Anti-bacterial (B lactams) Flashcards Preview

Pharmacology > Anti-bacterial (B lactams) > Flashcards

Flashcards in Anti-bacterial (B lactams) Deck (25)
Loading flashcards...
1

What are B lactams broadly know to do in their anti-bacterial mechanism?

Inhibit bacterial cell wall synthesis

2

What four categories can B lactams be divided into?

1. Natural
2. B-lactamase resistant
3. Aminopenicillins
4. Anti-pseudomonal

3

Name two Natural B lactams.

1. Penicilin G (Benzylpenicillin)
2. Penicillin V (Phenoxymethyl-penicillin)

4

Name two B-lactamase resistant B lactams.

1. Cloxacillin
2. Flucloxacillin

5

Name two Aminopenicillin B lactams.

1. Ampicillin
2. Amoxicillin

6

Name one Anti-pseudomonal B lactam.

1. Piperacillin

7

How can Penecillin G (Bezylpenicillin) be administered?

- IV
- IM

8

How can Penecillin V (Phenoxymethyl-penicillin) be administered?

- Oral

9

How can Cloxacillin be administered?

- Oral
- IV
- IM

10

How can Flucloxacillin be administered?

- Oral

11

How can Ampicillin be administered?

- Oral
- Parenteral

12

How can Amoxicillin be administered?

- Oral
- IV
- IM

13

How can Piperacillin be administered?

- Parentral

14

What is the MOA for Natural B lactams (Penicillin V and Penicillin V)?

- Bactericidal
- Targets growth and replication phase
- Inhibits transpeptidase enzyme (defects and rupturing of cell membrane)

* B-lactamase sensitive
* Acid labile
* Penicillin V less active

15

What is the MOA for B-lactamase resistant B lactams (Cloxacillin and Flucloxacillin)?

- Bactericidal

* B-lactamase resistance
* Acid stable
* Less active than Penicillin G

16

What is the MOA for Aminopenicillin B lactams (Ampicillin and Amoxicillin)?

- Bactericidal
- Absorption decreased by food
- Broad spectrum
- Co-amoxiclav (amoxicillin + clavulanic acid = B-lactamse resistant as clavulanic acid inhibits B-lactamse)

* B-lactamase sensitive
* Acid stable
* Cloxacillin + ampicillin = extends spectrum (additive interaction)

17

What is the MOA for Anti-pseudomonal B lactams (Piperacillin)?

- Bactericidal

18

What spectrum is Penicillin G (Benzylpenicillin)?

- Gram +ve cocci
- Anaerobes
* Narrow spectrum

- Enterococci (less susceptible) - add aminoglycoside
- Prophylaxis: streptococcal infections, rheumatic fever recurrence and surgical procedures of patients with valvular heart disease
- Penecillin G = initial therapy for serious infections and syphilis

19

What spectrum is Penicillin V (Phenoxymethyl-penicillin)?

- Streptococcal tonsilitis / pharyngitis

- Less serious infections
- Follow up treatment after serious infections

20

What spectrum are B-lactamase resistant B lactams (Cloxacillin and Flucloxacillin)?

- Mild B-lactamase +ve staphylococcal infections

21

What spectrum are Aminopenicillin B lactams (Ampicillin and Amoxycillin)?

- Gram +ve (especially enterococci and listeria)
- Gram -ve (hydrophilic amino-side chain gives penetration)
* Resistant organisms

- Prophylaxis: infective endocarditis

22

What spectrum are Anti-pseudomonal B lactams (Piperacillin)?

- Pseudomonas aeruginosa
* Extended spectrum

- Gram -ve when synergistic with tazobactam (B-lactamase inhibitor) and Aminoglycosides

23

What are the adverse effects of Penicillin G (Benzylpenicillin)?

- Neurotoxic effects (convulsions)
- Hypersensitivity
- Crosshypersensitivity
- Mild GIT disturbances
- Neutropaenia and agranulocytosis
- Superinfections
- Bleeding (decreased platelet aggregation)
- Fluid retention

24

What are the contra-indications of Penicillin G (Benzylpenicillin)?

- Elderly
- Neonates
- Allergic patients

25

What are the drug interactions of Penicillin G (Benzylpenicillin)?

- Probenecid, allopurinol and COCP (do NOT mix in IV)
- Probenicid, procaine and benzathine (extend half-life)