Pharmacology is the science of drugs, focusing on the interactions between chemical molecules and living systems, with key branches including pharmacokinetics, pharmacodynamics, toxicology, and chemotherapeutics. It encompasses the study of drug movement, effects, and applications for treatment and prevention of diseases. Terminology such as affinity, efficacy, agonists, and antagonists are essential for understanding drug actions and effects.

1. GENERAL
PHARMACOLOGY
PART 1

2. WHAT IS PHARMACOLOGY?
It is the science of drugs as it deals with the interaction of exogenously administered
chemical molecule (Drug) with living system.
Father of pharmacology: Oswald Schmiedeberg
Branches of pharmacology- Two main division of pharmacology are:
• 1. Pharmacokinetic [movement] : What the Body does to drug.
• 2. Pharmacodynamic [power] : What the Drug does to body.

3. • Other subdivision are-
 Chemotherapy- It includes the treatment via systemic infection/malignancy with specific drug that
have selective toxicity.
 Clinical pharmacology- The study of drug either new or old in human. The aim of this, is to generate
data for optimum use of drug and the practice of evidence based medicine.
 Pharmacotherapeutics- It is the application of pharmacological information tighter with knowledge of
the disease for its prevention, mitigation or cure. It also include selection of proper drug, dosage and
duration of treatment.
 Toxicology: It is the study of poisonous effect of drugs and other chemicals (household,
environmental pollutant, industrial, agricultural, homicidal) with emphasis on detection,
prevention and treatment of poisonings.
 Pharmacovigilence: It is the science and activities relating to detection, assessment,
understanding and prevention of adverse effect or any other possible drug related problem.

4. DRUG
• It is a single chemical entity present in a medicine that is used for diagnosis, prevention,
treatment/cure of a disease.
• According to the WHO : Drug is any substance or product that is used or is intended to be used
to modify or explore physiological system or pathological states for the benefits of recipient.

6. SOURCES OF DRUG
Plants
Animal
Minerals
Synthetic

7. DRUG NOMENCLATURE
• Existence of many names for each drug causes confusing situation.
• A DRUG HAS AT LEAST THREE TYPES OF NAMES:
Chemical name (IUPAC) or scientific name:
Based on molecular structure of the drug
Very long, too complex to use in common practice
International Nonproprietary/generic name:
Given by FDA/WHO while approved, the short hand version of chemical name
Recommended in RX
Proprietary/trademark/Brand name:
• Given by the pharmaceutical company
• Costly

8. ROUTE OF DRUG ADMINISTRATION
Classification
Local route
Arterial supply Deeper tissue Topical
Systemic
route
inhalation Parenteral
Subcutaneou
s
Intramuscular Intravenous Intradermal
Oral cutaneous Sublingual Rectal

9. TERMINOLOGIES
• Affinity: the ability of the drug to get bound to the receptor is known as
affinity.
• Efficacy:
• Intrinsic activity: The ability of the drug to produce a pharmacological action
after combining with the receptor.
• Agonist: A drug that is capable of producing pharmacological action after
binding to the receptor.
• Antagonist: Drugs that bind to receptor but are not capable of producing
pharmacological action. These produce receptor blockade.
• Competitive antagonist: they have affinity but no intrinsic activity.

10. PHARMACOKINTICS
• It is the quantitative study of drug movement in, through and out of the body. It attempts
to analyze chemical metabolism and to discover the fate of a chemical from the moment
that it is administered up to the point at which it is completely eliminated from the body.
Transportation Absorption Distribution Storage Metabolism Free drugReceptor Binding :
(Effect) Excretion Schematic Process of Pharmacokinetic:

11. PHARMACODYNAMICS
Pharmacodynamics is the study of drug effects. It attempts to elucidate the complete
action-effect sequence and dose-effect relationship.
PRINCIPLES OF DRUG ACTION: Drugs do not impart new function to any system , organ
or cell they only alter the pace of ongoing activity.
TYPES OF DRUG ACTION: Stimulation- Adrenaline Depression- Barbituates and general
anaesthetics Irritation- Methyl salicylate Replacement- Insulin for DM Cytotoxic action-
Anticancer drugs( Methotrxate)

12. THANKYOU
“Pharmacology is both a basic an applied science. It forms the
backbone of rational therapeutics.”