INTRODUCTION TO PHARMACOLOGY

INTRODUCTION TO
PHARMACOLOGY

, Definition
PHARMACOLOGY:
Pharmacology is the science that deals with the study of
drugs and their interaction with the living systems.

DRUG:
Drug is a substance used in the diagnosis, prevention or treatment of disease.


PHARMACOKINECTICS:
Pharmacokinetics is the study of the absorption, distribution, metabolism and
elimination(excretion) of drugs, i.e. what the body does to a drug

, Definition
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 to 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.

, Definition
• Plasma half-life (t1/2) is the time taken for the plasma concentration of a drug
to be reduced to half its value.
• Minimum dose is the smallest dose required to produce a desired therapeutic
effect of the drug.
• Maximum dose is the largest dose of the drug that can be safely given to a
patient without producing harmful effect.
• Toxic dose is the dose of the drug which produce undesirable effects in majority
of the patients
• Lethal dose is the dose of the drug which can cause death. e.g. lethal dose of
phenobarbitone is 6-10gm.
• Bioavailability: Amount of drug to that reaches the systemic circulation