Antibiotics (1/2)

Question 1

desirable goals when designing antibiotics

Answer 1

• a drug with few adverse side effects and drug interactions
• specifically toxic i.e. damages a specific organism and not the patients cells and tissues
• able to achieve high conc at site of infection
• long half life
• wide range of formulations (oral tablets, IV formula, topical creams)

Question 2

half life

Answer 2

is the time taken for the concentration of a drug within plasma to fall to a half of what its initial starting concentration was.

Question 3

how is half life determined

Answer 3

by how quickly the drug is eliminated (clearance) from the plasma and how widely it spreads within the tissues (volume of distribution).

Question 4

why is it good if antibiotic has a long half life

Answer 4

With antibiotics, the drug needs to stay active in the patient for as long as possible so it can work against the infection without needing repeat dosages. You can imagine this would be good for improving compliance in a patient’s treatment regime (e.g. only taking 3 tablets instead of 7) and would help in a hospital to reduce the workload of the staff having to re-administer or re-hang IV bags.

Question 5

how can e classify antibiotics

Answer 5

• if they are lethal to bacteria or slow/ stops growth and reproduction
• if it attacks a wide variety of bacteria or specific few
• the site of action on the bacteria
• chemical structure of the antibiotics

Question 6

if lethal to bacteria

Answer 6

bactericidal

Question 7

if slows/stops growth and reproduction

Answer 7

bacteriostatic

Question 8

attacks a wide variety

Answer 8

broad spectrum

Question 9

attacks a specific few

Answer 9

narrow spectrum

Question 10

name the four mechanisms of action

Answer 10

• inhibit cell wall synthesis
• inhibit cell membrane function
• inhibit protein synthesis
• inhibit nucleic acid synthesis

Question 11

which family of antibiotics inhibit cell wall synthesis

Answer 11

Beta- lacta,s

Glycopeptides

Question 12

which family of antibiotics inhibit protein synthesis

Answer 12

tetracyclines
aminoglycosides
macrolides

Question 13

which family of antibiotics inhibit cell membrane function

Answer 13

polymixins

Question 14

which family of antibiotics inhibit nucleic acid synthesis

Answer 14

quinolones

Question 15

name the Beta-lactams

Answer 15

Penicillins

Cephalosporins

Carbapenems

Question 16

name four penicillins

Answer 16

penicillin
amoxicillin
flucloxacillin
Co-amoxiclav

Question 17

name a cephalosporin

Answer 17

ceftriaxone

Question 18

name two carbapenemes

Answer 18

meorpenem

imipenem

Question 19

name the two glycopeptides

Answer 19

vancomycin

teicoplanin

Question 20

name the two tetracycline

Answer 20

tetracycline

doxycyline

Question 21

name the maercolide

Answer 21

erythromycin

Question 22

name the aminoglycoside

Answer 22

gentamicin

Question 23

name the quinolone

Answer 23

ciprofloaxin

Question 24

name 2 trimethoprim

Answer 24

trimethoprim

co-trimoxazole

Question 25

two broad categories of antifungals

Answer 25

polyenes

azoles

Question 26

name two polyenes

Answer 26

nystatin

amphotericin

Question 27

name an azole

Answer 27

fluconazole

Question 28

remember if an antibiotic begins with the letter C it usually carries a risk of

Answer 28

C.difficile infection

doesn’t apply to antibiotics starting with Co-

Question 29

Co- before an antibiotic indicates

Answer 29

extra component