This document provides an introduction to the Department of Pharmacology at NEIGRIHMS. It discusses the history of pharmacology and some pioneering figures. Pharmacology is defined as the study of how chemicals affect living processes, including drugs, hormones, neurotransmitters and toxic agents. The roles of pharmacologists and medicinal chemists in drug discovery are described. Key terms like drug, pharmacokinetics, pharmacodynamics and therapeutic agents are defined. The relationships between pharmacokinetics and pharmacodynamics are outlined. Recommended pharmacology textbooks are also listed.

1. WELCOME TO
DEPARTMENT OF
PHARMACOLOGY,
NEIGRIHMS
Dr. D. K. Br ahma MD (Phar ma)
Asstt. Pr ofessor and in-char ge
Depar tment of Phar macology
NEIGRIHMS

3. PHARMACOLOGY
AN INTRODUCTION

4. History
Pioneers of Medicine and
Pharmacology:
• Hippocrates (450 B.C.)
• Francois Magendie (1783 - 1855)
• Claude Bernerd (1813 - 1878)
• Rudolf Buchheim (1820 to 1879)

5. What is Pharmacology ?
• From the Greek Pharmacon (drug), logos (a
discourse or treatise)
• Broadly defined as how chemical agents
affect living processes:
•
•
•
•
•
Hormones
Neurotransmitters
Growth factors
Drugs (pharmaceuticals)
Toxic agents in the environment

6. …contd.
• The medicinal/organic chemists may
create the candidate compound
(sometimes referred to as a new chemical
entity, (NCE), it is the pharmacologist who
is responsible for testing it for
pharmacological activity.
• Ultimately will lead to the discovery of
novel drugs for therapeutic intervention

7. What is a Drug?
• French: Drogue – a dry herb
• A single active chemical entity present in a
medicine that is used for diagnosis,
prevention and treatment of diseases
• WHO – in 1966 – “ Drug is any substance or
product which is used or intended to be
used to modify or explore physiological
systems or pathological states for the
benefit of the recipient.”
• Therapeutic or diagnostic or preventive
benefits Must …

8. …contd.
• Pharmacology studies the effects of drugs
and how they exert their effects:
• Paracetamol can reduce body temperature in
case of fever by inhibiting an enzyme known as
cyclooxygenase in CNS, which is responsible for
the synthesis of a number of inflammatory
mediators.
• Penicillin cures certain bacterial infections by
disrupting the synthesis of bacterial cell walls
by inhibiting a key enzyme.

9. Pharmacology is the unique
combination of several
Biomedical Sciences!
Ph
ys
iol
og
y
ch
o
Bi
try
is
em
Pharmacology
try
s
mi
he
C
M
ed
ici
n
e

10. Recommended Text
Books
Text Book
Author
Edition
The Pharmacological
Basis of Therapeutics
Goodman
Gillman
11th
Edition
Basic and Clinical
Pharmacology
Bertram G
Katzung
7th
Edition
Essentials of Medical
Pharmacology
K. D. Tripathi
Pharmacology and
Pharmacotherapeutics
Satoskar and
Bhandarkar
6th
edition,
2008
20th
Edition

11. Branches
of
Pharmacology
• TWO MAIN BRANCHES - Pharmacokinetics
& Pharmacodynamics
Pharmacokinetics:
(What Body does to Drugs?)
• Study the FATE of drugs once ingested and the
variability of drug response in varying patient
population
• Includes absorption, distribution, metabolism
and excretion of Drugs
Pharmacodynamics:
(What Drugs do to the Body?)
• Study the mechanisms by which Drugs act?
• Also study endogenous agents

12. Relationship – Dynamics
and Kinetics
Dosage Regimen
Absorption
Distribution
Metabolism
Excretion
Pharmacokinetics
Concentration in
Plasma
Pharmacodynamics
Concentration at the
site of action
Effect

13. Branches of
Pharmacology
Pharmacotherapeut
ics:
Use of Drugs for prevention
and cure of diseases –
clinical management of
diseases

14. Pharmacy and Clinical
Pharmacy
Definitions
• It is the art and science of compounding
and dispensing drugs or preparing
suitable dosage forms for administration
of drugs in man and animals. It also
includes identification, selection,
collection, purification, isolation,
standardization and quality control of
medicinal substances.
• Clinical pharmacy is a health science
discipline in which pharmacists provide
patient care that optimizes medication
therapy and promotes health, wellness,
and disease prevention

15. Some Other Definitions
• Pharmacoepidemiology: Study of effect of
Drugs on populations
• Pharmacoeconomics: Study of cost
effectiveness of drug treatment; the cost
of medications is of worldwide concern,
particularly among certain groups such as
elderly and AIDS patients

16. Definitions – contd.
• Chemotherapy: It is the branch of therapeutics
which is concerned with the effects of drugs upon
microorganisms and parasites, living or multiplying
in a living organism. It also includes the drugs
used in malignancy
• Pharmacognosy: is the science of identification of
drugs
• Toxicology: is the science of poisons which
includes detection and measurement of poisons as
well as treatment of poisoning. Poisons are the
substances causing harmful, dangerous or fatal
symptoms in man and animals.

17. Definitions – contd.
• Pharmacopoeia: It is
an official code
containing a selected
list of the established
drugs and medicinal
preparations with
descriptions of their
physical properties and
tests for their identity,
purity and potency.
Define the standards of
preparations.
Examples- BP, USP, IP
an EP

18. Definitions – contd.
• National Formulary: It is the book
published as product information on
drugs available to prescribers in
respective countries
Examples – National formulary – BNF
by BMA and PSGB
National Formulary of India is
published by Govt. of India.

19. Definitions – contd.
• Martindale The Extra Pharmacopoeia: It is
a voluminous database published
periodically by The Pharmaceutical Press
for Council of Royal Pharmaceutical
Society of Great Britain
• It contains concise reports on action
and uses of drugs available in most of
the world.

20. Essential Medicines
• WHO defines – “Essential Medicines are
those that satisfy the priority healthcare
needs of the population. Essential
medicines are intended to be available
within the context of functioning health
systems at all times and in adequate
amounts, in appropriate dosage forms,
with assured quality and adequate
information, and at a price the individual
and the community can afford.”
• 1977 – 1996 – 2003

21. Orphan Drugs
• These are the drugs or biological products
for diagnosis, prevention and treatment of
a rare disease or a more common disease
(endemic only in poor countries) for which
there is no reasonable expectation that the
cost of developing and marketing will be
recovered from the sale of these
medicines.
• Examples: Rifabutin, Succimer, Fomepizole
and liposomal amphotericin B etc.

22. Drug Nomenclature
1. Chemical Name – Chemical name
and code name
• Describe substances chemically
• For example - paraacetylaminophenol
1. Non-proprietary Name – USAN,
BAN, rINN, generic name.
2. Proprietary Name (Brand Name) Manufacturer

23. Drug Nomenclature –
contd.
1. Chemical Name –
•
•
Describe substances chemically
For example - paraacetylaminophenol …!
1. Non-proprietary Name – (USAN and
BAN)
•
PARACETAMOL
1. Proprietary Name –
•
Crocin, Calpol and ……..
(Similarly for aspirin …..)

24. Drug Nomenclature –
contd.
•
Chemical Name – “N-(4-Nitro-2phenoxyphenyl) methanesulfonamide”
[International union of Pure and Applied
chemistry (IUPAC)]
•
•
Non-proprietary Name – Nimesulide
Proprietary Name – Nise, Nimulid …. etc.

25. Drug Nomenclature –
New drug being
developed
1. Chemical Name or Code name
– RO 15-17288
2. Non-proprietary Name:
Flumazenil
(BAN, USAN and rINN) – approved
name/official name
3. Proprietary name: Anexate,
Lanexat, Mazicon, Romazicon

26. Sources of Drugs
• Plant sources – Morphine, digoxin, quinine,
atropine, reserpine , vinca alkaloids and paclitaxel.
• Animal sources – Insulin, Thyroid extract, heparin,
gonadotrophins and antitoxic sera.
• Minerals – Liquid paraffin, magnesium sulfate,
magnesium trisilicate, ferrous sulfate and kaolin.
• Micro – organisms – Bacteria and fungi – Penicillin,
Streptomycin
• Synthetic – Analgesics, hypnotics, anticancer drugs
and antimicrobials
• Genetic Engineering – Human insulin, growth
hormone genes
• Hybridoma technique – monoclonal antibodies
origin

27. Plant Sources
• Alkaloids: Water soluble salts of water insoluble
nitrogenous compounds e.g. Atropine
• Glycosides: Ether-like combination of sugar with
other organic acids. Acid hydrolysis separates
sugar from non-sugar moiety
• Oils: Glycerides of oleic, palmitic or stearic acids
• Fixed oils: Peanut oil, coconut oil and castor oil
• Volatile oils: Peppermint oil, ginger, eucalyptus
oil etc.
• Resins: Oxidized or polymerized volatile oils
• Oleoresins: Mixture of volatile oils and resins
• Gums: Secretory products of plants

28. Opium Alkaloid
Extraction

29. Routes of Drug Administration

30. Choices of Routes of
Drugs
• Drugs may be acidic, basic, or neutral and come in
a variety of chemical forms such as small organic
molecules, large polymers such as proteins,
carbohydrates and other compounds with complex
chemistries
• Physical and chemical properties of drug –
solid/gas/liquid or solubility, pH etc.
• Site of desired action – localized or generalized
• Effect of digestive juices and first pass metabolism of
drug
• Accuracy of dosage required
• Condition of the patient – unconscious, vomiting etc.

31. Local Routes
1.
2.
3.
Topical – External application of the drug
to the surface for localized action, e.g.
lotion, ointment, cream, powder, paints,
and spray etc.
Deeper tissues – Certain deep areas can
be approached by syringe and needle,
e.g. intra-articular, intra-medullarly, intralesional injection, intrathecal and
infiltration
Arterial supply – Closed intra arterial
injection, e.g. angiography and
anticancer drugs.

32. Routes - Enemata
• Application of medicaments into rectum
• Two types:
• Evacuant enema: Mainly liquid form for
local action e.g., soap water enema
• Quantity of fluid 600 ml
• Retention enema: Mainly solid form
meant for systemic action e.g.,
prednisolone enema

33. Systemic Routes –
1.Oral (enteral)
ADVANTAGES:
DISADVANTAGES:
•
•
•
• Self medication
possible – no
assistance required
•
•
Vast area of absorption
Simplicity of procedure –
no extra cost
Slow in action and hence
safe with some risky
drugs
Both solid and liquid
dosage forms can be
given
•
•
•
•
•
•
Onset of action is tardy
Irritant and unpalatable
drugs cannot be
administered
Absorption is irregular with
some drugs e.g.
aminoglycosdes
May induce nausea and
vomiting
Not useful in presence of
vomiting and diarrhoea
Can be destroyed by gastric
juice – penicillin G, insulin
Cannot be used in
unconscious and
uncooperative patient.

34. Oral Route – contd.
• Enteric coated: with acetate-pthalate,
glutean and anionic polymers of
methacrylic acid and its esters.
• To prevent gastric irritation and alteration of
drug in stomach.
• To achieve desired concentration of drug in
small intestine
• To retard the absorption of drug
• Controlled release (CR):
Timsules/Spansules
• To provide uniform medication for prolonged
period

35. 2. Sublingual
• Kept under the tongue or crushed and spread over
the buccal mucosa
• Advantages:
•
•
•
•
rapid absorption – action in 1 minute
liver is bypassed – directly in systemic circulation
can spit out the drug
Unconscious patients
• Disadvantages:
• Only lipid soluble drugs
• Uncooperative patients
• Irritation of mucosa
Drugs: GTN (Glyceryl trinitrate), Buprenorphine
(Nifedepine)

36. 3. Rectal
• Irritant and unpleasant drugs as
suppositories or retention enema
• Can be used in presence of vomiting
and unconsciousness
• Absorbed by external hemorrhoid
veins – bypasses liver
Drugs – Diazepam, Indomethacin and
Aminophylline etc.

37. 4. Inhalation
• Very rapid absorption due to vast
surface area of lungs
• General anesthetics – gases and liquids
• Pressurized metered dose aerosols - MDI
• Dry powder inhalation - Rotahalers

38. 5. Nasal
• Absorbed by mucous membrane
of the nose
• Hepatic first pass metabolism
and gastric juices are bypassed
(GnRH agonists like Leuprolide,
dDAVP and calcitonin)

39. 6. Parenteral (Par –
beyond, enteral – intestine)
Advantages:
• Unconscious and
uncooperative patient
• In presence of vomiting
and diarrhea
• Irritant drugs
• By pass alimentary
juice and 1st pass
metabolism
• Rapid action and
accuracy of dose
Disadvantages:
• Costly and painful
• Self medication is
difficult
• Less safe and chance
of infection
• Injury to nerves and
arteries
• Risky

40. Parenteral Route –
contd.
•
•
•
•
•
•
Intradermal
Subcutaneous
Intramuscular
Intravenous
Intrathecal
Intraperitoneal

41. Intradermal and
Subcutaneous
Intradermal:
BCG and sensitivity Tests
Subcutaneous:
• Non-irritant substances
• Small amount as less vascular
• Self injection is possible
• Avoid in shock
• Repository depot preparations
– aqueous suspensions
Best example – Insulin
Hypodermoclysis

42. Intramuscular
• Soluble substances, mild
irritants, suspensions and
colloids
• Sites of Injection – buttock,
deltoid muscle
• No IM injection to child before
walking

43. Intravenous route
Advantages
Disadvantages
• Quick action – ideal for
emergency
• Desired concentration
can be obtained
• No hepatic first pass
metabolism
• Can be used in
unconscious and
uncooperative patients
•
•
•
•
•
•
Costly – special apparatus
required
Thrombophlebitis and local
irritation
Self medication not
possible
Action cannot be halted
Extravasation may cause
severe irritation
Aseptic and antiseptic
measures to be maintained

44. Transcutaneous Routes
• Innunction: Nitroglycerin in angina pectoris
• Iontophoresis: Galvanic current is for penetration
of drugs to deeper tissues – anode and cathode
iontophoresis e.g., salicylates
• Jet injection: Painless injection – high velocity jet
produced through a microfine orifice
• Transdermal therapeutic system (Novel drug
delivery): Examples – GTN, Nicotine and Estrdiol
• Scopolamine patch
• Implants: Biodegradable and non-biodegradable.
Example - Norplants

45. Transcutaneous images
Inuncti
on
Transdermal
Dermojet

46. Special Drug Delivery
System
• Ocusert: Pilocarpine, progestsert
• Prodrug: Examples
• levodopa to dopamine
• Chloramphenicol palmitate
• Targeted delivery: Monoclonal
antibodies
• Liposomes: daunorubicin,
doxorubicin nd amphotericin B etc.

47. Remember
• Drug Nomenclature
• Sources of Drugs with examples of each
• Active pharmacological components of
plants
• Routes of administration of Drugs with
examples
• Advantages and Disadvantages of different
routes
• Special drug delivery systems

48. Thank You
Montoux test