Antibiotics are agents which used in treatment of bacterial infections.

1. ANTIBIOTICS (Beta-Lactams)
NAME:-TAPAS KUMAR MANNA
STREAM:M-PHARM(PHARMACOLOGY)
YEAR:-1ST YEAR,2ND SEMESTER
REGD.NO.181892310017
ROLL NO.18920218001
C0LLEGE:DR.B.C.ROY COLLEGE OF PHARMACY
&AHS,DURGAPUR,WESTBENGAL,713206.

2. DEFINATION OF ANTIBIOTICS :-
• An antibiotic is a product produced by a microorganism or a similar substance
produced partially Or totally by chemical synthesis ,which in low concentration
that inhibits Or kill the growth of other microorganisms.
• Antibiotic is referred to as chemotherapy because it is selectively designed to
inhibit/kill the infective organism and to have no/minimal effect on the
recipient(HOST).
• N:B-Antibiotic does not cure Viral infections like COLD,FLU etc.

3. CLASSIFICATION OF ANTIBIOTICS :-
• According to CHEMICAL STRUCTURE, antibiotics are classified into
different categories such as :-
1.Beta-Lactams
2.Sulfonamides
3.Aminoglycosides
4.Chloramphenicol
5.Tetracyclines
6.Macrolides
7.Glycopeptides
8.Quinolones
9.Others

4. Pharmacology effect of ANTIBIOTICS on Bacteria
• Antibiotics have 2 properties such as:-
1.BACTERIOSTATIC i.e. Inhibits the growth of bacteria.
2.BACTERICIDAL i.e. Kills the growth of bacteria.
• Antibiotics have 3 important modes of action to inhibit/kill the bacteria such as:-
(1) Inhibition of bacterial cell wall synthesis.
(2) Inhibition of bacterial protein synthesis.
(3) Inhibition of DNA synthesis.

5. CONTINUE:-
2.PROTEIN SYNTHESIS INHIBITORS:-
Aminoglycosides(e.g.Gentamicin,Amikacin)
1.CELL WALL SYNTHESIS INHIBITORS:- Chloramphenicol
 Beta- Lactams (e.g. Penicillins , Cephalosporins)
Tetracyclines (e.g. Oxytetracycline,Doxycycline)
 Glycopeptides (e.g.Vancomycin,Vancins)
Macrolides (e.g. Clarithromycin,Azithromycin)
3.DNA SYNTHESIS INHIBITORS:-
 Sulfonamides (e.g. Sulfamethoxazole,Cotrimoxazole )
 Quinolones (e.g. Ofloxacin,Moxifloxacin )

6. CONTINUE:-

7. BETA-LACTAM Antibiotics:-
Defination:
Beta-Lactam antibiotics are agents which contain Beta-Lactam nucleus or ring
in their molecular structures.
These are used to treat the bacterial infections caused by susceptible organisms.
These are used in both Gram Positive and Gram Negative bacteria.
But,specifically well effective in gram positive bacteria.
Classification:
There are 4 main classes of Beta-lactam antibiotics such as;
1.PENICILLINS
2.CEPHALOSPORINS
3.MONOBACTAMS [Beta-Lactam ring]
4.CARBAPENEMS

8. HISTORY OF PENICILLIN :-
• In 1928,Scottish Biologist; ALEXANDER FLEMING discovered Penicillin from
laboratory of St.Mary`s Hospital Medical School,London.
• It was accidental discovery because he kept the bacteria known as
Staphylococcus aureus on petri dish. Later, he observed that the bacteria was
destroyed by a unknown organism which produced coincidently.
• Consequently, he tested that unknown organism which was fungus called as
Penicillium notatum.
• Then,penicillin was used in 2nd World War for which he was awarded by NOBEL
prize in 1945.
[Antibiotic was given to soldier to
treat bacterial infection.][Sir Alexander Fleming]

9. CLASSIFICATION:-
1.PENICILLINS: { penicillin was obtained from Penicillium notatum fungus.}
Examples:- ( i ) Penicillin-G (P)
Penicillin-V (O)
( ii ) Methicillin(P)
[replaced by Vancomycin due to bacterial resistance]
( iii ) Ampicillin(O/P)
Amoxicillin(O/P)
Ticarcillin(P)
Piperacillin(P)
Natural penicillins
Sem-isynthetic penicillin
Synthetic penicillins

10. CONTINUE:-
2.CEPHALOSPORINS:- { It was obtained from Cephalosporium acremonium fungus.}
 Overally, the Cephalosporins are structurally and functionally same to the
penicillin.
 They have the same MODE OF ACTION as penicillins.
 Most Cephalosporins are produced semisynthetically by the addition of side
chains to a Dihydrothiazine ring( 7-aminocephalosporanic acid ) which fused
with Beta-lactam ring.
Examples:- (i ) {more gram +ve, less gram –ve}
Cefazolin ( Parenteral )
Cefalotin ( parenteral ) (1st generation )
Cefalexin ( oral )

11. CONTINUE:-
(ii) {more gram –ve,less gram +ve}
Cefuroxime Sodium ( P )
Cefuroxime Axetil ( O ) 2nd generation
( iii ) {good in gram –ve}
Cefotaxime ( P)
widely used Ceftriaxone ( P) 3rd generation
Cefixime ( O)

12. CONTINUE:-
(iv) only parenteral due to polar in nature,having zwitter ion activity,used in hospital
acquired gram negative bacteria.
Example:-
Cefepime (P) 4th generation
(v) Selectively and Prescribed drug,very expensive,hospital and
community acquired gram positive bacteria.
Examples:-
Ceftobiprole ( P )
Ceftaroline ( P ) 5th generation

13. CONTINUE:-
3.MONOBACTAM:
It is combination of MONOCYCLIC and BETA- LACTAM which
effective in hospital acquired gram negative bacteria.It is expensive.
Example:- Aztreonam (P)
4.CARBAPENEMS:
It is combination of BETA-LACTAM ring and 5 CYCLIC ring which effective in
both gram positive and negative bacteria.
Examples:-
Imipenem (P)
Faropenem (O)

14. ACTION OF BETA- LACTAMS
ON ORGANISMS:-
CAUSATIVE
ORGANISMS
1.Staphylococcus aureus
2.Streptococcus pneumoniae
3.Neisseria gonorrhoeae
4.Klebsiella pneumoniae
5.Escherichia coli
6.Pseudomonas aeruginosa
GRAM STAIN
GRAM +VE
GRAM +VE
GRAM-VE
GRAM -VE
GRAM -VE
GRAM –VE
INFECTION
SITES
Skin , Respiratory tract
Respiratory tract , Ear
Penis, Vagina
Urinary tract
GIT, Respiratory tract
Ear , Urinary tract,RT
ANTIBIOTIC
CLASS
Penicillin
Penicillin , Cephalosporins
Penicillin ,Cephalosporins
Penicillin , Cephalosporins
Penicillin ,Cephalosporins
P,C,M,Carbapenem
EXAMPLS
(AGENTS)
Vancomycin ,
Amoxicillin+Clavulanic acid
Penicillin-G, Cefuroxime axetil
penicillin-g, cefuroximeaxetil
Piperacillin, cefixime
Amoxicillin + clavulanic acid,
ceftriaxone
Piperacillin+tazobactam,imipenem

15. Mechanism Of Action:-
• Bacterial cell wall consists of large number of PEPTIDOGLYCANS ( Mureins ) which
are polymers , made up of NAG(N-AcetylGlucosamine) and NAM(N-AcetylMuramic
acid) that alternatively arranged and joined together by Beta-1,4-glycosidic linkage.
{INSIDE CELL WALL}
STEP-1(formation of Park nucleotide)
UDP ( Uridine diphosphate) consists of NAM which is pentapeptide called as Park
nucleotide.
STEP-2(fusion of Park nucleotide)
NAG and NAM get joined by eliminating 2 UDP.
STEP-3(cross linking)
The L-lysine which is 3rd position of NAM at which Glycine 5 chain is attached, this
Glycine 5 chain is attached to neighbour NAM at 4th position of D-alanine in presence of
Penicillin Binding Proteins(PBPs) which is sub-group of transpeptidase enzyme ,
process is called Transpeptidation. finaly,this PBPs is blocked by Beta-lactams and
bacteria is died.

17. Resistance of B-lactams(penicillin,cephalosporins):-
• Many bacteria synthesize an enzyme is called as Beta-lactamase(penicillinase)
which breaks down the Beta-lactam ring,as a result of ,Beta-lactam antibiotics
get inactivated.
• Compounds have been developed to inhibit the Beta-lactamase is called as Anti-
Beta-lactamase enzyme to allow susceptable Beta-lactam antibiotics to be more
effective.
Examples:- i) CLAVULANIC ACID
ii) SULBACTAM
iii) TAZOBACTAM

18. Anti-Beta-lactamases combination with Beta-lactams:-
1. AMOXICILLIN+CLAVULANIC ACID ( AUGMENTIN )
2. AMPICILLIN+SULBACTAM ( UNASYN )
3. TICARCILLIN+CLAVULANIC ACID ( TIMENTIN )
4. PIPERACILLIN+TAZOBACTAM ( ZOSYN )
5. IMIPENEM+CILASTATIN ( CILASAFE )
{Cilastatin prolongs the action of Imipenem.}

19. AGENT INTERACTIONS:-
1. Beta- lactam like Penicillin-G is taken along with Probenecid in which antibiotic
blood levels gets increased, as a result of, prolong action is shown whereas
Chloramphenicol and Tetracycline reduce the action of Penicillin-G.
2.Piperacillin is taken along with Cephalosporins which shows synergistic
effect(enhance the activity) whereas Aminoglycoside inactivates the piperacillin.
3.Cefotaxime is concurrently used with Aminoglycosides and frusemide which
leads to nephrotoxicity whereas Probenecid increases the action of Cefotaxime.
ADVERSE EFFECTS OF BETA-LACTAM ANTIBIOTICS:-
According to Expert opinion , Beta-lactams are generally safe drugs and serious
adverse events are rare,but overdosing can create adverse effects.
I )Hypersensitivity reaction arises rashes , fever .
II)Nausea. IV)Diarrhoea. VI)Neurotoxicity.
III)Vomiting. V)Nephritis.

20. THANK YOU
FOR
YOUR TIME….