All chemicals other than food that affect living processes are called drugs. This presentation will give a brief introduction of drugs and their action.

3. DEFINITION
HISTORY
DISEASE CLASSIFICATION
TYPES OF DRUGS
DRUGS NAMES

5. Definition
All chemicals other than food that affect
living processes

6. Since the beginning of human race
Alcohol
Tobacco
Coffee
Natural Drugs
Being used since 5000 years
Using Medicinal plants

7. A disease is a condition of impaired health resulting
from a disturbance in the structure or function of the
body.
Classified as:
 Infections
 Allergic Disease
 Metabolic Disorders
 Cancer
 Toxic Disease

8. Classification according to chemical structure or
pharmacological action.
Classified as:
 Chemotherapeutic agents
 Pharmacodynamic agents
 Miscellaneous agents

9. Route of Administration
Intravenous
Oral
Buccal
Sublingual
Rectal
Intramuscular
Transdermal
Subcutaneous
Inhalational
Topical

10. chemical name
brand or trade name
generic or common name

11. Blood flow
Protein binding
lipid solubility and the degree of ionisation

12. Actions of drugs are the biochemical
physiological mechanisms by which the
chemical produces a response in living
organisms.
Killing Foreign Organisms
Stimulation and Depression

13. Sites of Drug Action
Enzyme Inhibition
• Drugs act within the cell by modifying normal
biochemical reactions. Enzyme inhibition may
be reversible or non reversible; competitive or
non-competitive. Antimetabolites may be
used which mimic natural metabolites. Gene
functions may be suppressed.

14. 2. Drug-Receptor Interaction
Drugs act on the cell membrane by physical and/or
chemical interactions. This is usually through specific
drug receptor sites known to be located on the
membrane. A receptor is the specific chemical
constituents of the cell with which a drug interacts to
produce its pharmacological effects. Some receptor
sites have been identified with specific parts of
proteins and nucleic acids. In most cases, the
chemical nature of the receptor site remains
obscure.

15. 3. Non-specific Interactions
Drugs act exclusively by physical means outside
of cells. These sites include external surfaces
of skin and gastrointestinal tract. Drugs also
act outside of cell membranes by chemical
interactions. Neutralization of stomach acid by
antacids is a good example.

17. Pharmacokinetics is the study of
what the body does to a drug.
Pharmacodynamics is the study of
what a drug does to the body

18. Plasma Site of
Dosage Effects
Concen. Action
Pharmacokinetics Pharmacodynamics