Antibiotics are antimicrobial drugs used to treat bacterial infections, distinguishing between bactericidal (which kill bacteria) and bacteriostatic (which inhibit their growth). The document discusses the history, classification, mechanisms of action, side effects, and the development of antibiotic resistance, emphasizing the importance of responsible use to prevent the emergence of resistant bacteria. It covers various antibiotic classes including sulfonamides, penicillins, cephalosporins, tetracyclines, macrolides, aminoglycosides, and quinolones, along with their specific uses and associated adverse effects.

1. ANTIBIOTICS
Presented By:-
Mridul Chhokar
B.Pharmacy

3. DEFINATIONS
 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. A limited
number of antibiotics also possess antiprotozoal activity.
Antibiotics are not effective against viruses such as the common
cold or influenza, and their inappropriate use allows the
emergence of resistant organisms.

4. ACTIONS
Bactericidal = kill bacteria
Bacteriostatic = Inhibits growth of Susceptible
Bacteria, rather them killing them immediately will
eventually leads to Bacterial Death.

5. HISTORY
 In 1928, Alexander Fleming identified penicillin, the first
chemical compound with antibiotic properties. Fleming was
working on a culture of disease-causing bacteria when he
noticed the spores of a little green mold (Penicillium
chrysogenum), in one of his culture plates. He observed that
the presence of the mold killed or prevented the growth of
the bacteria.

6. Bacteria shapes
 Round cocci
 Rod like Bacillii
 Spiral shaped Spirochetes

7. CLASSIFICATION OF ANTIBIOTICS
 Sulfonamides
 Penicillin
 Cephalospoins Tetracyclins
 Macrolides
 Aminoglycosides
 Quinolones

8. HOW ANTIBIOTICS WORK
 Block protein formation.
 Macrolides
 Tetracycline
 Aminoglycosides
 Inhibits cell formation
 Interfere with DNA formation
 Nalidixic acid
 Prevent folic acid synthesis
 Sulfonamides

9. SULFONAMIDES
 One of the first group of antibacterial agents having
Bacteriostatic action.
 Prevent synthesis of folic acid.
 Does’nt effect human cells.
 TREAT:- Urinary Tract Infections.(URIs)

10. SULFONAMIDES: SIDE EFFECTS
 Anemia
 Thrombocytopenia
 Steven-Johnson syndrome
 Diarrhea
 Nausea
 Headache
 Urticaria

11. PENICILLIN
 First introduced in the 1940s
 Bactericidal: inhibits cell wall synthesis
 Kill a wide variety of bacteria
 Also called “beta-lactams”
 Prevention and treatment from infection caused by
susceptible bacteria such as :-
• Gram +ve bacteria

12. PENICILLIN
 Natural
Penicilllin G
Penicillin V
 Aminopenicillins
Amoxicillin
Ampicillin
 Penicillinase-resistant
Oxacillin
Nafcillin

13. MECHANISM OF ACTION
 Penicillin enters the bacteria via cell wall.
 Inside the cell , they bind to penicillin-binding protein.
 Once bound, normal cell wall synthesis was disrupted.
 Because of this bacteria dies from cell lysis.
 Penicllin do not kill other other cells in the body.

14. ADVERSE EFFECT
 Allergy
 Diarrhea
 Nausea

15. CEPHALOSPORINS
 Semisynthetic
 Related to penicillin
 Bactericidal
 4 generations

16. CEPHALOSPORINS
 Semisynthetic derivatives from a fungus
 Structurally and pharmacologically related
to penicillins
 Bactericidal action
 Broad spectrum
 Divided into groups according to their antimicrobial activity

17. CEPHALOSPORINS : USES
 Surgical prophylaxis
 URIs
 Otitis media

18. SIDE EFFECTS
 Allergy
Rash, swelling, itching

19. Tetracyclines
 Bind to Ca2+ and Mg2+ and Al3+ ions to
form insoluble complexes
 Thus, dairy products, antacids, and iron
salts reduce absorption of tetracyclines

20. Tetracyclines: uses
 Acne
 Chronic bronchitis
 Lyme disease
 Mycoplasma pneumoniae infection
 Rickettsia infection
 Some venereal diseases, such as Chlamydia infection
 Traveler’s diarrhea

21. ADVERSE EFFECT
 Discoloration of permanent teeth and tooth
enamel in fetuses and children
 May retard fetal skeletal development if taken
during pregnancy
 Diarrhea

22. MACROLIDES
 erythromycin
 azithromycin (Zithromax)
 clarithromycin (Biaxin)
 dirithromycin
 troleandomycin
bactericidal action

23. MACROLIDES: USES
 Strep infections
 Mild-to-moderate URIs
 Lyme disease
 STDs

24. SIDE EFFECTS
 Strep infections
 Mild-to-moderate URIs
 Lyme disease
 STDs

25. Aminoglycosides
 gentamicin (Garamycin)
 kanamycin
 neomycin
 streptomycin
 tobramycin
 amikacin (Amikin)
 netilmicin

26. AMINOGLYCOSIDES: USES
 Used to kill gram-negative bacteria such as Pseudomonas
spp., E. coli, Proteus spp., Klebsiella spp., Serratia spp.
 Often used in combination with other antibiotics for
synergistic effect.

27. ADVERSE EFFECT
Headache
Paresthesia
Neuromuscular blockade
Dizziness
Vertigo
Skin rash
Fever

28. QUINOLONES
 ciprofloxacin (Cipro)
 enoxacin (Penetrex)
 lomefloxacin (Maxaquin)
 norfloxacin (Noroxin)
 ofloxacin (Floxin)

29. QUINOLONES: USES
 Lower respiratory tract infections
 Bone & joint infections
 Infectious diarrhea
 UTIs
 Skin infections
 STDs
 Anthrax

30. SIDE EFFECTS
 HA
 N-V-D
 Allergic reaction

31. Antibiotic resistance
The ability of bacteria and other microorganisms
to resist the effects of an antibiotic to which they
were once sensitive. Antibiotic resistance is a
major concern of overuse of antibiotics. Also
known as drug resistance.
Therefore a great care should be taken before
taking antibiotics and it should be only taken on
the advice of Pharmacist or a Doctor.