Introduction-to-Cephalosporins-Chemotherapy in short

1. Introduction to
Cephalosporins
Chemotherapy
Cephalosporins are a class of antibiotics used to treat a wide range of
bacterial infections. They are derived from a fungus called Acremonium.
These antibiotics work by interfering with the production of peptidoglycan
in the bacterial cell wall, ultimately leading to cell death.
S by
Prof. Sudha Unmesh Puri
Assistant Professor
Department of Pharmacology
JSPM’s JSCOPR, Hadapsar, Pune-28

2. Mechanism of Action of
Cephalosporins
1 Cell Wall Disruption
Cephalosporins disrupt the synthesis of the bacterial cell wall by binding to
penicillin-binding proteins (PBPs), leading to weakening of the wall and
eventual cell lysis.
2 Resistance Prevention
Some newer generations of cephalosporins possess enhanced stability
against beta-lactamases, a mechanism used by bacteria to resist antibiotics.
3 Inhibition of Transpeptidation
They inhibit the transpeptidase enzyme, which is responsible for cross-linking
the peptidoglycan polymers during cell wall synthesis.
Prof. Sudha Unmesh Puri

3. Types of Cephalosporins
1 Generation-
Based
Classification
Cephalosporins are
grouped into
generations based
on their spectrum of
activity and clinical
use. These include
first, second, third,
and fourth-
generation
cephalosporins.
2 Structural
Classification
Structurally,
cephalosporins can
be classified based
on the presence or
absence of a
methylthiotetrazole
side chain.
3 Administration
Route
They can also be
classified based on
the route of
administration, with
oral and injectable
cephalosporins
being the most
common categories.
Prof. Sudha Unmesh Puri

4. Clinical Uses of Cephalosporins
Chemotherapy
Hospital-Acquired
Pneumonia
Certain cephalosporins,
especially third and
fourth-generation, are
effective in treating
hospital-acquired
pneumonia caused by a
variety of pathogens.
Skin and Soft Tissue
Infections
First and second-
generation
cephalosporins can be
used to treat skin and soft
tissue infections,
including cellulitis and
abscesses.
Intra-Abdominal
Infections
Third-generation
cephalosporins are used
for moderate to severe
intra-abdominal
infections, including
peritonitis and
cholecystitis.
Prof. Sudha Unmesh Puri

5. Side Effects and Adverse Reactions
of Cephalosporins
1 Allergic Reactions
Patients with a history of penicillin
allergy may experience cross-
reactivity to cephalosporins, leading
to allergic symptoms like rash, hives,
or, rarely, anaphylaxis.
2 Gastrointestinal Upset
Common side effects include
diarrhea, nausea, vomiting, and
abdominal discomfort due to the
disruption of normal gut flora.
3 Hematologic Effects
Some cephalosporins can cause hematologic abnormalities, such as leukopenia,
neutropenia, and thrombocytopenia, especially with prolonged use.
Prof. Sudha Unmesh Puri

6. Drug Interactions with
Cephalosporins
30+
Enzyme Inhibition
Certain cephalosporins can inhibit the
activity of liver enzymes, potentially leading
to the accumulation of other drugs
metabolized by the same enzymes.
20%
Protein Binding Displacement
Cephalosporins can displace other highly
protein-bound drugs, leading to increased
free drug levels and potential toxicity.
Prof. Sudha Unmesh Puri

7. Resistance to Cephalosporins
Microbial Mechanisms Bacteria can develop resistance through
enzyme production, alterations in
antibiotic targets, or decreased antibiotic
uptake.
Plasmid-Mediated Resistance Certain bacteria acquire resistance
genes on plasmids, making them
capable of producing enzymes that
inactivate cephalosporins.
Prof. Sudha Unmesh Puri

8. Strategies to Overcome Resistance
to Cephalosporins
Antibiotic
Stewardship
Promoting the
responsible use of
antibiotics can help
slow down the
development of
resistance, preserving
cephalosporins'
effectiveness.
Combination
Therapy
Using cephalosporins
in combination with
other antibiotics can
help combat resistance
by attacking bacteria
through different
mechanisms.
Research and
Development
Continued research is
vital to develop novel
cephalosporins that
can overcome existing
resistance
mechanisms employed
by bacteria.
Prof. Sudha Unmesh Puri

9. Spectrum of Activity of
Cephalosporins
Gram-Positive Bacteria
Certain cephalosporins are effective
against gram-positive organisms such as
Staphylococcus aureus and
Streptococcus pneumoniae, providing
coverage for skin and respiratory tract
infections.
Gram-Negative Bacteria
They have a broad spectrum, with third
and fourth-generation cephalosporins
being particularly effective against a wide
range of gram-negative bacteria,
including Pseudomonas aeruginosa and
Enterobacterales.
Prof. Sudha Unmesh Puri

10. Thank you for Your Attention
Thank you for taking the time to explore the fascinating world of
cephalosporins and their vital role in combating bacterial infections.
Prof. Sudha Unmesh Puri