General Information on A/B

Question 1

Which b-lactams are synthetic drugs?

Answer 1

Carbapenem (Imipenem) and Monobactams (Aztreonam)

Question 2

Which A/B are protein synthesis 50S inhibitors?

Answer 2

Macrolides (Erythromycin)
Clindamycin
Chloramphenicol

Question 3

Which A/B are protein synthesis 30S inhibitors?

Answer 3

Tetracyclines and Aminoglycosides (gentamicin)

Question 4

What is the ADR that occurs from rapid administration of Vancomycin? Give the clinical features.

Answer 4

Red Man’s syndrome: Fever, Chills, Red Itchy Rash on the neck, or arms and face, Local Phlebitis at site of infusion, Hypotension

Question 5

Which A/B only acts on Gram Negative bacteria?

Answer 5

Monobactams (Aztreonam)

Question 6

Which A/B only acts on Gram Positive bacteria?

Answer 6

Antistaphylococcal Penicillins (Flucloxacillin)
Vancomycin

Question 7

Which A/B is not absorbed orally?

Answer 7

Vancomycin
Cephalosporins - poor oral absorption (except for Cefadroxil [1st gen] and Cefixime [3rd gen])
Monobactam? (administered IV or IM)
Carbapenem? (administered IV)

Question 8

How is cephalosporins excreted? Give the exception.

Answer 8

Excreted by tubular secretions and glomerular filtrations. Except for Ceftriaxone which is secreted via bile into faeces.

Question 9

How can penicillins be excreted?

Answer 9

Via renal clearance or in breast milk

Question 10

Doxycycline is classed as Tetracycline class D drugs. What is special about this class?

Answer 10

Doxycycline is contraindicated in pregnancy and for children below 8 years old.

Question 11

Is Flucoxacillin or Cefuroxime not appropriate for the treatment of UTI? Explain.

Answer 11

Flucloxacillin. It only targets Gram + bacteria and UTI can be caused by Gram - bacteria.

Question 12

Which component of Gram - bacteria acts as an endotoxin?

Answer 12

Lipopolysaccharide

Question 13

Which bacteria is usually the cause of rheumatic fever? When will rheumatic fever occur after the infection?

Answer 13

Group A Streptococcus commonly causes rheumatic fever. Occurs 2-4 weeks later after strep sore throat

Question 14

What food mustn’t be taken with Doxycycline? Explain.

Answer 14

Calcium/Dairy products and antacids/Mg2+ and Al3+

Calcium impairs/decreases absorption due to formation of non-absorbable chelates of tetracyclines.

Question 15

Which drug is the first choice alternative to penicillin in patients with allergy to beta lactam antibiotics

Answer 15

Macrolides (erythromycin)

Question 16

What is IV erythromycin associated with?

Answer 16

Thrombophlebitis

Question 17

Sulfonamides bind to which serum protein? Hence, what are the side effects of taking sulfonamides?

Answer 17

Sulfonamides bind to serum albumin.
Able to cause Warfarin potentiation as it displaces Warfarin from albumin and cause increased bioavailability of Warfarin.
Also causes Kernicterus (brain damage) due to bilirubin build up, as Sulfonamides can displace bilirubin from albumin.

Question 18

Which Macrolide has increased absorption with food?

Which Macrolide has decreased absorption with food?

Answer 18

Azithromycin and Erythromycin have decreased absorption with food.
Clarithromycin has increased absorption with food.

Question 19

Erythromycin and Clarithromycin are used to attack against which types of bacteria respectively?

Answer 19

Erythromycin is used against Gram + bacteria and spirochetes.
Clarithromycin is used against H. Influenza and H. Pylori.

Question 20

Which drug will lead to discoloration of teeth?

Answer 20

Tetracycline

Question 21

What type of bacteria does Gentamicin works against?

Answer 21

Aerobic Gram - bacteria, including P. Aeruginosa, or infections due to enterococci.
Aerobic Staphylococci

Question 22

Why can’t aminoglycosides be effective against Anaerobes?

Answer 22

Anaerobes do not have the O2 transporter system required for drugs to be transported into cells of bacteria.

Question 23

Which drug accumulates in the ears?

Answer 23

Gentamicin

Question 24

Give an example of Quinolone

Answer 24

Ciprofloxacin

Question 25

Which antibiotic is only able to act on aerobic bacteria cells? Why not anaerobes?

Answer 25

Aminoglycosides (Gentamicin) can only be used against Aerobic Gram - bacilli.
Anaerobes do not have the O2 transport system required for aminoglycosides to enter the bacteria.

Question 26

Which antibiotic acts on MRSA?

Answer 26

Vancomycin
Teicoplanin
Daptomycin
Linezolid

Question 27

Which antibiotics will work against Pseudomonas?

Answer 27

Piperacillin-Tazobactam (Tazocin)
Meropenem
Gentamicin
Ciprofloxacin

Question 28

Which antibiotics work against anaerobes?

Answer 28

Co-amoxiclav
Piperacillin-Tazobactam (Tazocin)
Meropenem
Metronidazole