Antibiotics are drugs that treat bacterial infections by either killing or inhibiting the growth of bacteria. There are several classes of antibiotics that work through different mechanisms such as inhibiting cell wall formation, interfering with DNA/protein formation, or preventing folic acid synthesis. While antibiotics are generally effective treatments, overuse and misuse has led to increased antibiotic resistance in bacteria. The document provides a detailed overview of the history, uses, mechanisms, types, and issues related to antibiotic use and resistance.

1. ALL YOU NEED TO KNOW ABOUT
ANTIBIOTICS
Prepared & Presented By:
Shuman Chandra Das
Sr. Product Executive, PMD
Asiatic Laboratories Ltd.
Contact: shumanpharma@gmail.com

2. WHAT IS ANTIBIOTIC
Antibiotics, also called antibacterials, are a type of antimicrobial
drug used in the treatment and prevention of bacterial infections.
They may either kill or inhibit the growth of bacteria.
The term antibiotic means "opposing life”.

3. USE OF ANTIBIOTIC
• Prophylactic therapy
– Infection is not present
– Preventing an infection
• Empiric therapy
– Infection is suspected & not documented
• Definitive therapy
– Infections is present
– Isolated a specific pathogen
– Specific therapy

4. HISTORY OF ANTIBIOTIC
Year Origin Description
1640 England
John Parkington recommended using mold for treatment in his book on
pharmacology
1870 England
Sir John Scott Burdon-Sanderson observed that culture fluid covered
with mould did not produce bacteria
1871 England
Joseph Lister experimented with the antibacterial action on human
tissue on what he called Penicillium glaucium
1875 England
John Tyndall explained antibacterial action of the Penicillium fungus to
the Royal Society
1877 France
Louis Pasteur postulated that bacteria could kill other bacteria (anthrax
bacilli)
1897 France
Ernest Duchesne healed infected guinea pigs from typhoid using mould
(Penicillium glaucium)
1928 England
Sir Alexander Fleming discovered enzyme lysozyme and the antibiotic
substance penicillin from the fungus Penicillium notatum
1932 Germany Gerhard Domagk discovered Sulfonamidochrysoidine (Prontosil )
During 1940's and 50's streptomycin, chloramphenicol, and tetracycline were discovered and Selman
Waksman used the term "antibiotics" to describe them (1942)

5. CLASSIFICATION OF ANTIBIOTIC
Penicillins:
a)Amoxicillin (E-mox)
b) Amoxicillin + ClavulanatePotassium
Tetracycline:
Doxycycline (E-doxy), Chlortetracycline
Macrolides:
Erythromycin, Azithromycin (Ezith),
Clarithromycin
Fluoroquinolones:
a) 1st Generation - Nalidixic, acid,
Cinoxacin.
b) 2nd Generation- Ciprofloxacin
(Cipron), Norfloxacin.
c) 3rd Generation- Levofloxacin (3-F),
Gemifloxacin.
d) 4th Generation- Trovafloxacin.
Cephalosporins:
a) 1st Generation – Cephradine (Efrad), Cephalexin (Edicef).
b) 2nd Generation- Cefuroxime.
c) 3rd Generation- Cefixime (3-C), Ceftriaxone (Edrucef).
d) 4th Generation- Meropenem (Edrupen).
Aminoglycoside:
Gentamycin (Egen), Streptomycin
Sulfonamide:
Sulfadiazine, Sulfamethoxazole

6. HOW ANTIBIOTIC WORKS
• Inhibit cell wall formation (Penicillin, Cephalosporin)
• Interfere with DNA formation (Quinolone, Nalidixic Acid, Ciproflxoacin)
• Block protein formation (Macrolides, Tetracyclines, Aminoglycosides)
• Prevent folic acid synthesis (Sulfonamides) • Prevents RNA (Rifampin)

7. SIDE EFFECTS
*Side effects ranging from mild to very severe depending on the type of
antibiotic used, the microbes targeted, and the individual patient
• Common side-effects include diarrhea due to overgrowth of pathogenic
bacteria, such as Clostridium difficile
• Adverse effects range from fever and nausea to major allergic reactions,
including photodermatitis and anaphylaxis
• Overgrowth of yeast species of the genus Candida in the vulvo-vaginal
area.
• Interaction with other drugs, such as the possibility of tendon damage
from the administration of a quinolone antibiotic with a systemic
corticosteroid.

8. BACTERIOSTATIC VS
BACTERICIDAL
• Biological or chemical
agent that Inhibits
bacterial growth.
• Eg: Azithromycin
• Biological or chemical
agent that Inhibits
bacterial growth kills
bacteria.
• Eg: Cefixime

9. ANTIBIOTIC VS ANTIBACTERIAL
• Antibiotic are class of
drugs which are used
against both
bacteria and fungi.
• This is a larger class
of drugs.
• antibiotics can be
antibacterial agents
• Antibacterials are
compounds that are
used only against
bacteria.
• This class of drugs
are major subclass
of antibiotic.
• all antibacterial
agents need not be
antibiotic.

10. BACTERIA
Gram Positive Bacteria
• Gram-positive bacteria retain
the color of the crystal violet
stain.
• cell wall composed of a thick
layer.
• Streptococci, Pneumococci
Gram Negative Bacteria
• Gram-negative bacteria lose
the crystal violet.
• composed of a thin layer of a
particular substance (called
peptidoglycan).
• E.coli, S. typhi
Bacteria are single-celled microorganisms that can exist either as
independent (free-living) organisms or as parasites (dependent on
another organism for life). Classification of Bacteria on the basis
of cell wall:

11. ANTIBIOTIC RESISTANCE
•Antibiotic Resistance is when bacteria are less treatable with one
or more antibiotics used to treat or prevent infections.
•Strains of bacteria can change (mutate) and, over time.
•A person does not finish the course of antibiotics they have been
prescribed.

12. ANTI FUNGAL DRUG
• An antifungal medication, also known as an antimycotic medication, is a
pharmaceutical fungicide or fungistatic used to treat and prevent mycoses such as
athlete's foot, ringworm, candidiasis (thrush), serious systemic infections such as
cryptococcal meningitis, and others.
• Such drugs are usually obtained by a doctor's prescription, but a few are available
OTC (over-the-counter).

13. ANTI VIRAL DRUG
• Antiviral drugs are a class of medication used specifically for
treating viral infections rather than bacterial ones.
• Most antivirals are used for specific viral infections, while a
broad-spectrum antiviral is effective against a wide range of
viruses.
• Unlike most antibiotics, antiviral drugs do not destroy their
target pathogen; instead they inhibit their development.

14. THANK YOU ALL