Antimicrobial agents can be categorized into antibiotics, antimicrobial agents, and chemotherapeutic agents. Antibiotics are secondary metabolites produced naturally by microorganisms like bacteria and fungi that inhibit or kill other microbes. Antimicrobial agents include both synthetic and natural drugs that suppress microbial growth. Chemotherapeutic agents are drugs designed to inhibit or kill infecting organisms with minimal effects on the recipient. These agents include antibiotics and anti-microbial drugs used to treat bacterial, viral, fungal and parasitic infections.

1. Antimicrobial Chemotherapy
1. ANTIBIOTICS
2. ANTIMICROBIAL AGENTS
3. CHEMOTHERAPEUTIC AGENTS
1. ANTIBIOTICS:
Antibiotics are the secondary metabolities which are secreated by Bacterial of Fungi which are
inhibit or to killed the growth of other bacterial or fungi.
Natural substances produced by various species of microorganisms. Like,
 Bacteria
 Bungi
 Actinomycetes
suppress growth / kill other microorganisms .
2. ANTIMICROBIAL AGENTS
Synthetic analogues.
Includes synthetic as well as naturally obtained drugs that attenuate microorganisms.
These are secondary metabolities of bacterial or fungi which ae produced through sunthetic
procedure in the industries.
These are also used to inhibit or to killed the growth of other microorganisms.
3. CHEMOTHERAPEUTIC AGENTS
Drugs in this class differ from all others in that they are designed to inhibit/kill the infecting
organism and have no/minimal effect on the recipient.
The drugs also known as agents that are known to be used in chemotherapy for cancer
(wikipedia)-most specifically any how they also includes drugs used as antibiotics.

2. Microorganisms of medical improtance fall into four categories
 Bacteria
 Viruses
 Fungi
 Parasites
Antimicrobial chemotherapy
Use of drugs to combat infectious agents
 Anti-bacterial
 Anti-viral
 Anti-fungal
 Anti-parasitic agents
 Differential ( selective ) toxicity : Based on the concept that the drug is more toxic to the
infecting organism than to the host.
 Majority of antibiotics are based on naturally occuring compounds.
 OR may be semi-synthetic or sunthetic.
What is the ideal antibiotic
 Have the appropriate of activity for the clinical setting.
 have no toxicity to the host, be well tolerated.
 Not induce hypersensitivies in the host.
 Have rapod and extensive tissue distribution.
 Have a relatively long half-life.
 Be free of interaction with other drugs.
 Be convenient for administration.
 Be relatively inexpensive.

3. Principles/Definitions: