Antibiotics

Question 1

What are the main mechanisms of antibiotic effectiveness & which groups work for each one

Answer 1

1. Cell wall disruptors - Beta lactams & Glycopeptides
2. Protein synthesis inhibitors - Macrolides, Chloramphenicol, Aminoglycosides, Tetracyclines
3. DNA inhibitors / interruptors - Rifampicin, Metranidazole, Quinalones
4. Anti-folate - Trimethoprim & Sulfonamides

Question 2

What are the 4 main classes of beta lactams

Answer 2

Penicillins
Monobactams
Cephalosporins
Carapenems

Question 3

Side effects of penicillin, amoxycillin

Answer 3

Penicillin allergy

Question 4

General uses of penicillins

Answer 4

Broad spectrum - respir. skin, UTI

Question 5

90% of staphylococcus produces something that makes beta lactams ineffective - what?

Answer 5

Beta lactamase e.g. penicillinase

Question 6

Many antibiotic resistant bacteria produce penicillinases - which drugs counter this?(3)

Answer 6

1. Co-amoxiclav (= amoxicillin & clavulanic acid)
2. Flucloxacillin (resist to penicillinases)
3. Tazobactam

Question 7

Are cephalosporins good for gram + or - bact

Answer 7

Gram negative

Question 8

Why would you be cautious administering cephalosporins to someone with penicillin allergy

Answer 8

10% of penicillin allergic folk also allergic to cephalosporins

Question 9

Cefuroxime is good for which pneumonia causing bacteria

Answer 9

Haemophilus influenzae

Question 10

Cefotaxime, ceftriaxome and poss. others are used in meningitis because?

Answer 10

They can cross the blood brain barrier

Question 11

What is a powerful glycopeptide useful for gram + bacteria

Answer 11

Vancomycin

Question 12

What virulent bacteria might vancomycin be good for (3)

Answer 12

MRSA
C diff
(& beta lactam resistant bact)

Question 13

Maj side effects of vancomycin (3)

Answer 13

Nephro toxicity
Ototoxicity
Red man / red neck syndrome

Question 14

Macrolides good for intracellular or extracellular infections?

Answer 14

Intracellular

Question 15

Examples of macrolides

Answer 15

Erythro, clarithro, azithromycin (“macro = mycin the MACRO mouse!”

Question 16

Which classic gram + bact are macrolides good for

Answer 16

Staph and strep

Question 17

What area of body macrolides good for (name 4 bacteria that might cause pathology there)

Answer 17

Chest - Legionella, Haemophilius influenzae, Mycoplasma, Neisseria

Question 18

When would you use aminoglycosides and what route of administration

Answer 18

Serious illness only - IV

Question 19

eg of aminoglycosides

Answer 19

Gentamicin

Tobramicin

Question 20

SE of aminoglycosides eg Gentamicin

Answer 20

Nephro & oto toxicity - v narrow therapeutic range

Question 21

Give 1 Gram - and 1 Gram + bact that aminoglycosides eg Gentamicin might be effective against

Answer 21

+ Staph

- Pseudomonas

Question 22

Tetracyclines e.g. doxycycline - maj side effects (2)

Answer 22

GIT irrit

Photosensitivity

Question 23

Two groups of people not appropriate for tetracyclines

Answer 23

Pregnant women

Kids

Question 24

Tetracyclines intra or extra cellular

Answer 24

Intracellular

Question 25

Area of body effective for tetracyclines (2)

Answer 25

Skin / tissue and CA pneumonia

Question 26

Chloramphenicol - uses other than eye ointment?

Answer 26

Serious illness only

Question 27

Gen type and some egs of side effects of chloramphenicol (3)

Answer 27

Multiple - haematological, anaemia, leukaemia

Question 28

Trimethoprim - main use as first line?

Answer 28

UTIs

Question 29

Rare SE of Trimethoprim

Answer 29

Rare but red. haematopoesis due to red folate

Question 30

Main combination of sulfonamide and trimethoprim

Answer 30

Co-trimoxazole

Question 31

Uses for co-trimoxazole

Answer 31

Immunocompromised - AIDs / toxoplasmosis

Question 32

SE of co-trimoxazole (2)

Answer 32

``` Skin probs (allergy) - Stevens-Johnson syndrome (nasty) Bone marrow depression ```

Question 33

Quinalones (eg Ciprofloxacin) - aerobic / anaerobic bact?

Answer 33

Anaerobic

Question 34

Ciprofloxacin has particularly good penetration of which tissues (3)

Answer 34

Bone marrow, CSF, skin

Question 35

Side effects of ciprofloxacin

Answer 35

Caution in epilepsy - siezures

Question 36

Interactions of ciprofloxacin

Answer 36

Metals - Ca, Fe suppliments red. absorption | Warfarin interactions

Question 37

Metranidazole - aerobic or anaerobic

Answer 37

anaerobic - good for abscesses, GIT, brain, liver

Question 38

Interactions of metranidazole

Answer 38

Alcohol

Question 39

Rifampicin - good for which bact (3)

Answer 39

TB! Neisseria MRSA

Question 40

What do you always do if using rifampicin

Answer 40

use a 2nd antibiotic too

Question 41

Interactions of rifampicin

Answer 41

CYP450 interactions (rifampicin isINDUCER)

Question 42

SE of rifampicin (2)

Answer 42

orange secretions | Liver toxicity