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INTRODUCTION TO
PHARMACOLOGY
Pharmacist Jeanette Jasper Tenga
(Mrs. J. Senkondo)
9th of November 2016
Common ground for the task ahead
1. Why do you want to become a medical
professional?
2. What would you like to be?
3. What do you think are going to be your
responsibilities?
(a) as a medical student and
(b) later as a medical professional.
4. What are your expectations during your time
learning Pharmacology?
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Assignment
 Read/watch the story of the following:1. Alice in Wonderland
2. The Life of an Eagle
 Understand, describe and practice
principles applied and the lessons learnt
from the above stories
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Alice in Wonderland
• A young girl when she 1st visited magical
Underland, Alice Kingsleigh (Mia Wasikowska) is
now a teenager with no memory of the place –
except her dreams. Her life takes a turn for the
unexpected when, at a garden party for her fiance
and herself, she spots a certain white rabbit and
tumbles down a hole after him. Reunited with her
friends the Mad Hatter (Johnny Depp), the
Cheshire Cat and others, Alice learns it is her
destiny to end the Red Queen’s (Helena Bonham
Carter) reign of terror
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Lessons to be learnt from Alice in
Wonderland
1. Do go down the rabbit hole (always follow the
white rabbit) sometimes you have to fall down a
rabbit hole to get to where you need to be
2. Know yourself
3. You are a different person today than you were
yesterday
4. Advice can come from the most unexpected
places
5. Believe in the impossible (dream of impossible
things)
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Lessons to be learnt from Alice in
Wonderland
6. Wandering doesn’t mean you are lost (there isn’t
just one way to get to a goal or destination)
7. My reality is different than yours
8. Existence is a lifetime of adventures ( in addition
to feelings, life is full of twists, turns, surprises,
disappointments, and so much more. You need to
accept that existence is a lifetime of adventures
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7 Principles of the Eagle
1. The Eagle flies at high altitude and it does
alone (If you ever want to do something great in
life, learn to be alone and when you are with
people, share your time with people of same
ambition and desires)
2. It has strong and unbelievable vision (Many
obstacle will appear to distract you in life. Stay
focused and never allow dissenting views and
voices to deter you from your vital goals in life)
3. Eats fresh prey ( Update yourself regularly with
fresh information from reliable sources)
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7 Principles of the Eagle…
4. Gets excited in the midst of storm
(Challenges should be your stepping stone
to your success and not to your
destruction. Learn to rest and soar during
the time of storm in your life)
5. Tests before trusting (test the
commitment of people before you trust
them with your time and resources)
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7 Principles of the Eagle
6. Prepares for training (the better you are
at managing your battles in life, the wiser
and more responsible you become.
Preparation is vital for future success)
7. Whet it feels weak, and about to die, he
retires to a place far away in the dark (
There is a need to learn how to retire to a
quiet place for periodic retreat and
strategic thinking with planning)
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Lessons to be learnt from The Life
of an Eagle
1. Decision
2. Following up on the decision (need
determination)
3. Killing the “Pity-party’ Syndrome (when
someone loves to get sympathetic platitudes on
any predicament they find themselves
4. Things get worse before it gets better
5. Change is a constant phenomenon
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Lessons to be learnt from The Life
of an Eagle
Conclusion:
The art of give and take is the only way we
can achieve anything tangible.
You have to be willing to do something in
order to get what you want
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Important Tips
• Do not walk in the dark during your
medical training
• Define where you want to go
• Think seriously on how to achieve your
goal and have the right attitude towards
learning, your lecturers, leaders and others
• In other words, create a reason to learn
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Important Tips...
• To anything you want to do make sure you Plan-DoCheck-Act (PDCA cycle)
• Use the formula 5W2H i.e.
 What
 Why
 Where
 Who
 When
 How
 How much
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Important Tips...
• To whatever you do, consider 3 things:
 interest
 time
 concentration
N.B: Fall in Love with Pharmacology
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Important Tips...
• To whatever you do, consider 3 things:…
 interest : (a feeling of wanting to learn more about
something or to be involved in something; a
quality that attracts your attention and makes you
want to learn more about something or to be
involved in something )
 time: (plan, schedule, set, arrange when
(something should happen or be done, organize)
 concentration: ( the action or power of focusing
all one’s attention, close attention)
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Department of Clinical
Pharmacology and Therapeutics
• Clinical Pharmaclogy :
 the science of drugs and their clinical use.
 It is underpinned by the basic science of
pharmacology, with added focus on the
application of pharmacological principles and
quantitative methods in the real world.
• Therapeutics:
 the branch of medicine concerned with the
treatment of disease and the action of remedial
agents.
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Department of Clinical
Pharmacology and Therapeutics
•
•
•
•
Head of Department: Prof. G. Rimoy
Coordinator: Mr. Walter Msangi
Technician: Mr. Walter Msangi
Lecturers: 1. Pharm. Jeanette Senkondo
: 2. Pharm. Amani Phillip
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Challenges in Clinical Pharmacology
for tomorrow’s doctors
• The number of licensed medicines is rapidly
increasing and doctors are increasingly
expected to prescribe medicines that are less
familiar to them
• Pace of new drug development is
accelerating rapidly as a result of advances
in molecular biology and mapping of the
human genome
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Challenges in Clinical Pharmacology
for tomorrow’s doctors...
• Patients are taking more medicines than before,
increasing the complexity of their treatment
regimen and the potential for drug interactions
• Newer drugs, capable of targeting previously
untreatable conditions, are often more powerful
but also more toxic
• The expansion of evidence-based medicine and
health technology assessment has enabled the
beneficial and adverse effects of drugs to be more
accurately quantified
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Challenges in Clinical Pharmacology
for tomorrow’s doctors...
• There are more sources of opinion and
disinformation available to patients and
doctors (increasing access to the internet)
• Marketing activites of the pharmaceutical
industry are a potential threat to costeffective prescribing decisions
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Clinical Pharmacology Training at
HKMU
• Semester 3
• Semester 4
All in MD2
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Clinical Pharmacology Training
at HKMU .....
• Semester 5 (MD3)
– Only protected time to concentrate on learning
the scientific basis for the principles of
therapeutics and gaining core knowledge and
understanding about drugs
• Clinical rotations
– Witness and learn about the use of drugs in
practice and gain skills in prescribing, drug
administration and attitudes towards the use of
drugs
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• The burden of factual knowledge is high in
Pharmacology
• You may feel overwhelmed by the number of drugs
described in pharmacology text books
• It is important to understand general
pharmacological principles, and to appreciate the
pharmacology of the main classes of drugs rather
than attempting to memorise details of individual
drugs
• Specific therapeutic drugs are best learned about near
a patient’s bedside
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• For each of the commonly used drugs in our
setting we expect the following from you:
– Know the name and class
– Have an understanding of the mechanism of
action
– Recognise the appropriate indication for use
– Know the appropriate route, frequency and
duration of administration
– Know the important contraindications, potential
interactions and adverse effects
– Know how to monitor the drug’s effects
– Be able to explain the salient features of all the
above to the patient
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General Learning Objectives
• To produce graduates who are competent
to prescribe safely, effectively and costeffectively.
• To provide the appropriate framework to be
able to assimilate information about new
drug developments that will occur
throughout a professional career
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Course Content
General Principles
of Pharmacology
Systems
Pharmacology
(Drugs affecting major
organ systems)
Chemical Mediators
Antimicrobial and
Cancer
Chemotherapy
(Drugs used for the treatment of infections,
cancer and immunological disorders)
Special
Topics
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Tutors’/Lecturers’/Instructors’
Responsibility
• Have a responsibility to the public, to employers
and the profession to make sure that graduates are
fit to practice;
and
• prescribing drugs is a key component of medical
practice
WE ARE NOT INTERESTED IN FAILING
ANY ONE!
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INTRODUCTION TO
PHARMACOLOGY
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Some Key Definitions
• Pharmacology:
 the study of the effects of chemical
substances/drugs on the function of living systems
OR
 the study of the manner in which the function of
living systems is affected by chemical agents
N.B: Knowledge of the normal & abnormal
functioning of the body is necessary
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Some Key Definitions....
• Drug:
a chemical substance of known structure,
other than a nutrient or an essential dietary
ingredient, which, when administered to a
living organism, produces a biological
effect
NB: like most definitions, this one has its limits. E.g. There
are a number of essential dietary constituents, such as iron
and various vitamins, that are used as medicines.
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• Drugs may be:
– Synthetic chemicals
– Chemicals from plants or animals
– Products of genetic engineering (biotechnology)
• To count as a drug, the substance must be
administered intentionaly to produce a certain
desired biological effect. i.e the substance must be
administered as such, rather than released by
physiological mechanisms.
• Many substances, e.g. Insulin or thyroxine, are
endogenous hormones but are also drugs when
administered intentionally
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Some key definitions
Drug…
• Many drugs are not used in medicines but are
nevertheless useful in research tools.
• The word drug is often associated with addictive,
narcotic or mind-altering substances- an
unfortunate negative connotation that tends to bias
uninformed opinion against any form of chemical
therapy.
• We will focus mainly on drugs used for
therapeutic purposes but also describe important
examples of drugs used as experimental tools.
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• A medicine:
chemical preparation which usually but not
necessarily contains one or more drugs,
administered with intention of producing a
therapeutic effect.
• Medicines usually contain other substances
(excipients, stabilisers, solvents etc) besides the
active drug, to make them more convenient to use
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Some key definitions….
Poison
• Poison: a substance that causes death or harm when
introduced into or absorbed by a living organism.
• Scientifically, a poison is any substance taken into the
body by ingestion, inhalation, injection, or absorption that
interferes with normal physiological functions.
• Virtually any substance can be poisonous if consumed in
sufficient quantity; therefore the term poison more often
implies an excessive degree of dosage rather than a
specific group of substances.
• Although poisons fall strictly within definition of drugs
they are not used in therapy
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Question!
• What is the difference between a Drug and
a Medicine????
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INTRODUCTION TO PHARMACOLOGY
Some Key Definitions…
Pharmacology can be defined as:
• The study of the manner in which the
functions of living systems is affected by
chemical agents
• Knowledge of the normal & abnormal
functioning of the body is necessary
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Pharmacology….
• Pharmacology comprises two broad
divisions, which are:
1. Pharmacodynamics-the biological and
therapeutic effects of drugs
2. Pharmacokinetics-the absorption,
distribution, metabolism and excretion of
drugs
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Pharmacology….
• The distinction can be put crudely thus
Pharmacodynamics is what drugs do to
the body
while
Pharmacokinetics is what the body does
to the drugs
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Pharmacology….
• It is self evident that knowledge of
pharmacodynamics is essential to the choice
of drug therapy.
• But the well-chosen drug may fail (or be
poisonous) because too little or too much is
present at the site of action for too short or
too long a time.
• Drug therapy can fail for pharmacokinetic as
well as for pharmacodynamic reasons.
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Pharmacodynamics
• Understanding the mechanisms of drug
action is not only an objective of the
pharmacologist who seeks to develop better
drugs , but also permits a more intelligent
use of medicines
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Pharmacodynamics…
• Consider the treatment of hypertension or asthma
for e.g.• Using combinations of drugs with the same mode
of action will not only provide additive therapeutic
effect but also additive adverse effects.
• Selection of combinations of drugs having different
modes of action will also provide additive
therapeutic efficacy and reduce the risk of additive
adverse effects
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Pharmacokinetics
• Studies in absorption/distribution/
metabolism and elimination of the drug in
man
• Will be studied in details later
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Development of Pharmacology as
a Scientific Discipline
Overview:
The objective of this introduction to pharmacology
session is:
 to explain how pharmacology came into being
and evolved as a scientific discipline and
 describe the present day structure of the subject
and its links to other biomedical sciences
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Development of Pharmacology as
a Scientific Discipline....
• Ancient prescientific therapeutics
– Herbal remedies were widely used
– No application of scientific principles to therapeutics
– Dogma used to explain therapeutic effects (magic, vital
forces)
• Pharmacology in the 19th century
– As a science Pharmacology was born in the mid-19th
century, out of increasing skills among doctors at
clinical observation and diagnosis but being ineffectual
when it came to treatment
– A need to improve outcome of therapeutic interventions
by doctors provided impetus for pharmacology
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Development of Pharmacology as
a Scientific Discipline....
• Until the late 19th century, knowledge of the
normal and abnormal functioning of the body was
too rudimentary to provide even a rough basis for
understanding drug effects;
• Disease and death were regarded as semi sacred
subjects, appropriately dealt with by authoritarian,
rather than scientific doctrines.
• Clinical practice often displayed an obedience to
authority and ignored what appear to be easily
ascertainable facts.
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– motivation for pharmacology (i.e. understanding what
drugs can and cannot do) came from clinical practice,
however, the science could be built only on the basis of
secure foundations in physiology, pathology and
chemistry which fortunately developed
– Rudolf Buchheim created the first pharmacology institute
(in his own house) in Estonia in 1847
– In its beginnings, before the advent of synthetic organic
chemistry, pharmacology concerned itself exclusively
with understanding of the effects of natural substances
(mainly plant extracts and a few toxic chemicals e. g.
Mercury and arsenic)
– Purification of active compounds from plants was
possible through early development in chemistry
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– 1805, Friedrich Serturner, a young German
apothecary, purified morphine from opium, and
other substances quickly followed, and, even
though their structures were unknown, these
– Compounds showed that chemicals, not magic or
vital forces, were responsible for the effects that
plant extracts produced on living organisms.
– 1858, Virchow proposed the cell theory
– the first use of structural formula to describe
chemical compounds was in 1868
– 1878, Bacteria as a cause of disease were
discovered by Pasteur
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• Early pharmacologists focused most of their
attention on such plant-derived drugs as
quinine, digitalis, atropine, ephedrine,
strychnine etc ( many of which are still used today
and maybe will have become old friends by the time you
graduate as a medical doctor).
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• Pharmacology in the 20th and 21st
centuries
– Beginning in the 20th century, the growth of
synthetic chemistry, and resurgence of natural
product chemistry revolutionalised the
pharmaceutical industry and the science of
pharmacology
– New synthetic drugs (barbiturates, local
anaesthetics) appeared
– Era of microbial chemotherapy began with the
discovery by Paul Ehrlich in 1909 of arsenical
compounds for treating syphilis
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– Gerhard Domagk, discovered sulfonamides, the
first antibacterial drugs in 1935
– Chain and Florey developed penicillin during the
Second World War, based on the earlier work of
Fleming
– By this time, pharmacology had really
established its identity and status among the
biomedical sciences
– Physiology was also making rapid progress
particulary in relation to chemical mediators
– Many hormones, neurotransmitters and
inflammatory mediators were discovered in this
period
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– The realisation that chemical communication
plays a central role in almost every regulatory
mechanism in living systems, established a large
area of common ground between physiology and
pharmacology (for interaction between chemical
substances and living systems were exactly the
interest of pharmacologists from begining)
– 1905, Langley first proposed the concept of
‘receptors’ for chemical mediators, and this was
quickly taken up by pharmacologists e.g. Clark,
Gaddum, Schild and others
– The Receptor concept and technologies developed
from it, have had a massive impact on drug
discovery and therapeutics
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– Biochemistry also emerged as a distinct science
in early 20th century
– Discovery of enzymes and delineation of
biochemical pathways provided yet another
framework for understanding drug effects
– The picture of pharmacology that emerges from
this brief glance at history is of a subject evolved
from ancient prescientific therapeutics, involved
in commerce from the 17th century onwards and
which gained respectability by donning the
trappings of science as soon as this became
possible in the mid-19th century.
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• The pharmaceutical industry has
become very big business and much
pharmacological research nowadays
takes place in a commercial
environment.
• The figure in the next slide shows the development of
pharmacology
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• The figure in the next slide shows Pharmacology
today with its various subdivisions.
• NOTE: interface disciplines (brown boxes) link
pharmacology to other mainstream biomedical disciplines
(green boxes)
• Read and understand the various subjects & terminologies
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Figure 1-2 Pharmacology today with its various subdivisions. Interface disciplines (brown boxes) link pharmacology to other mainstream biomedical disciplines (green boxes).
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Alternative therapeutic principles
•
•
•
•
•
Allopathy
Homoeopathy
Acupuncture
Herbalism
Aromatherapy
• H/W Read on the above
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• Modern medicine relies heavily on drugs as
the main tool of therapeutics
• Other therapeutic procedures e.g. surgery,
diet, excercise etc. ,are also important but
are less commonly used
• Therapeutic principles outside the domain
of science are currently gaining ground as
‘alternative’ or ‘complementary’ or
‘holistic’ medicine
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• The problem: they reject the medical model
which attributes disease to an underlying
derangement of normal function that can be
defined in biochemical or structural terms,
detected by objective means and influenced
beneficially by appropriate chemical or
physical interventions.
• They focus instead mainly on subjective
malaise, which may be disease associated or
not.
• Abandoning objectivity in defining and
measuring disease lead to;
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• Departure from scientific principles in
assessing therapeutic efficacy and risk
• Unfortunately, practices can gain public
acceptance without satisfying any of the
criteria of validity that would convince a
critical scientist, and that are required by law
to be satisfied before a new drug can be
introduced into therapy.
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Reference Books to be used
• Pharmacology by Rang & Dale
• Others:
-Katzung
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