction, including identification of drug interaction. software and analytical technique to find out drug interaction. examples of drug-drug interaction and the result of interaction
Pharmacotherapeutics is specially for the utilization of medicines in the treatment of diseases, conditions and symptoms. This Pharmacotherapeutics presentation basically contains about the introduction to pharmacotherapeutics, its scope and objectives.
Toxicology deals with the study of the harmful effects of chemicals on living beings. This branch of science has been equally recognised in medical as well as scientific field
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Magnetically Modulated drug delivery system, Noval Drug Delivery system, New approaches to develop magnetically modulated drug delivery system and Formulation Design.
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.
Tom Selleck Health: A Comprehensive Look at the Iconic Actor’s Wellness Journeygreendigital
Tom Selleck, an enduring figure in Hollywood. has captivated audiences for decades with his rugged charm, iconic moustache. and memorable roles in television and film. From his breakout role as Thomas Magnum in Magnum P.I. to his current portrayal of Frank Reagan in Blue Bloods. Selleck's career has spanned over 50 years. But beyond his professional achievements. fans have often been curious about Tom Selleck Health. especially as he has aged in the public eye.
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Introduction
Many have been interested in Tom Selleck health. not only because of his enduring presence on screen but also because of the challenges. and lifestyle choices he has faced and made over the years. This article delves into the various aspects of Tom Selleck health. exploring his fitness regimen, diet, mental health. and the challenges he has encountered as he ages. We'll look at how he maintains his well-being. the health issues he has faced, and his approach to ageing .
Early Life and Career
Childhood and Athletic Beginnings
Tom Selleck was born on January 29, 1945, in Detroit, Michigan, and grew up in Sherman Oaks, California. From an early age, he was involved in sports, particularly basketball. which played a significant role in his physical development. His athletic pursuits continued into college. where he attended the University of Southern California (USC) on a basketball scholarship. This early involvement in sports laid a strong foundation for his physical health and disciplined lifestyle.
Transition to Acting
Selleck's transition from an athlete to an actor came with its physical demands. His first significant role in "Magnum P.I." required him to perform various stunts and maintain a fit appearance. This role, which he played from 1980 to 1988. necessitated a rigorous fitness routine to meet the show's demands. setting the stage for his long-term commitment to health and wellness.
Fitness Regimen
Workout Routine
Tom Selleck health and fitness regimen has evolved. adapting to his changing roles and age. During his "Magnum, P.I." days. Selleck's workouts were intense and focused on building and maintaining muscle mass. His routine included weightlifting, cardiovascular exercises. and specific training for the stunts he performed on the show.
Selleck adjusted his fitness routine as he aged to suit his body's needs. Today, his workouts focus on maintaining flexibility, strength, and cardiovascular health. He incorporates low-impact exercises such as swimming, walking, and light weightlifting. This balanced approach helps him stay fit without putting undue strain on his joints and muscles.
Importance of Flexibility and Mobility
In recent years, Selleck has emphasized the importance of flexibility and mobility in his fitness regimen. Understanding the natural decline in muscle mass and joint flexibility with age. he includes stretching and yoga in his routine. These practices help prevent injuries, improve posture, and maintain mobilit
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
NVBDCP.pptx Nation vector borne disease control programSapna Thakur
NVBDCP was launched in 2003-2004 . Vector-Borne Disease: Disease that results from an infection transmitted to humans and other animals by blood-feeding arthropods, such as mosquitoes, ticks, and fleas. Examples of vector-borne diseases include Dengue fever, West Nile Virus, Lyme disease, and malaria.
Ozempic: Preoperative Management of Patients on GLP-1 Receptor Agonists Saeid Safari
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ASA GUIDELINE
NYSORA Guideline
2 Case Reports of Gastric Ultrasound
CDSCO and Phamacovigilance {Regulatory body in India}NEHA GUPTA
The Central Drugs Standard Control Organization (CDSCO) is India's national regulatory body for pharmaceuticals and medical devices. Operating under the Directorate General of Health Services, Ministry of Health & Family Welfare, Government of India, the CDSCO is responsible for approving new drugs, conducting clinical trials, setting standards for drugs, controlling the quality of imported drugs, and coordinating the activities of State Drug Control Organizations by providing expert advice.
Pharmacovigilance, on the other hand, is the science and activities related to the detection, assessment, understanding, and prevention of adverse effects or any other drug-related problems. The primary aim of pharmacovigilance is to ensure the safety and efficacy of medicines, thereby protecting public health.
In India, pharmacovigilance activities are monitored by the Pharmacovigilance Programme of India (PvPI), which works closely with CDSCO to collect, analyze, and act upon data regarding adverse drug reactions (ADRs). Together, they play a critical role in ensuring that the benefits of drugs outweigh their risks, maintaining high standards of patient safety, and promoting the rational use of medicines.
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.
Adv. biopharm. APPLICATION OF PHARMACOKINETICS : TARGETED DRUG DELIVERY SYSTEMSAkankshaAshtankar
MIP 201T & MPH 202T
ADVANCED BIOPHARMACEUTICS & PHARMACOKINETICS : UNIT 5
APPLICATION OF PHARMACOKINETICS : TARGETED DRUG DELIVERY SYSTEMS By - AKANKSHA ASHTANKAR
Basavarajeeyam is an important text for ayurvedic physician belonging to andhra pradehs. It is a popular compendium in various parts of our country as well as in andhra pradesh. The content of the text was presented in sanskrit and telugu language (Bilingual). One of the most famous book in ayurvedic pharmaceutics and therapeutics. This book contains 25 chapters called as prakaranas. Many rasaoushadis were explained, pioneer of dhatu druti, nadi pareeksha, mutra pareeksha etc. Belongs to the period of 15-16 century. New diseases like upadamsha, phiranga rogas are explained.
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TOPIC
1) Bioavailability
2) Bioequivalence
3) Therapeutic index
4) Plasma half life
5) Dose response curve
6) Area under curve (AUC)
7) Volume of distribution
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PHARMACOKINETICS
Pharmakon ( drug )
Kinetics ( motion )
Definition : The actions of the body on an
administered drug ( dose concentration ).
It involves drug absorption ,
distribution , metabolism and elimination .
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Pharmacokinetics
conc. vs time
Conc.(mg/L)
0.0
0 25
Time (h)
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1) BIOAVAILABILITY
In pharmacology, bioavailability is a measurement of the rate and extent to
which a drug reaches the systemic circulation It is denoted by the letter f
Bioavailability is the ratio of the area calculated for oral route of
administration to the intravenous route of administration.
In pharmacology, bioavailability (BA) is a subcategory of absorption and is
the fraction of an administered dose of unchanged drug that reaches
the systemic circulation, one of the principal pharmacokinetic properties
of drugs. By definition, when a medication is administered intravenously, its
bioavailability is 100%.
However, when a medication is administered via other routes (such as
orally), its bioavailability generally decreases (due to incomplete absorption
and first-pass metabolism) or may vary from patient to patient.
Bioavailability is one of the essential tools in pharmacokinetics, as
bioavailability must be considered when calculating dosages for non-
intravenous routes of administration.
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For a non-intravenous drug , it is less than
100% because of :
1) Absorption Parameters.
2)First-pass elimination.
Bioavailability is the drug proportion that
actually reaches systemic circulation .
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2) BIOEQUIVALENCE
Relationship between 2 preparations of the
same drug at same dose in same form with
similar bioavailability.
OR
The relationship between two preparations of
the same drug in the same dosage form that
have a similar bioavailability.
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Bioequivalence is a term in pharmacokinetics used to assess the
expected in vivo biological equivalence of two proprietary
preparations of a drug. If two products are said to be bioequivalent it
means that they would be expected to be, for all intents and
purposes, the same.
two pharmaceutical products are bioequivalent if they are
pharmaceutically equivalent and their bioavailabilities (rate and
extent of availability) after administration in the same molar dose are
similar to such a degree that their effects, with respect to both
efficacy and safety, can be expected to be essentially the same.
Pharmaceutical equivalence implies the same amount of the same
active substance(s), in the same dosage form, for the same route of
administration and meeting the same or comparable standards."[1]
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3) THERAPEUTIC INDEX
The difference between the minimum
therapeutic and minimum toxic
concentrations of a drug.
Therapeutic index represents the safety of
a drug.
Drugs having low therapeutic index include:
Anticonvulsants, lithium, anticoagulants,
corticosteroids and cardio active drugs.
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therapeutic index (also known as therapeutic ratio)
is a comparison of the amount of a therapeutic agent
that causes the therapeutic effect to the amount that
causes death (in animal studies) or toxicity (in human
studies).
the ratio between the dosage of a drug that causes a
lethal effect and the dosage that causes therapeutic
effect.
Medical Dictionary :
The ratio between the toxic dose and the therapeutic
dose of a drug, used as a measure of the relative
safety of the drug for a particular treatment.
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4) PLASMA HALF LIFE
The duration of action of a drug is known as its half life.
This is the period of time required for the concentration or amount of
drug in the body to be reduced by one-half.
Drug can be eliminated from the body, or it can be translocated to
another body fluid compartment such as the intracellular fluid or it can
be destroyed in the blood after it is reduced to half life.
The removal of a drug from the plasma is known as clearance and the
distribution of the drug in the various body tissues is known as
the volume of distribution. Both of these pharmacokinetic parameters
are important in determining the half life of a drug.
Here is the symbol to represent the half-life: t½
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The biological half-life or elimination half-
life of a substance is the time it takes for a
substance (for example
a metabolite, drug, signaling molecule,
radioactive nuclide, or other substance) to lose
half of its pharmacologic, physiologic, or
radiologic activity , as per the MeSH definition.
Biological half-life is an
important pharmacokinetic parameter .
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5) DOSE-RESPONSE CURVE
A dose–response curve is a simple X–Y graph relating the magnitude of a stressor ( e.g.
amount of drug ) to the response of receptor.
The measured dose (usually in milligrams, micrograms, or grams per kilogram of body-
weight for oral exposures or milligrams per cubic meter of ambient air for inhalation
exposures) is generally plotted on the X axis and the response is plotted on the Y axis.
The dose–response relationship , describes the change in effect on an organism caused
by differing levels of exposure (or doses) to a stressor (usually a chemical) after a certain
exposure time.[1] This may apply to individuals (e.g.: a small amount has no significant
effect, a large amount is fatal), or to populations (e.g.: how many people or organisms are
affected at different levels of exposure).
Studying dose response, and developing dose response models, is central to determining
"safe" and "hazardous" levels and dosages for drugs, potential pollutants, and other
substances to which humans or other organisms are exposed. These conclusions are often
the basis for public policy.
Dose–response relationships generally depend on the exposure time and exposure route
(e.g., inhalation, dietary intake); quantifying the response after a different exposure time or
for a different route leads to a different relationship and possibly different conclusions on
the effects of the stressor under consideration.
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6) AREA UNDER CURVE (AUC)
The area under the plot of plasma concentration
of drug (not logarithm of the concentration)
against time after drug administration
The area under the plasma (serum, or blood)
concentration versus time curve (AUC) has a
number of important uses in pharmacokinetics.
The AUC is of particular use in estimating
bioavailability of drugs, and in estimating total
clearance of drugs (ClT).
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AUC can be used as a measure of drug exposure. It is
derived from drug concentration and time so it gives a
measure how much - how long a drug stays in a body.
The AUC measured after administration of a drug product
is an important parameter in the comparison of drug
products. These bioequivalence or bioavailability
studies can be analyzed by comparing AUC values.
Drug AUC values can be used to determine other
pharmacokinetic parameters, such as clearance or
bioavailability, F. Similar techniques can be used to
calculate area under the first moment curve (AUMC)
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7) VOLUME OF DISTRIBUTION
Volume of distribution is the measure of the apparent space in the
body available to contain the drug.
Volume of distribution relates the amount of drug in the body to the
concentration of drug in blood or plasma .
Formula for volume of distribution is , total amount of drug in the
body divided by drug blood plasma concentration.
It is not a real but a theoretical volume.
if VD is greater, it shows that the drug is more diluted than it should
be (in the blood plasma), meaning more of it is distributed in tissue
(i.e. not in plasma).
It is defined as the distribution of a medication between plasma and
the rest of the body after oral or parenteral dosing.
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Volume of distribution may be increased
by renal failure (due to fluid retention)
and liver failure (due to altered body fluid).
Conversely it may be decreased in
dehydration.
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which can, in many respects, be envisioned more accurately as the actions of the body on an administered drug. It includes studies of the mechanisms of drug absorption, distribution, metabolism, and excretion; onset of action; duration of effect; biotransformation; and effects and routes of excretion of the metabolites of the drug. Pharmacokinetics determine how rapidly and for how long the drug will apear at the target organ.
. the degree to which a drug or other substance becomes available to the target tissue after administration. A measure of the amount of drug that is actually absorbed from a given dose. the degree to which a drug or other substance becomes available to the target tissue after administration. Clinical pharmacology The degree to which a drug is available to a target tissue after administration which, for oral drugs, reflects the rate and extent of GI tract absorption; BA is the in vivo presence of a substance in a form that allows it to be metabolized, serve as a substrate, bind a specific molecule, or participate in biochemical reactions. For dietary supplements, herbs and other nutrients in which the route of administration is nearly always oral, bioavailability generally designates simply the quantity or fraction of the ingested dose that is absorbed.[2]Bioavailability is defined slightly differently for drugs as opposed to dietary supplements primarily due to the method of administration and Food and Drug Administration regulations.Bioaccessibility is a concept related to bioavailability in the context of biodegradation and environmental pollution. A molecule (often a persistent organic pollutant) is said to be bioavailable when "[it] is available to cross an organism’s cellular membrane from the environment, if the organism has access to the chemical."
Absorption parameters : gastrointestinal track.
BioequivalenceIn determining bioequivalence, for example, between two products such as a commercially-available Brand product and a potential to-be-marketed Generic product, pharmacokinetic studies are conducted whereby each of the preparations are administered in a cross-over study to volunteer subjects, generally healthy individuals but occasionally in patients. Serum/plasma samples are obtained at regular intervals and assayed for parent drug (or occasionally metabolite) concentration. Occasionally, blood concentration levels are neither feasible or possible to compare the two products (e.g. inhaled corticosteroids), then pharmacodynamic endpoints rather than pharmacokinetic endpoints (see below) are used for comparison. For a pharmacokinetic comparison, the plasma concentration data are used to assess key pharmacokinetic parameters such as area under the curve (AUC), peak concentration (Cmax), time to peak concentration (Tmax), and absorption lag time (tlag). Testing should be conducted at several different doses, especially when the drug displays non-linear pharmacokinetics.In addition to data from bioequivalence studies, other data may need to be submitted to meet regulatory requirements for bioequivalence. Such evidence may include:1. analytical method validation2. In vitro-in vivo correlation studies(IVIVC)
Establish that a new formulation has therapeutic equivalence in the rate and extent of absorption to the reference drug product.Generic drug : a medication sold under its generic name ; usully legal only after the patent has expired or if no patent was issued for the substance . Generic drugs are usually less expensive than proprietry medication .
Anti-convulsants : a drug that relieves or prevent convulsions, A type of drug given to prevent seizures ,some patients with migrines can be treated effectively with an anti-convulsants. ( conulsions : an involuntry contraction or series of contraction of the voluntry muscles ).Anti-coagulants : substance that prevents coagulation of blood .Corticosteroids : Cardio-active drug :
the ratio between the dosage of a drug that causes a lethal effect and the dosage that causes atherapeutic effect.Medical Dictionarytherapeutic index n. The ratio between the toxic dose and the therapeutic dose of a drug, used as a measure of the relativesafety of the drug for a particular treatment.Quantitatively, it is the ratio given by the lethal or toxic dose divided by the therapeutic dose.In animal studies, the therapeutic index is the lethal dose of a drug for 50% of the population (LD50) divided by the minimum effective dose for 50% of the population (ED50).Lethality is not determined in human clinical trials; instead, the dose that produces a toxicity in 50% of the population (TD50) is used to calculate the therapeutic index.While the lethal dose is important to determine in animal studies, there are usually severe toxicities that occur at sublethal doses in humans, and these toxicities often limit the maximum dose of a drug. A higher therapeutic index is preferable to a lower one: a patient would have to take a much higher dose of such a drug to reach the lethal/toxic threshold than the dose taken to elicit the therapeutic effect.
Examples of biological half-lives[edit]WaterThe biological half-life of water in a human is about 7 to 14 days. It can be altered by behavior. Drinking large amounts of alcohol will reduce the biological half-life of water in the body.[3][4] This has been used to decontaminate humans who are internally contaminated with tritiated water (tritium). Drinking the same amount of water would have a similar effect, but many would find it difficult to drink a large volume of water. The basis of this decontamination method (used at Harwell) is to increase the rate at which the water in the body is replaced with new water.[edit]AlcoholThe removal of ethanol (drinking alcohol) through oxidation by alcohol dehydrogenase in the liver from the human body is limited. Hence the removal of a large concentration of alcohol from blood may follow zero-order kinetics. Also the rate-limiting steps for one substance may be in common with other substances. For instance, the blood alcohol concentration can be used to modify the biochemistry of methanol and ethylene glycol. In this way the oxidation of methanol to the toxic formaldehyde and formic acid in the (human body) can be prevented by giving an appropriate amount of ethanol to a person who has ingested methanol. Note that methanol is very toxic and causes blindness and death. A person who has ingested ethylene glycol can be treated in the same way. complex kineticsMetalsThe biological half-life of caesium in humans is between one and four months. This can be shortened by feeding the person prussian blue. The prussian blue in the digestive system acts as a solid ion exchanger which absorbs the caesium while releasing potassium ions.For some substances, it is important to think of the human or animal body as being made up of several parts, each with their own affinity for the substance, and each part with a different biological half-life (physiologically-based pharmacokinetic modelling). Attempts to remove a substance from the whole organism may have the effect of increasing the burden present in one part of the organism. For instance, if a person who is contaminated with lead is given EDTA in a chelation therapy, then while the rate at which lead is lost from the body will be increased, the lead within the body tends to relocate into the brain where it can do the most harm.[citation needed]Polonium in the body has a biological half-life of about 30 to 50 days.Caesium in the body has a biological half-life of about one to four months.Mercury (as methylmercury) in the body has a half-life of about 65 days.Lead in bone has a biological half-life of about ten years.Cadmium in bone has a biological half-life of about 30 years.Plutonium in bone has a biological half-life of about 100 years.Plutonium in the liver has a biological half-life of about 40 years.
MeSH definition : an abbreviations derived from MEDICAL SUBJECT HEADINGS , the list of medical terms used by NATIONAL LIBRARY OF MEDICINE ( NLM ) for its computerized system of storage and retrivel of published medical reports , this system is also used for indexing medical reference published in the monthly and annual volumes of index medicus …16000 terms .
AUC (area-under-the-curve): This is the overall amount of drug in the bloodstream after a dose. AUC studies are often used when researchers are looking for drug-drug or drug-food interactions. The way to get an AUC involves collecting many blood samples (usually every one or two hours) right after a person takes a dose up until the next dose is due. In each blood sample, the concentration of the drug is measured with a machine (discussed later). Then all the drug concentrations are put onto a graph based on the time after the dose that they were collected. A curve is made by connecting the points on the graph. The AUC for that drug is then calculated as the area under this drug concentration curve. An AUC study contains a lot of information about PK. It is probably the best way to understand how people handle a drug (PK).Cmax (maximum concentration): This is the highest concentration of drug in the blood that is measured after a dose. Cmaxusually happens within a few hours after the dose is taken. The time that Cmaxhappens is referred to as Tmax. For some antiretroviral drugs, a high Cmax is thought to increase the risk of side effects from the drug.Cmin or trough (pronounced "troff")(minimum concentration): This is the lowest concentration of the drug in the blood that is measured after a dose. It happens right before a patient takes the next usual dose. It is not known for certain, but many people in the HIV community believe that keeping the trough concentration (Cmin) above a certain level is especially important for anti-HIV activity.
Cmax , The maximum drug concentration. The maximum concentration of drug in the plasma is a function of both the rate and extent of absorption. Cmax will increase with an increase in the dose, as well as with an increase in the absorption rate. 3. Tmax , The time at which the Cmax occurs. The Tmax reflects the rate of drug absorption, and decreases as the absorption rate increases.
Area under first moment curve (AUMC) : plasma drug concentration x time after dosing versus time after drug administration.Mean resident times (MRT) : it is used for linear and non-linear systems.