SlideShare a Scribd company logo
1
PHARMACODYNAMICS
By
Dr. Faraza Javaid
2
AGONIST
When a drug binds to a receptor, there is
conformational change which initiates chain
of chemical events, leading to response, the
drug is said to be AGONIST.
3
Antagonist
The drug binds to receptor but does not activate
it, don't induce a conformational change, it has
no intrinsic activity.
Types of Agonists
FULL AGONIST: have a high efficacy and
are able to produce maximum response,
while occupying only small percentage of
receptors.
It has affinity and efficacy (activity) both.
4
For example, phenylephrine is a full agonist at
α1-adrenoceptors, because it produces the
same Emax as the endogenous ligand,
norepinephrine.
Upon binding to α1-adrenoceptors on vascular
smooth muscle, both norepinephrine and
phenylephrine stabilize the receptor in its
active state, thereby increasing Gq activation.
5
6
PARTIAL AGONIST: Have low efficacy and
are unable to elicit maximum response, even if
they occupy all available receptors, regardless
of concentration
e.g. Pindolol ( β-adrenoceptor blocker)
For example, aripiprazole, an atypical
antipsychotic, is a partial agonist at selected
dopamine receptors. Overactive dopaminergic
pathways tend to be inhibited by aripiprazole,
whereas underactive pathways are stimulated.
Inverse Agonist: is a drug that binds to a
same receptor as an agonist but induces a
pharmacological response opposite to that of
an agonist.
e.g. β-carbolines (at Benzodiazepine
receptor)
7
8
9
Types of Antagonist
Competitive antagonist
They bind to receptor reversibly.
The effect can be overcome by increasing
the concentration of agonist.
For example, the antihypertensive drug terazosin
competes with the endogenous ligand
norepinephrine at α1- adrenoceptors, thus
decreasing vascular smooth muscle tone and
reducing blood pressure.
10
Non-Competitive Antagonists
(Irreversible)
Bind covalently to the active site of receptors,
thereby reducing the number of receptors
available to the agonist.
The effect cannot be overcome by increasing
the concentration of drug.
E.g Phenoxybenzamine (alpha blocking drug)
Allosteric Antagonists
An allosteric antagonist binds to a site
(allosteric site) other than the agonist-binding
site and prevents receptor activation by the
agonist.
An example of an allosteric agonist is
picrotoxin, which binds to the inside of the
GABA controlled chloride channel.
When picrotoxin binds inside the channel, no
chloride can pass through the channel, even
when GABA fully occupies the receptor.
11
12
Spare Receptors
Many full agonists are capable of eliciting
maximal response at very low occupancies,
often less than 10%, such system is said to
be possess spare receptors.
This means response can be achieved with a
lower concentration of hormone or
neurotransmitter, than if fewer receptors
were present.
13
ANTAGONISM
When two drugs are give together, the
action of one drug opposes the action of
other drug.
Types of antagonism
Chemical antagonism
 Simple chemical interaction b/w two
drugs
 No receptor involved
e.g. Antacids and tetracycline given
together form unabsorbed solutes.
14
Physiological Antagonism
Drugs act on different receptors antagonizes
the physiological effect
Histamine H1-receptors relaxes vascular
smooth muscles producing hypotension
e.g. adrenaline α1-receptor VC, ↑ B.P
15
Synergism
Correlated action or cooperation on the part
of two or more drugs
ADDITIVE EFFECT (Summation):
When effect of two drugs having the similar
action are additive i-e 2+2=4
eg. β-adrenocptor blocker plus a thiazide
diuretics have an additive
antihypertensive effect.
16
POTENCIATION( to make more powerful)
when one drug increases the action of
other drug, i.e 2+2=5
e.g trimethoprim plus sulphonamide
or when one drug have no effect as own
but increases the effect of other drug
i.e 2+0 =5
eg. levodopa and carbidopa
17
POTENCY
It is a measure (in weight) of how
much drug is required to elicit a given
response.
Drug of high potency will generally
have a high affinity for the receptors
.
18
EFFICACY
Ability of the drug to produce maximum
response is called Efficacy
The capacity of the drug to activate the receptor
and response produced by a drug called
Intrinsic activity
19
THERAPEUTIC INDEX
This is related to safety of drug
It is the ratio between lethal dose and
effective dose.
Therapeutic index = Lethal dose
Effective dose
If therapeutic index is more than one the
drug is safe. If it is one or less it is not safe
e.g Digoxin
20
Dose:
It represents the amount of a drug to produce an effect
Therapeutic dose:
A dose which is required to produce a therapeutic effect
Toxic dose:
The dose which produces a toxic effect
Loading dose:
A large initial single or multiple doses are given for some
drugs to achieve a rapid steady state concentration
21
Maintenance dose:
The dose which is used to maintain the steady
– state concentration or to maintain the
therapeutic effect of a drug. It is given at a
fixed interval time
22
ED50 (Effective dose 50)
The dose or concentration which produces effect in
50% of the population in a group.
TD50 (Toxic dose 50)
The dose or concentration which produces toxic
effects in 50% of the population in a group.
LD50 (Lethal dose 50)
The dose or concentration which kills 50% of the
animals in a group
23
24
Pro-Drug
 It is a drug which is pharmacologically
inactive after administration, by the action
of enzymes, it is chemically altered
To active form in the body.
e.g Enalapril to Enalaprilat
Aspirin to Salicylates
Levodopa to Dopamine
Valciclovir to Acyclovier
THANK YOU
25

More Related Content

What's hot

Receptor - Pharmacology
Receptor - PharmacologyReceptor - Pharmacology
Receptor - Pharmacology
Harshit Jadav
 
Pharmacodynamics
PharmacodynamicsPharmacodynamics
Pharmacodynamics
abhishek2004
 
General pharmacology 2.1 pharmacodynamics
General pharmacology   2.1 pharmacodynamicsGeneral pharmacology   2.1 pharmacodynamics
General pharmacology 2.1 pharmacodynamics
MangeshBansod2
 
Principles of pharmacodynamics
Principles of pharmacodynamicsPrinciples of pharmacodynamics
Principles of pharmacodynamics
Jaineel Dharod
 
Concepts of agonist and antagonist receptors
Concepts of agonist and antagonist receptorsConcepts of agonist and antagonist receptors
Concepts of agonist and antagonist receptors
Central University of Gujarat, Gandhinagar
 
MECHANISM OF ACTION OF DRUGS
MECHANISM OF ACTION  OF DRUGSMECHANISM OF ACTION  OF DRUGS
MECHANISM OF ACTION OF DRUGS
Prathyusha Rani
 
Enzyme induction and inhibition
Enzyme induction and inhibitionEnzyme induction and inhibition
Enzyme induction and inhibition
Manjari Bodasu
 
Drug receptor interactions and types of receptor
Drug receptor interactions and types of receptorDrug receptor interactions and types of receptor
Drug receptor interactions and types of receptor
Dr. Siddhartha Dutta
 
Mechanism of drug action
Mechanism of drug actionMechanism of drug action
Mechanism of drug action
Pranesh Pawaskar
 
Drug receptors in pharmacology
Drug receptors in pharmacologyDrug receptors in pharmacology
Drug receptors in pharmacology
Bindu Pulugurtha
 
Spare receptors
Spare receptorsSpare receptors
Spare receptors
Dr Renju Ravi
 
Receptors
ReceptorsReceptors
Receptors
Dr Manju prasad
 
Opioid analgesics pharmacology
Opioid analgesics pharmacologyOpioid analgesics pharmacology
Opioid analgesics pharmacology
Koppala RVS Chaitanya
 
Receptors
ReceptorsReceptors
Corticosteroids Pharmacology - drdhriti
Corticosteroids Pharmacology - drdhritiCorticosteroids Pharmacology - drdhriti
Corticosteroids Pharmacology - drdhriti
http://neigrihms.gov.in/
 
Pharmacodynamics
PharmacodynamicsPharmacodynamics
Pharmacodynamics
BikashAdhikari26
 
Absorption and distribution of drugs
Absorption and distribution of drugsAbsorption and distribution of drugs
Absorption and distribution of drugs
Lok Raj Bhandari
 
Pharmacodynamics, mechanism of drug action
Pharmacodynamics, mechanism of drug actionPharmacodynamics, mechanism of drug action
Pharmacodynamics, mechanism of drug action
Asma Aslam
 
Mechanism of drug action
Mechanism of drug actionMechanism of drug action
Mechanism of drug action
Dr.Vijay Talla
 
Biotransformation of drugs
Biotransformation of drugsBiotransformation of drugs
Biotransformation of drugs
Akshaya Anil
 

What's hot (20)

Receptor - Pharmacology
Receptor - PharmacologyReceptor - Pharmacology
Receptor - Pharmacology
 
Pharmacodynamics
PharmacodynamicsPharmacodynamics
Pharmacodynamics
 
General pharmacology 2.1 pharmacodynamics
General pharmacology   2.1 pharmacodynamicsGeneral pharmacology   2.1 pharmacodynamics
General pharmacology 2.1 pharmacodynamics
 
Principles of pharmacodynamics
Principles of pharmacodynamicsPrinciples of pharmacodynamics
Principles of pharmacodynamics
 
Concepts of agonist and antagonist receptors
Concepts of agonist and antagonist receptorsConcepts of agonist and antagonist receptors
Concepts of agonist and antagonist receptors
 
MECHANISM OF ACTION OF DRUGS
MECHANISM OF ACTION  OF DRUGSMECHANISM OF ACTION  OF DRUGS
MECHANISM OF ACTION OF DRUGS
 
Enzyme induction and inhibition
Enzyme induction and inhibitionEnzyme induction and inhibition
Enzyme induction and inhibition
 
Drug receptor interactions and types of receptor
Drug receptor interactions and types of receptorDrug receptor interactions and types of receptor
Drug receptor interactions and types of receptor
 
Mechanism of drug action
Mechanism of drug actionMechanism of drug action
Mechanism of drug action
 
Drug receptors in pharmacology
Drug receptors in pharmacologyDrug receptors in pharmacology
Drug receptors in pharmacology
 
Spare receptors
Spare receptorsSpare receptors
Spare receptors
 
Receptors
ReceptorsReceptors
Receptors
 
Opioid analgesics pharmacology
Opioid analgesics pharmacologyOpioid analgesics pharmacology
Opioid analgesics pharmacology
 
Receptors
ReceptorsReceptors
Receptors
 
Corticosteroids Pharmacology - drdhriti
Corticosteroids Pharmacology - drdhritiCorticosteroids Pharmacology - drdhriti
Corticosteroids Pharmacology - drdhriti
 
Pharmacodynamics
PharmacodynamicsPharmacodynamics
Pharmacodynamics
 
Absorption and distribution of drugs
Absorption and distribution of drugsAbsorption and distribution of drugs
Absorption and distribution of drugs
 
Pharmacodynamics, mechanism of drug action
Pharmacodynamics, mechanism of drug actionPharmacodynamics, mechanism of drug action
Pharmacodynamics, mechanism of drug action
 
Mechanism of drug action
Mechanism of drug actionMechanism of drug action
Mechanism of drug action
 
Biotransformation of drugs
Biotransformation of drugsBiotransformation of drugs
Biotransformation of drugs
 

Similar to Pharmacodynamics.ppt

Pharmacodynamics (1)
Pharmacodynamics (1)Pharmacodynamics (1)
Pharmacodynamics (1)
Khalid Aftab, Ph.D.
 
Pharmacodynamics
Pharmacodynamics Pharmacodynamics
Pharmacodynamics
OPTOM FASLU MUHAMMED
 
Pharmacodynamics.ppt
Pharmacodynamics.pptPharmacodynamics.ppt
Pharmacodynamics.ppt
NuhuUsman1
 
Pharmacodynamics.pptx
Pharmacodynamics.pptxPharmacodynamics.pptx
Pharmacodynamics.pptx
ayman255825
 
2022_UMSU PHARMACODYNAMIC 1 2.pptx
2022_UMSU PHARMACODYNAMIC 1  2.pptx2022_UMSU PHARMACODYNAMIC 1  2.pptx
2022_UMSU PHARMACODYNAMIC 1 2.pptx
drRiyan1
 
Receptor - D. R. Mali
Receptor - D. R. MaliReceptor - D. R. Mali
Receptor - D. R. Mali
Dhanashri Mali
 
Receptor regulation in pharmacology.pptx
Receptor regulation in pharmacology.pptxReceptor regulation in pharmacology.pptx
Receptor regulation in pharmacology.pptx
SafuraIjaz2
 
Receptor regulation in pharmacology.pptx
Receptor regulation in pharmacology.pptxReceptor regulation in pharmacology.pptx
Receptor regulation in pharmacology.pptx
SafuraIjaz2
 
dynamics.ppt
dynamics.pptdynamics.ppt
dynamics.ppt
BdhadhHlkheDb
 
Dynamics
DynamicsDynamics
Dynamics
Manish Sharma
 
Pharmacodynamics
Pharmacodynamics Pharmacodynamics
Pharmacodynamics
Rahulvaish13
 
Parmacodynamics.pptx
Parmacodynamics.pptxParmacodynamics.pptx
Parmacodynamics.pptx
KeyaArere
 
Pharmacodynamics revised
Pharmacodynamics   revisedPharmacodynamics   revised
Pharmacodynamics revised
Omar Moatamed
 
Drug receptor-interactions
Drug receptor-interactionsDrug receptor-interactions
Drug receptor-interactions
Aizaz919930
 
Pharmacodynamics
PharmacodynamicsPharmacodynamics
Pharmacodynamics
A M O L D E O R E
 
Pharmacodynamics
PharmacodynamicsPharmacodynamics
Pharmacodynamics
Al Riyad Hasan
 
pharmacodynamic pharmacology
pharmacodynamic    pharmacologypharmacodynamic    pharmacology
pharmacodynamic pharmacology
Khyber Medical university
 
Pharmacodynamics (Receptor Pharmacology)
Pharmacodynamics (Receptor Pharmacology)Pharmacodynamics (Receptor Pharmacology)
Pharmacodynamics (Receptor Pharmacology)
Satyajit Ghosh
 
Overview of Pharmacodynamics
Overview of PharmacodynamicsOverview of Pharmacodynamics
Pharmacodynamics
PharmacodynamicsPharmacodynamics
Pharmacodynamics
Dr. Pramod B
 

Similar to Pharmacodynamics.ppt (20)

Pharmacodynamics (1)
Pharmacodynamics (1)Pharmacodynamics (1)
Pharmacodynamics (1)
 
Pharmacodynamics
Pharmacodynamics Pharmacodynamics
Pharmacodynamics
 
Pharmacodynamics.ppt
Pharmacodynamics.pptPharmacodynamics.ppt
Pharmacodynamics.ppt
 
Pharmacodynamics.pptx
Pharmacodynamics.pptxPharmacodynamics.pptx
Pharmacodynamics.pptx
 
2022_UMSU PHARMACODYNAMIC 1 2.pptx
2022_UMSU PHARMACODYNAMIC 1  2.pptx2022_UMSU PHARMACODYNAMIC 1  2.pptx
2022_UMSU PHARMACODYNAMIC 1 2.pptx
 
Receptor - D. R. Mali
Receptor - D. R. MaliReceptor - D. R. Mali
Receptor - D. R. Mali
 
Receptor regulation in pharmacology.pptx
Receptor regulation in pharmacology.pptxReceptor regulation in pharmacology.pptx
Receptor regulation in pharmacology.pptx
 
Receptor regulation in pharmacology.pptx
Receptor regulation in pharmacology.pptxReceptor regulation in pharmacology.pptx
Receptor regulation in pharmacology.pptx
 
dynamics.ppt
dynamics.pptdynamics.ppt
dynamics.ppt
 
Dynamics
DynamicsDynamics
Dynamics
 
Pharmacodynamics
Pharmacodynamics Pharmacodynamics
Pharmacodynamics
 
Parmacodynamics.pptx
Parmacodynamics.pptxParmacodynamics.pptx
Parmacodynamics.pptx
 
Pharmacodynamics revised
Pharmacodynamics   revisedPharmacodynamics   revised
Pharmacodynamics revised
 
Drug receptor-interactions
Drug receptor-interactionsDrug receptor-interactions
Drug receptor-interactions
 
Pharmacodynamics
PharmacodynamicsPharmacodynamics
Pharmacodynamics
 
Pharmacodynamics
PharmacodynamicsPharmacodynamics
Pharmacodynamics
 
pharmacodynamic pharmacology
pharmacodynamic    pharmacologypharmacodynamic    pharmacology
pharmacodynamic pharmacology
 
Pharmacodynamics (Receptor Pharmacology)
Pharmacodynamics (Receptor Pharmacology)Pharmacodynamics (Receptor Pharmacology)
Pharmacodynamics (Receptor Pharmacology)
 
Overview of Pharmacodynamics
Overview of PharmacodynamicsOverview of Pharmacodynamics
Overview of Pharmacodynamics
 
Pharmacodynamics
PharmacodynamicsPharmacodynamics
Pharmacodynamics
 

More from FarazaJaved

Endocrine Physiology.pptx
Endocrine Physiology.pptxEndocrine Physiology.pptx
Endocrine Physiology.pptx
FarazaJaved
 
AntidiarrhealAgents.pptx
AntidiarrhealAgents.pptxAntidiarrhealAgents.pptx
AntidiarrhealAgents.pptx
FarazaJaved
 
Treatment of Parkinsonism.pptx
Treatment of Parkinsonism.pptxTreatment of Parkinsonism.pptx
Treatment of Parkinsonism.pptx
FarazaJaved
 
Epilepsy and its treatment.pptx
Epilepsy and its treatment.pptxEpilepsy and its treatment.pptx
Epilepsy and its treatment.pptx
FarazaJaved
 
Drugs Excretion
Drugs ExcretionDrugs Excretion
Drugs Excretion
FarazaJaved
 
Design and Dose Optimization.pptx
Design and Dose Optimization.pptxDesign and Dose Optimization.pptx
Design and Dose Optimization.pptx
FarazaJaved
 
Routes of Drug Administration.ppt
Routes of Drug Administration.pptRoutes of Drug Administration.ppt
Routes of Drug Administration.ppt
FarazaJaved
 
Drug Metabolism.pptx
Drug Metabolism.pptxDrug Metabolism.pptx
Drug Metabolism.pptx
FarazaJaved
 
Drug Distribution.ppt
Drug Distribution.pptDrug Distribution.ppt
Drug Distribution.ppt
FarazaJaved
 
Absorption Pharmacokinetics.pptx
Absorption Pharmacokinetics.pptxAbsorption Pharmacokinetics.pptx
Absorption Pharmacokinetics.pptx
FarazaJaved
 
Drug Response.pptx
Drug Response.pptxDrug Response.pptx
Drug Response.pptx
FarazaJaved
 
Adverse Drug Reactions.ppt
Adverse Drug Reactions.pptAdverse Drug Reactions.ppt
Adverse Drug Reactions.ppt
FarazaJaved
 
Drugs Interactions.ppt
Drugs Interactions.pptDrugs Interactions.ppt
Drugs Interactions.ppt
FarazaJaved
 
Blood Coagulation and Clotting Mechanism.pptx
Blood Coagulation and Clotting Mechanism.pptxBlood Coagulation and Clotting Mechanism.pptx
Blood Coagulation and Clotting Mechanism.pptx
FarazaJaved
 
Estrogen and Antiestrogen.pptx
Estrogen and Antiestrogen.pptxEstrogen and Antiestrogen.pptx
Estrogen and Antiestrogen.pptx
FarazaJaved
 
Androgens and Anabolic Steroids and Anti-androgens.pptx
Androgens and Anabolic Steroids and Anti-androgens.pptxAndrogens and Anabolic Steroids and Anti-androgens.pptx
Androgens and Anabolic Steroids and Anti-androgens.pptx
FarazaJaved
 
CNS Physiology.pptx
CNS Physiology.pptxCNS Physiology.pptx
CNS Physiology.pptx
FarazaJaved
 
Local Anesthetics.pptx
Local Anesthetics.pptxLocal Anesthetics.pptx
Local Anesthetics.pptx
FarazaJaved
 
General Anestheics.pptx
General Anestheics.pptxGeneral Anestheics.pptx
General Anestheics.pptx
FarazaJaved
 
NSAIDs.pptx
NSAIDs.pptxNSAIDs.pptx
NSAIDs.pptx
FarazaJaved
 

More from FarazaJaved (20)

Endocrine Physiology.pptx
Endocrine Physiology.pptxEndocrine Physiology.pptx
Endocrine Physiology.pptx
 
AntidiarrhealAgents.pptx
AntidiarrhealAgents.pptxAntidiarrhealAgents.pptx
AntidiarrhealAgents.pptx
 
Treatment of Parkinsonism.pptx
Treatment of Parkinsonism.pptxTreatment of Parkinsonism.pptx
Treatment of Parkinsonism.pptx
 
Epilepsy and its treatment.pptx
Epilepsy and its treatment.pptxEpilepsy and its treatment.pptx
Epilepsy and its treatment.pptx
 
Drugs Excretion
Drugs ExcretionDrugs Excretion
Drugs Excretion
 
Design and Dose Optimization.pptx
Design and Dose Optimization.pptxDesign and Dose Optimization.pptx
Design and Dose Optimization.pptx
 
Routes of Drug Administration.ppt
Routes of Drug Administration.pptRoutes of Drug Administration.ppt
Routes of Drug Administration.ppt
 
Drug Metabolism.pptx
Drug Metabolism.pptxDrug Metabolism.pptx
Drug Metabolism.pptx
 
Drug Distribution.ppt
Drug Distribution.pptDrug Distribution.ppt
Drug Distribution.ppt
 
Absorption Pharmacokinetics.pptx
Absorption Pharmacokinetics.pptxAbsorption Pharmacokinetics.pptx
Absorption Pharmacokinetics.pptx
 
Drug Response.pptx
Drug Response.pptxDrug Response.pptx
Drug Response.pptx
 
Adverse Drug Reactions.ppt
Adverse Drug Reactions.pptAdverse Drug Reactions.ppt
Adverse Drug Reactions.ppt
 
Drugs Interactions.ppt
Drugs Interactions.pptDrugs Interactions.ppt
Drugs Interactions.ppt
 
Blood Coagulation and Clotting Mechanism.pptx
Blood Coagulation and Clotting Mechanism.pptxBlood Coagulation and Clotting Mechanism.pptx
Blood Coagulation and Clotting Mechanism.pptx
 
Estrogen and Antiestrogen.pptx
Estrogen and Antiestrogen.pptxEstrogen and Antiestrogen.pptx
Estrogen and Antiestrogen.pptx
 
Androgens and Anabolic Steroids and Anti-androgens.pptx
Androgens and Anabolic Steroids and Anti-androgens.pptxAndrogens and Anabolic Steroids and Anti-androgens.pptx
Androgens and Anabolic Steroids and Anti-androgens.pptx
 
CNS Physiology.pptx
CNS Physiology.pptxCNS Physiology.pptx
CNS Physiology.pptx
 
Local Anesthetics.pptx
Local Anesthetics.pptxLocal Anesthetics.pptx
Local Anesthetics.pptx
 
General Anestheics.pptx
General Anestheics.pptxGeneral Anestheics.pptx
General Anestheics.pptx
 
NSAIDs.pptx
NSAIDs.pptxNSAIDs.pptx
NSAIDs.pptx
 

Recently uploaded

CBL Seminar 2024_Preliminary Program.pdf
CBL Seminar 2024_Preliminary Program.pdfCBL Seminar 2024_Preliminary Program.pdf
CBL Seminar 2024_Preliminary Program.pdf
suvadeepdas911
 
Netter's Atlas of Human Anatomy 7.ed.pdf
Netter's Atlas of Human Anatomy 7.ed.pdfNetter's Atlas of Human Anatomy 7.ed.pdf
Netter's Atlas of Human Anatomy 7.ed.pdf
BrissaOrtiz3
 
Artificial Intelligence Symposium (THAIS)
Artificial Intelligence Symposium (THAIS)Artificial Intelligence Symposium (THAIS)
Artificial Intelligence Symposium (THAIS)
Josep Vidal-Alaball
 
Journal Article Review on Rasamanikya
Journal Article Review on RasamanikyaJournal Article Review on Rasamanikya
Journal Article Review on Rasamanikya
Dr. Jyothirmai Paindla
 
Tests for analysis of different pharmaceutical.pptx
Tests for analysis of different pharmaceutical.pptxTests for analysis of different pharmaceutical.pptx
Tests for analysis of different pharmaceutical.pptx
taiba qazi
 
Adhd Medication Shortage Uk - trinexpharmacy.com
Adhd Medication Shortage Uk - trinexpharmacy.comAdhd Medication Shortage Uk - trinexpharmacy.com
Adhd Medication Shortage Uk - trinexpharmacy.com
reignlana06
 
A Classical Text Review on Basavarajeeyam
A Classical Text Review on BasavarajeeyamA Classical Text Review on Basavarajeeyam
A Classical Text Review on Basavarajeeyam
Dr. Jyothirmai Paindla
 
Role of Mukta Pishti in the Management of Hyperthyroidism
Role of Mukta Pishti in the Management of HyperthyroidismRole of Mukta Pishti in the Management of Hyperthyroidism
Role of Mukta Pishti in the Management of Hyperthyroidism
Dr. Jyothirmai Paindla
 
Integrating Ayurveda into Parkinson’s Management: A Holistic Approach
Integrating Ayurveda into Parkinson’s Management: A Holistic ApproachIntegrating Ayurveda into Parkinson’s Management: A Holistic Approach
Integrating Ayurveda into Parkinson’s Management: A Holistic Approach
Ayurveda ForAll
 
REGULATION FOR COMBINATION PRODUCTS AND MEDICAL DEVICES.pptx
REGULATION FOR COMBINATION PRODUCTS AND MEDICAL DEVICES.pptxREGULATION FOR COMBINATION PRODUCTS AND MEDICAL DEVICES.pptx
REGULATION FOR COMBINATION PRODUCTS AND MEDICAL DEVICES.pptx
LaniyaNasrink
 
8 Surprising Reasons To Meditate 40 Minutes A Day That Can Change Your Life.pptx
8 Surprising Reasons To Meditate 40 Minutes A Day That Can Change Your Life.pptx8 Surprising Reasons To Meditate 40 Minutes A Day That Can Change Your Life.pptx
8 Surprising Reasons To Meditate 40 Minutes A Day That Can Change Your Life.pptx
Holistified Wellness
 
TEST BANK For Community Health Nursing A Canadian Perspective, 5th Edition by...
TEST BANK For Community Health Nursing A Canadian Perspective, 5th Edition by...TEST BANK For Community Health Nursing A Canadian Perspective, 5th Edition by...
TEST BANK For Community Health Nursing A Canadian Perspective, 5th Edition by...
Donc Test
 
Diabetic nephropathy diagnosis treatment
Diabetic nephropathy diagnosis treatmentDiabetic nephropathy diagnosis treatment
Diabetic nephropathy diagnosis treatment
arahmanzai5
 
Cardiac Assessment for B.sc Nursing Student.pdf
Cardiac Assessment for B.sc Nursing Student.pdfCardiac Assessment for B.sc Nursing Student.pdf
Cardiac Assessment for B.sc Nursing Student.pdf
shivalingatalekar1
 
Ear and its clinical correlations By Dr. Rabia Inam Gandapore.pptx
Ear and its clinical correlations By Dr. Rabia Inam Gandapore.pptxEar and its clinical correlations By Dr. Rabia Inam Gandapore.pptx
Ear and its clinical correlations By Dr. Rabia Inam Gandapore.pptx
Dr. Rabia Inam Gandapore
 
The Electrocardiogram - Physiologic Principles
The Electrocardiogram - Physiologic PrinciplesThe Electrocardiogram - Physiologic Principles
The Electrocardiogram - Physiologic Principles
MedicoseAcademics
 
CHEMOTHERAPY_RDP_CHAPTER 1_ANTI TB DRUGS.pdf
CHEMOTHERAPY_RDP_CHAPTER 1_ANTI TB DRUGS.pdfCHEMOTHERAPY_RDP_CHAPTER 1_ANTI TB DRUGS.pdf
CHEMOTHERAPY_RDP_CHAPTER 1_ANTI TB DRUGS.pdf
rishi2789
 
CHEMOTHERAPY_RDP_CHAPTER 6_Anti Malarial Drugs.pdf
CHEMOTHERAPY_RDP_CHAPTER 6_Anti Malarial Drugs.pdfCHEMOTHERAPY_RDP_CHAPTER 6_Anti Malarial Drugs.pdf
CHEMOTHERAPY_RDP_CHAPTER 6_Anti Malarial Drugs.pdf
rishi2789
 
Cell Therapy Expansion and Challenges in Autoimmune Disease
Cell Therapy Expansion and Challenges in Autoimmune DiseaseCell Therapy Expansion and Challenges in Autoimmune Disease
Cell Therapy Expansion and Challenges in Autoimmune Disease
Health Advances
 
Histololgy of Female Reproductive System.pptx
Histololgy of Female Reproductive System.pptxHistololgy of Female Reproductive System.pptx
Histololgy of Female Reproductive System.pptx
AyeshaZaid1
 

Recently uploaded (20)

CBL Seminar 2024_Preliminary Program.pdf
CBL Seminar 2024_Preliminary Program.pdfCBL Seminar 2024_Preliminary Program.pdf
CBL Seminar 2024_Preliminary Program.pdf
 
Netter's Atlas of Human Anatomy 7.ed.pdf
Netter's Atlas of Human Anatomy 7.ed.pdfNetter's Atlas of Human Anatomy 7.ed.pdf
Netter's Atlas of Human Anatomy 7.ed.pdf
 
Artificial Intelligence Symposium (THAIS)
Artificial Intelligence Symposium (THAIS)Artificial Intelligence Symposium (THAIS)
Artificial Intelligence Symposium (THAIS)
 
Journal Article Review on Rasamanikya
Journal Article Review on RasamanikyaJournal Article Review on Rasamanikya
Journal Article Review on Rasamanikya
 
Tests for analysis of different pharmaceutical.pptx
Tests for analysis of different pharmaceutical.pptxTests for analysis of different pharmaceutical.pptx
Tests for analysis of different pharmaceutical.pptx
 
Adhd Medication Shortage Uk - trinexpharmacy.com
Adhd Medication Shortage Uk - trinexpharmacy.comAdhd Medication Shortage Uk - trinexpharmacy.com
Adhd Medication Shortage Uk - trinexpharmacy.com
 
A Classical Text Review on Basavarajeeyam
A Classical Text Review on BasavarajeeyamA Classical Text Review on Basavarajeeyam
A Classical Text Review on Basavarajeeyam
 
Role of Mukta Pishti in the Management of Hyperthyroidism
Role of Mukta Pishti in the Management of HyperthyroidismRole of Mukta Pishti in the Management of Hyperthyroidism
Role of Mukta Pishti in the Management of Hyperthyroidism
 
Integrating Ayurveda into Parkinson’s Management: A Holistic Approach
Integrating Ayurveda into Parkinson’s Management: A Holistic ApproachIntegrating Ayurveda into Parkinson’s Management: A Holistic Approach
Integrating Ayurveda into Parkinson’s Management: A Holistic Approach
 
REGULATION FOR COMBINATION PRODUCTS AND MEDICAL DEVICES.pptx
REGULATION FOR COMBINATION PRODUCTS AND MEDICAL DEVICES.pptxREGULATION FOR COMBINATION PRODUCTS AND MEDICAL DEVICES.pptx
REGULATION FOR COMBINATION PRODUCTS AND MEDICAL DEVICES.pptx
 
8 Surprising Reasons To Meditate 40 Minutes A Day That Can Change Your Life.pptx
8 Surprising Reasons To Meditate 40 Minutes A Day That Can Change Your Life.pptx8 Surprising Reasons To Meditate 40 Minutes A Day That Can Change Your Life.pptx
8 Surprising Reasons To Meditate 40 Minutes A Day That Can Change Your Life.pptx
 
TEST BANK For Community Health Nursing A Canadian Perspective, 5th Edition by...
TEST BANK For Community Health Nursing A Canadian Perspective, 5th Edition by...TEST BANK For Community Health Nursing A Canadian Perspective, 5th Edition by...
TEST BANK For Community Health Nursing A Canadian Perspective, 5th Edition by...
 
Diabetic nephropathy diagnosis treatment
Diabetic nephropathy diagnosis treatmentDiabetic nephropathy diagnosis treatment
Diabetic nephropathy diagnosis treatment
 
Cardiac Assessment for B.sc Nursing Student.pdf
Cardiac Assessment for B.sc Nursing Student.pdfCardiac Assessment for B.sc Nursing Student.pdf
Cardiac Assessment for B.sc Nursing Student.pdf
 
Ear and its clinical correlations By Dr. Rabia Inam Gandapore.pptx
Ear and its clinical correlations By Dr. Rabia Inam Gandapore.pptxEar and its clinical correlations By Dr. Rabia Inam Gandapore.pptx
Ear and its clinical correlations By Dr. Rabia Inam Gandapore.pptx
 
The Electrocardiogram - Physiologic Principles
The Electrocardiogram - Physiologic PrinciplesThe Electrocardiogram - Physiologic Principles
The Electrocardiogram - Physiologic Principles
 
CHEMOTHERAPY_RDP_CHAPTER 1_ANTI TB DRUGS.pdf
CHEMOTHERAPY_RDP_CHAPTER 1_ANTI TB DRUGS.pdfCHEMOTHERAPY_RDP_CHAPTER 1_ANTI TB DRUGS.pdf
CHEMOTHERAPY_RDP_CHAPTER 1_ANTI TB DRUGS.pdf
 
CHEMOTHERAPY_RDP_CHAPTER 6_Anti Malarial Drugs.pdf
CHEMOTHERAPY_RDP_CHAPTER 6_Anti Malarial Drugs.pdfCHEMOTHERAPY_RDP_CHAPTER 6_Anti Malarial Drugs.pdf
CHEMOTHERAPY_RDP_CHAPTER 6_Anti Malarial Drugs.pdf
 
Cell Therapy Expansion and Challenges in Autoimmune Disease
Cell Therapy Expansion and Challenges in Autoimmune DiseaseCell Therapy Expansion and Challenges in Autoimmune Disease
Cell Therapy Expansion and Challenges in Autoimmune Disease
 
Histololgy of Female Reproductive System.pptx
Histololgy of Female Reproductive System.pptxHistololgy of Female Reproductive System.pptx
Histololgy of Female Reproductive System.pptx
 

Pharmacodynamics.ppt

  • 2. 2 AGONIST When a drug binds to a receptor, there is conformational change which initiates chain of chemical events, leading to response, the drug is said to be AGONIST.
  • 3. 3 Antagonist The drug binds to receptor but does not activate it, don't induce a conformational change, it has no intrinsic activity.
  • 4. Types of Agonists FULL AGONIST: have a high efficacy and are able to produce maximum response, while occupying only small percentage of receptors. It has affinity and efficacy (activity) both. 4
  • 5. For example, phenylephrine is a full agonist at α1-adrenoceptors, because it produces the same Emax as the endogenous ligand, norepinephrine. Upon binding to α1-adrenoceptors on vascular smooth muscle, both norepinephrine and phenylephrine stabilize the receptor in its active state, thereby increasing Gq activation. 5
  • 6. 6 PARTIAL AGONIST: Have low efficacy and are unable to elicit maximum response, even if they occupy all available receptors, regardless of concentration e.g. Pindolol ( β-adrenoceptor blocker) For example, aripiprazole, an atypical antipsychotic, is a partial agonist at selected dopamine receptors. Overactive dopaminergic pathways tend to be inhibited by aripiprazole, whereas underactive pathways are stimulated.
  • 7. Inverse Agonist: is a drug that binds to a same receptor as an agonist but induces a pharmacological response opposite to that of an agonist. e.g. β-carbolines (at Benzodiazepine receptor) 7
  • 8. 8
  • 9. 9 Types of Antagonist Competitive antagonist They bind to receptor reversibly. The effect can be overcome by increasing the concentration of agonist. For example, the antihypertensive drug terazosin competes with the endogenous ligand norepinephrine at α1- adrenoceptors, thus decreasing vascular smooth muscle tone and reducing blood pressure.
  • 10. 10 Non-Competitive Antagonists (Irreversible) Bind covalently to the active site of receptors, thereby reducing the number of receptors available to the agonist. The effect cannot be overcome by increasing the concentration of drug. E.g Phenoxybenzamine (alpha blocking drug)
  • 11. Allosteric Antagonists An allosteric antagonist binds to a site (allosteric site) other than the agonist-binding site and prevents receptor activation by the agonist. An example of an allosteric agonist is picrotoxin, which binds to the inside of the GABA controlled chloride channel. When picrotoxin binds inside the channel, no chloride can pass through the channel, even when GABA fully occupies the receptor. 11
  • 12. 12 Spare Receptors Many full agonists are capable of eliciting maximal response at very low occupancies, often less than 10%, such system is said to be possess spare receptors. This means response can be achieved with a lower concentration of hormone or neurotransmitter, than if fewer receptors were present.
  • 13. 13 ANTAGONISM When two drugs are give together, the action of one drug opposes the action of other drug. Types of antagonism Chemical antagonism  Simple chemical interaction b/w two drugs  No receptor involved e.g. Antacids and tetracycline given together form unabsorbed solutes.
  • 14. 14 Physiological Antagonism Drugs act on different receptors antagonizes the physiological effect Histamine H1-receptors relaxes vascular smooth muscles producing hypotension e.g. adrenaline α1-receptor VC, ↑ B.P
  • 15. 15 Synergism Correlated action or cooperation on the part of two or more drugs ADDITIVE EFFECT (Summation): When effect of two drugs having the similar action are additive i-e 2+2=4 eg. β-adrenocptor blocker plus a thiazide diuretics have an additive antihypertensive effect.
  • 16. 16 POTENCIATION( to make more powerful) when one drug increases the action of other drug, i.e 2+2=5 e.g trimethoprim plus sulphonamide or when one drug have no effect as own but increases the effect of other drug i.e 2+0 =5 eg. levodopa and carbidopa
  • 17. 17 POTENCY It is a measure (in weight) of how much drug is required to elicit a given response. Drug of high potency will generally have a high affinity for the receptors .
  • 18. 18 EFFICACY Ability of the drug to produce maximum response is called Efficacy The capacity of the drug to activate the receptor and response produced by a drug called Intrinsic activity
  • 19. 19 THERAPEUTIC INDEX This is related to safety of drug It is the ratio between lethal dose and effective dose. Therapeutic index = Lethal dose Effective dose If therapeutic index is more than one the drug is safe. If it is one or less it is not safe e.g Digoxin
  • 20. 20 Dose: It represents the amount of a drug to produce an effect Therapeutic dose: A dose which is required to produce a therapeutic effect Toxic dose: The dose which produces a toxic effect Loading dose: A large initial single or multiple doses are given for some drugs to achieve a rapid steady state concentration
  • 21. 21 Maintenance dose: The dose which is used to maintain the steady – state concentration or to maintain the therapeutic effect of a drug. It is given at a fixed interval time
  • 22. 22 ED50 (Effective dose 50) The dose or concentration which produces effect in 50% of the population in a group. TD50 (Toxic dose 50) The dose or concentration which produces toxic effects in 50% of the population in a group. LD50 (Lethal dose 50) The dose or concentration which kills 50% of the animals in a group
  • 23. 23
  • 24. 24 Pro-Drug  It is a drug which is pharmacologically inactive after administration, by the action of enzymes, it is chemically altered To active form in the body. e.g Enalapril to Enalaprilat Aspirin to Salicylates Levodopa to Dopamine Valciclovir to Acyclovier

Editor's Notes

  1. Ypes