Beta Lactams

Question 1

In order for Beta Lactams to exert their effects what do they need?

Answer 1

they need a growing bacterial culture

Question 2

Bacteriocidal or Bacteriostatic/ Relative or Absolute Selective Toxicity? for beta lactams?

Answer 2

Bacteriocidal and Absolute

Question 3

list three mechanisms of actions that apply to all beta lactams

Answer 3

1. irreversibly inhibit the transpeptidase reaction
2. Cause cell osmotic pressure of the bacteria to rise causing lysis
3. Activate autolysins which open up the cell wall during cell division

Question 4

Ways of resistance by organisms against beta lactam drugs

Answer 4

1. Beta Lactamses which can be chromosomal or plasmid based. They open the B-Lactam ring rendering it obsolete.
2. Ways of decreasing the binding to Penicillin binding protein (MRSA Staph aureus and epidermiditis)
3. Some gram negatives have the capacity to modify their porins so that the antibiotic cannot reach inside the cell
4. Efflux of the antibiotic

Question 5

List the four types of pencilins

Answer 5

1. Penicilin G and V(Oral)
2. Acid stable or antistaphylococcal penicilins
3. Extended Spectrum (Amoxicillin, ampicillin)
4. Antipseudomonal or ureido penicillin

Question 6

What are penicillin G and V used against

Answer 6

1. Meningococcal infections
2. Pneumococcal infections
3. Non resistant Staph aureus infections
4. Strept pneumonaie infections
5. Syphilis (Treponema Pallidum)
6. Clostridia perforingens
7. Actinomycetes

Question 7

What are the acid stable or antistaphylococcal penicillins called? Also what do they work against?

Answer 7

• Oxacillin, Cloxacillin, Dicloxacilin (isoxazolyl)

- penicillinase producing Staph Aureus

Question 8

What are the extended spectrum penicilins?

Answer 8

• amoxicillin, ampicillin
• used to treat gram positives and negatives
• Give if the person is suffering from meningitis and you are not sure which organism it is
• Listeria Monocytogenes
• Enterococcus Faecalis
• Proteus Mirabalis
• Salmonella and shigella
• H influenzae
• ecoli

Question 9

what are the antipseudomonal or ureido penicillins used against?

Answer 9

Piperacilin
and it is used against gram negative bacteria
Klebsiella and Pseudomonas aerugonosa, and serratia marcerens

Question 10

Which penicillins are generally given orally

Answer 10

penicillin V, amoxicilin, ampicillin and isoxozolyl

Question 11

which penicillins are given intravenously

Answer 11

piperacillin, methacilline and penicillin G