The document discusses different classes of antibiotics, including penicillins, cephalosporins, carbapenems, macrolides, lincosamides, aminoglycosides, tetracyclines, fluoroquinolones, rifampin, metronidazole, and trimethoprim-sulfamethoxazole. It describes their mechanisms of action, spectrums of coverage, indications for use, and potential disadvantages or side effects. The document is authored by a 4th year medical student as part of a study on antibiotic classifications and properties.

1. Antibiotics
By :
Abdullah Taskin
-4th year med. Student -
BY : Abdullah Taskin 4th y.

2. • Classified according to their MOA into :
BY : Abdullah Taskin 4th y.

3. BY : Abdullah Taskin 4th y.

4. BY : Abdullah Taskin 4th y.

5. Penicillin's
1.
2.
3.
4.
5.
6.
7.
8.
Benzyl penicillin
Aminopenicillin (ampicillin IV - amoxicillin PO)
Isoxozoyl penicillin (cloxacillin, methicillin, )
Ureidopenicillin ( piperacillin )
Lactamase Inhibitors (Augmentin – tazobactam )
Cephalosporins ( 1 , 2 , 3 & 4 )
Carbapenems (imipenem )
Vancomycin (Vancocin®)
BY : Abdullah Taskin 4th y.

6. Coverage :
GP except
Staphylococcus,
Enterococcus
Oral anaerobes
(except
Bacteroides,
Treponema)
penicillin
MOA :
Bactericidal:
β-lactam inhibits
(PBP) and
prevents crosslinking of
peptidoglycans
BY : Abdullah Taskin 4th y.
Indications:
actinomycosis,
streptococcal
pharyngitis,
streptococcal
skin and soft
tissue infections,
syphilis
Contraindications:
Hypersensitivity to
penicillin

7. Coverage :
sam as
B.penicillin
MOA :
sam as
B.penicillin
Contraindications:
Hypersensitivity to
penicillin
Aminopenicillin
( Amoxicillin )
Indications:
bacterial meningitis ,
endocarditis ,
streptococcal ,
part of H. pylori treatment,
UTI
BY : Abdullah Taskin 4th y.

8. Coverage :
sam as B.penicillin
Isoxozoyl penicillin
(methicillin )
MOA :
sam as B.penicillin
Contraindications:
Hypersensitivity to
Penicillin
&
> Interstitial nephritis
Indications ( only diff. ) :
also cover some staph.a
BY : Abdullah Taskin 4th y.

9. Coverage :
sam as
B.penicillin
MOA :
sam as
B.penicillin
Ureidopenicillin
(Tazocin®)
Indications :
Same as penicillin &
GN: Pseudomonas
Anaerobes
Contraindications:
Hypersensitivity to
penicillin
Enterococcus
BY : Abdullah Taskin 4th y.

10. Coverage :
sam as B.penicillin
Lactamase Inhibitors
(Augmentin®)
MOA :
sam as B.penicillin
Contraindications:
Hypersensitivity to
Penicillin
&
jaundice or hepatic
dysfunction
Indications :
Same as penicillin
+/&
Staphylococcus
H. influenzae
Enterococcus
BY : Abdullah Taskin 4th y.

11. Cephalosporins ( 1 , 2 , 3 & 4 )
widely used
BY : Abdullah Taskin 4th y.

12. Coverage :
GP except
Enterococcus
Ceph.S. 1st
(cephalexin , cefazolin)
&
GN except
E. coli,
Klebsiella,
Proteus
MOA :
same as penicillin
(B-lactam)
Indications:
GP “more” & GN
Contraindications:
Hypersensitivity to Penicillin or ceha.S.
&
Nephrotoxicity
BY : Abdullah Taskin 4th y.

13. Coverage :
GP week
&
GN
&
anaerobes
MOA :
same as penicillin
(B-lactam)
Ceph.S. 2nd
(Ceftin®) , Cefprozil (Cefzil®))
Contraindications:
Hypersensitivity to
Penicillin or ceha.S.
BY : Abdullah Taskin 4th y.

14. Coverage :
GP
Staph & strep.
&
GN
broad
+ pseudomonas
MOA :
same as penicillin
(B-lactam)
Ceph.S. 3rd
(cefixime, ceftriaxone , cefotaxime
& ceftazidime )
Indications:
RTI, gonorrhea (use cefixime),
meningitis, septicemia,
abdominal infections
Contraindications:
Hypersensitivity to
Penicillin or ceha.S.
BY : Abdullah Taskin 4th y.

15. Coverage :
Ceph.S. 4th
(cefepime)
(good for gram
+ve and –ve)
&
pseudomonas
“penetrates the
CSF”
MOA :
same as penicillin
(B-lactam)
Contraindications:
Hypersensitivity to
Penicillin or ceha.S.
BY : Abdullah Taskin 4th y.

16. Cephalosporins (β-Lactam) :
a) Renal elimination
b) Ceftriaxone & Cefoperazone biotransformation in the liver.
c) Thrombocytopenia associated with cefamandole and
cefoperazone NOT cefotetan!!
d) Pyrogenic (highest rates of drug induced fever)
BY : Abdullah Taskin 4th y.

17. Coverage :
GN only
&
work with
aminoglycosides
MOA :
(B-lactam)
Monobactams β-Lactam Aztreonam
Indications:
patients who are allergic to penicillins
or cephalosporins
Contraindications:
Not allergic .
BY : Abdullah Taskin 4th y.

18. Coverage :
GP except
Enterococcus,
MRSA
GN including
Pseudomonas
+ Enterobacter
Anaerobes
MOA :
(B-lactam)
Carbapenams β-Lactam:
(Imipenam )
Indications:
LARGEST SPECTRUM OF ACTIVITY of any B-lactam
Rx: Septicemia of unknown origin
Major disadvantages:
metabolize by kidney > cause decreased urinary
concentration. SE: seizers ,rash
so IMIPENAM + CILASTATIN (inhibitor of
enzyme) are given
together.
BY : Abdullah Taskin 4th y.

19. Coverage :
GP except
Enterococcus,
MRSA
GN including
Pseudomonas
+ Enterobacter
Anaerobes
Carbapenams β-Lactam:
(meropenem )
Major disadvantages:
not need CILASTATIN
&
Less seizures
MOA :
(B-lactam)
BY : Abdullah Taskin 4th y.

20. Coverage :
NON β-Lactam:
( VANCOMYCIN )
GP (strong)
MOA :
Indications:
GP: (RESISTANT to methicillin)
e.g. MRSA & MRSE
must be given IV NO GI
Glycopeptide
stearically
inhibits addition of
peptidoglycan
subunits
Major disadvantages:
Red Man Syndrome
, Nephrotoxicity , Ototoxicity , Neutropenia,
Thrombocytopenia
BY : Abdullah Taskin 4th y.

21. NON β-Lactam:
(FOSFOMYCIN )
Coverage :
Gram +ve and –
ve spectrum
MOA :
Indications:
SINGLE DOSE Of uncomplicated UTI :
treatment of ONLY IN
FEMALES!!
inhibit cell wall
BY : Abdullah Taskin 4th y.

22. Contraindicated in pregnancy
1. Aminoglycosides
2. Erythromycin
3. Clarithromycin
4. Tetracyclines
5. Fluoroquinolones
BY : Abdullah Taskin 4th y.

23. Protein synthesis inhibitors :
BY : Abdullah Taskin 4th y.

24. 50 S
A- Macrolides
Protein synthesis
inhibitors
B- Lincosamides
1) Erythromycin
1) clindamycin
2) clarithromycin
2) Chloramphenico
3) azithromycin
3) linezolid
BY : Abdullah Taskin 4th y.
30 S
1- Aminoglycosides
2- Tetracyclines

25. Macrolides
Coverage :
GP except
Enterococcus
&
GN
“Atypicals”
MOA :
inhibit 50 S
Indications:
Clarithromycin = H.pyloric
Azithromycin = Co-drug of choice for
Chlamydia & Safe in pregnancy .
Major disadvantages:
GI upset , acute cholestatic hepatitis
Prolonged QT
Hypersensitivity
BY : Abdullah Taskin 4th y.

26. clindamycin
Coverage :
GP except
Enterococcus
&
Anaerobes
MOA :
inhibit 50 S
clindamycin =Pseudomembranous
colitis
Chloramphenicol= Aplastic anemia &
Grey baby syndrome
linezolid = HTN , myelosuppression
optic neuropathy,
peripheral neuropathy
BY : Abdullah Taskin 4th y.

27. Aminoglycosides
Coverage :
GN &
psudomonas
MOA :
inhibit 30 S
Indications:
G - & no alternatives .
Major disadvantages:
Nephrotoxicity
Ototoxicity
BY : Abdullah Taskin 4th y.

28. Coverage :
GP
Anaerobes
Atypicals:
Chlamydophila,
Mycoplasma,
Treponema
prophylaxis
MOA :
inhibit 30 S
Tetracyclines
Indications:
Rickettsial infections,
Chlamydophila, acne
malaria
prophylaxis (doxycycline).
Major disadvantages:
Hepato-renal toxicity, Fanconi’s syndrome,
Photosensitivity, Teratogenic, Yellow teeth and
stunted , Taskin 4th y. growth in children,( not in preg.)
bone
BY : Abdullah

29. Coverage :
Poor GP activity
GN
Atypicals
FIncludes anaerobes
No Pseudomonas
coverage
TOPOISOMERASE INHIBITORS :
Fluoroquinolones
Indications:
Only use when necessary
to prevent resistance
except : ciprofloxacin
MOA :
Inhibits DNA gyrase
Dysglycemia
Major disadvantages:
Allergy , Seizures , Prolonged QT
BY : Abdullah Taskin 4th y.

30. Coverage :
GPC
N. meningitidis
H. influenza
Mycobacteria
MOA :
Inhibits RNA
polymerase
TOPOISOMERASE INHIBITORS :
Rifampin
Indications:
TB , latent TB , Endocarditis
& prophlaxis N. meningitides exposure
Major disadvantages:
Hepatic dysfunction, P450, Orange
tears/saliva/urine & Jaundice
BY : Abdullah Taskin 4th y.

31. Coverage :
Anaerobes
Protozoa
MOA :
Forms toxic
metabolites in
bacterial cell which
damage
microbial DNA
TOPOISOMERASE INHIBITORS :
Metronidazole (Flagyl®)
Indications:
Protozoal infections
(trichomonas, amebiasis,
giardiasis), bacterial
vaginosis, anaerobic bacterial
infections
Major disadvantages:
Seizures
Peripheral neuropathy ,
BY : Abdullah Taskin 4th y.

32. Coverage :
GP
GN: enteric
Nocardia
Other: Pneumocystis,
Toxoplasmosis
MOA :
Inhibits folic acid
production
(TMP inhibits DHFR and
SMX is a competitive
inhibitor of PABA)
ANTI-METABOLITE:
Trimethoprim- Sulfamethoxazole
(TMP/SMX)
Major disadvantages:
Hepatitis , Stevens Johnson syndrome
TMP:
- Megaloblastic anemia
- Leuko/granulocytopenia
- Hyperkalemia
SMX:
- Hypersensitivity
- Interstitial nephritis
- BM suppression
BY : Abdullah Taskin 4th y.

33. Remain :
• Antimyobacterial ( rifampicin covered above )
BY : Abdullah Taskin 4th y.

34. Appendix
BY : Abdullah Taskin 4th y.

35. Basic : G.ngative vs. G.positive
BY : Abdullah Taskin 4th y.

36. BY : Abdullah Taskin 4th y.

37. Properties of penicillin :
• All penicillin has Beta lactam ring .
• Trans-peptidase or (penicillin-binding protein)
• Function : Synthesis of peptidoglycan layer .
• To be effective Penicillin must :
I. Penetrate cell layer
II. Keeps it beta lactam ring intact
III.Bind to Trans-peptidase .
BY : Abdullah Taskin 4th y.

38. How bacteria defended from penicillin ?
In three ways :
1) G. negatives prevent penetration of
cell layers by
alteration of porins.
2)G. negatives destroy beta-lactam in periplasmic space
.
3) Bacteria inhibit binding of B.lactam
to transpeptidase by altering structure of Trans-peptidase .
BY : Abdullah Taskin 4th y.

39. References :
• Ananthanarayan & Pinker’s 8th edition .
• Clinical Microbiology Made Ridiculously Simple – 3rd edition
BY : Abdullah Taskin 4th y.

40. Thank you …
BY : Abdullah Taskin 4th y.

41. BY : Abdullah Taskin 4th y.