Major groups of antimicrobials

Question 1

Give some examples of beta lactams? How does it work?

Answer 1

Inhibits bacterial wall synthesis

Penicillin, Cephlasporins (e.g. Ceftriaxone), Carbapenems (e.g.Meropenem)

Question 2

Give an example of a Quinolone? How does it work?

Answer 2

Ciprofloxacin

Inhibits DNA synthesis

Question 3

Give an example of a macrolide? How does it work?

Answer 3

Erythromycin

Inhibits protein synthesis in ribosomes

Question 4

Give an example of an aminoglycoside? How does it work?

Answer 4

Gentamycin

Inhibits protein synthesis in ribosomes

Question 5

Give an example of a glycopeptide? How does it work?

Answer 5

Vancomyocin

Inhibits cell wall synthesis

Question 6

Give an example of a tetracycline? How does it work?

Answer 6

Oxytetracycline

Works by inhibiting protein synthesis in the ribsomes

Question 7

Give an example of folate antagonists? How do they work?

Answer 7

Trimethoprim

Works by inhibiting DNA synthesis

Question 8

Give an example of Imidazoles? How do they work?

Answer 8

Metronidazole

Works by inhibiting DNA synthesis

Question 9

How do beta lactam antibiotics work? How resistance developed against them?

Answer 9

They work by producing a beta lactam ring that blocks the formation of petidoglycan cross-links in the bacterial cell wall. Bacteria have started to produce beta lactamase enzymes which cause resistance.
To overcome this some penicillins have been combined with beta lactamase inhibitors e.g. co-amoxiclav

Question 10

Which antibiotic would be appropriate for a streptococcus pneumoniae infection?

Answer 10

Penicillins because they are very good at treating alpha haemolytic streptococci

Question 11

Which antibiotic would be appropriate for treating h.Influenzae or S.aureus

Answer 11

Co-amoxiclav because it contains amoxicillin and clavulanic acid which is a beta lactamase inhibitor and these bacteria produce beta lactamase

Question 12

Which antibiotic is best for treating S.Aureus?

Answer 12

Flucloxicillin

Question 13

What is the main risk with penicillin antibiotics?

Answer 13

Risk of hypersensitivity reactions which are rare but can cause angioneurotic oedema, this cannot be detected by skin changes

Question 14

As you move through the classes of cephalosporins what changes?

Answer 14

The earlier classes are better at treating staph aureus

Later classes transition to being better at treating enterobacteria and psuedonomas

Question 15

What are Carbapenems good for treating? Give an example of a Carbapenem?

Answer 15

They are good for treating gram negative bacilli forms of beta lactamases. An example of meropenem. It is used to treat alpha streps such as strep. pneumoniae

Question 16

What are glycopeptide antibiotics good for treating? Give an example?

Answer 16

Good for treating MRSA

An example is vancomycin

Question 17

What are quinolones good for treating? Give an example?

Answer 17

Good for treating gram positive and negative bacilli but not MRSA or streptococci
An example is Ciprafloxicin
Often used to treat resistant UTIs

Question 18

What are macrolides good for treating? Give an example?

Answer 18

Good against respiratory infections. This includes S.pneumoniae, β-haemolytic streptococci, S.aureus, and H.influenzae

Question 19

What are aminoglycosides good for treating? Give an example?

Answer 19

They are good for treating Staph aureus and pseudomonas

Main issue is nephrotoxicity

Question 20

What are tetracyclines used for? give an example?

Answer 20

They are used for chlymidia, COPD infections and acne. An example is oxytetracyline

Question 21

What is nitrofurantoin an example of and what is it used for?

Answer 21

It is a orphan antibiotic and is used for treating UTIs

Question 22

What is Chloramphenicol used for?

Answer 22

Orphan antibiotic used for