introduction to pharmacology, scope of pharmacology, routes of administration of drugs.

1. INTRODUCTION TO PHARMACOLOGY
Miss. Shingan A.V.

2. INDEX
 INTRODUCTION TO PHARMACOLOGY
 SCOPE OF PHARMACOLOGY
 ROUTES OF DRUG ADMINISTRATION

3. DEFINITION:
Pharmacology is the science that deals with the study of drugs and their
interaction with the living systems.
The word Pharmacology is derived from Greek pharmacon means drug and
logos means study.
DRUG:
Drug is a substance used in the diagnosis ,prevention or treatment of
disease.
PHARMACOKINECTICS:
Pharmacokinectics is the study of the absorption distribution ,metabolism
and excretion of drugs i.e what the body does the drug (in greek kinesis =
movement).
INTRODUCTION TO PHARMACOLOGY

4. PHARMACODYNAMICS :
Pharmacodynamics is the study of the effect of the drugs on the body and
their mechanism of action ,i.e what the drug does the body.
THERAPEUTICS:
Therapeutics deals with the use of drugs in the prevention and treatment of
disease.
TOXICOLOGY :
Toxicology deals with the adverse effect of the drug and also the study of
poisons,i.e detection ,prevention and treatment of poisoning.(Toxicon
=poison in Greek).
INTRODUCTION TO PHARMACOLOGY

5. INTRODUCTION TO PHARMACOLOGY
CHEMOTHERAPY :
Chemotherapy is the use of chemicals for the treatment of infections. the
term now also includes the use of chemical to treat malignancies.
PHARMACY :
Pharmacy is the science of identification , compounding and dispensing
of drugs .It also includes collection , isolation, purification , synthesis
and Standardization of medical substances.

6. INTRODUCTION TO PHARMACOLOGY
DESIRED ACTION:
the expected response of a medication
SIDE EFFECTS:
known and frequently experienced, expected reaction to drug.
ADVERSE REACTION:
unexpected, unpredictable reactions that are not related too usual effects of
a normal dose of the drug.
DRUG INTERACTIONS:
Takes place when one drug alters the action of another drug.

7. TYPES OF PHARMACOLOGY
1. EXPERIMENTAL PHARMACOLOGY:
Done in the laboratory on experimental animals such as
rodents and non rodents.
2. CLINICAL PHARMACOLOGY:
On human subjects normal or deceased
INTRODUCTION TO PHARMACOLOGY

8. CLASSIFICATION OF DRUGS
1.Chemical nature
2.Source
3.Target organ/site of action
4.Mode of action
5.Therapeutic uses
6.Physiological system
7.Physical effects
INTRODUCTION TO PHARMACOLOGY

9. SCOPE OF PHARMACOLOGY
ACADEMICS:
UNDERGRADUATE EDUCATION
 Introduction to drugs mechanisms of actions
 Prescription writing
 Pharmaceutical preparations
 Identification of adverse drug reactions
POSTGRADUATE EDUCATION:
 Basic research
 Experimental pharmacology pharmacokinetics
 Pharmacovigilance
 Clinical pharmacology
 Therapeutic drug monitoring

10. INDUSTRIES:
 Medical advisor
 Medical transcription
 Medico marketing
 Product management
 Contract research organization
 Training
 Research: new drug development
SCOPE OF PHARMACOLOGY

11. SPECIAL DOMAINS:
 Pharmacoeconomics
 Pharmacoepidemiology
 Chronopharmacology
 Pharmacovigilance
SCOPE OF PHARMACOLOGY

12. Research:
 Drug development.
 Drug discovery.
 Clinical trial.
SCOPE OF PHARMACOLOGY

13. FUTURE SCOPE
 Proteomics
 Pharmacogenomics & pharmacogenetics
 Bioinformatics
 Nanomedicine
SCOPE OF PHARMACOLOGY

14. ROUTES OF DRUG ADMINISTRATION

15. ROUTES OF DRUG ADMINISTRATION
FACTORS GOVERNING CHOICE
OF ROUTE
 Physical & chemical properties of drug-
solid/liquid/gas; solubility, stability, PH, irritancy
 Site of desired action- localized and approachable or
generalized and non approachable
 Rate & extent of absorption from various routes
Effect of digestive juices & first pass effect
 Rapidity of the desired response- emergency/routine
Accuracy of dosage
 Condition of the patient- unconscious, vomiting

16. ROUTES OF DRUG ADMINISTRATION
ORAL ROUTE
The most common route of drug administration.
Drug is given through oral cavity.
ADVANTAGES
1. Safe
2. Convenient- self- administered, pain free, noninvasive and easy to take Economical-
compared to other parentral routes
3. Usually good absorption- takes place along the
4. whole length of the GI tract
5. No need for sterilization
DISADVANTAGES
1. Slow absorption slow action - can not used in emergency
2. Irritable and unpalatable drugs- nausea and Vomiting
3. Cannot be used Unco-operative, vomiting and unconscious patien
4. Some drugs destroyed
5. Sometimes inefficient drug absorbed, some drugs are not absorbed like
streptomycin
6. First-pass effect- Due to Biotransformation
7. Food–Drug interactions and Drug-Drug interactions

17. ROUTES OF DRUG ADMINISTRATION
SUBLINGUAL/BUCCAL ROUTE:
Tab or pellet containing the drug is placed under tongue or crushed in
mouth and spread over the buccal mucosa. Ex- GTN, buprenorphine,
desaminooxytocin.
ADVANTAGES
Drug absorption is quick
Quick termination
First-pass avoided
Can be self administered Economical
DISADVANTAGES
Unpalatable & bitter drugs
Irritation of oral mucosa
Large quantities not given
Few drugs are absorbed

18. ROUTES OF DRUG ADMINISTRATION
RECTAL ROUTE
Drugs that are administered rectally as a suppository. - In this form, a drug is
mixed with a waxy substance that dissolves or liquefies after it is inserted into
the rectum. - ex- Diazepam, indomethacin, paraldehyde, ergotamine.
ADVANTAGES
Used in children
Little or no first pass effect (ext haemorrhoidal vein)
Used in vomiting or unconscious
Higher concentrations rapidly achieved
DISADVANTAGES
Inconvenient
Absorption is slow and erratic
Irritation or inflammation of rectal mucosa can occur

19. ROUTES OF DRUG ADMINISTRATION
PARENTERALROUTES
Direct delivery of drug in to systemic circulation without intestinal
mucosa
 Intradermal (I.D.) (into skin)
 Subcutaneous (S.C.) (into subcutaneous tissue)
 Intramuscular (I.M.) (into skeletal muscle)
 Intravenous (I.V.) (into veins)
 Intra-arterial (I.A.) (into arteries)
 Intrathecal (I.T.) (cerebrospinal fluids )
 Intraperitoneal (I.P.) (peritoneal cavity)
 Intra-articular (Synovial fluids)

20. ROUTES OF DRUG ADMINISTRATION
ADVANTAGES
 high bioavailability
Rapid action (emergency)
 No first pass metabolism
Suitable for
 Vomiting &unconsciousness
 Irritant & Bad taste drugs.
 No gastric irritation
 No food-drug interaction
DISADVANTAGES
 Infection
 Sterilization
 Invasive
 assistance require
 Pain
 Needs skill
 Anaphylaxis
 Expensive.
PARENTERALROUTES
Dosage form:
Vial or ampoule

21. ROUTES OF DRUG ADMINISTRATION
 Produce local effect to
Skin (percutaneous) e.g. allergy testing, topical
local anesthesia
 Mucous membrane of respiratory tract
(Inhalation) e.g. asthma
 Eye drops e.g. conjunctivitis
 Ear drops e.g. otitis externa
 Intranasal, e.g. decongestant nasal spray
TOPICAL APPLICATION

22. ROUTES OF DRUG ADMINISTRATION
No single method of drug
administration is ideal for all drugs in all
circumstances