Antibiotic therapy Flashcards
What are the two types of antibiotics?
- Bacteriostatic- inhibit bacterial growth 2. Bacteriocidal- kill bacteria. Antibiotics can be narrow or broad spectrum. The ideal antibiotic- has selective toxicity/ minimal toxicity to the host
Antibiotics are most commonly administered _ or _ but sometimes also _
Orally, IV, IM
What parts of a cell does an antibiotic target?
- Cell wall 2. Ribosome 3. DNA replication 4. Metabolic pathways.
Cell wall synthesis is targeted by antibiotics like _ and _
Penicillins and glycopeptide antibiotics
What are examples of antibiotics that work on bacterial cell wall?
- Penicillin- (B lactam) 2. Cephalosporins (B lactam) 3. Glycopeptides (not b lactam)
Which penicillin is used for Gram + organisms?
Flucloxacillin
Which penicillins are used for Gram - & + organisms?
Amoxicillin, Co-amoxiclav, Tazocin
Penicillin used for Gram - organism?
Temocillin
Advantages of penicillin?
- Can be narrow & broad spectrum
- Safe, few side effects
- Rapidly excreted via kidneys
Drawbacks of penicillin?
- Some people can be allergic to it
- Needs frequent dosing due to rapid excretion
What are the 3 forms of penicillin? (dont memorise)
- Benzylpenicillin- IV
- PhenoxymethylP- Oral
- BenzathineP- IM, long acting
Flucloxacillin is a wide range penicillin. T/F?
False- narrow
Flucloxacillin typically help in _ and _ pathogen infections
Staphylocci and Streptococci
Amoxicillin has a wide range spectrum. T/F?
True- well tolerated, well abosrbed can be IV or Oral
Co-amoxiclav is amoxicillin + _ acid
Clavulanic
Co- amoxiclav is a wide spectrum antibiotic. T/F?
True
Tazocin is a narrow spectrum antibiotic. T/F?
False
Temocillin works best on pathogens like (hint Gram -)
- E coli
- Salmonella
- Enterobacter
Cephalosporins are very broad spectrum antibiotics but are hardly used due to dangeours side effects. T/F?
True
The use of Cephalosporins may promote the growth of which dangerous pathogen?
C.difficile
Mention a couple of adv & disad of B-lactam antibiotics.
- Advantage- safe, wide to narrow spectrum
- Disad- can cause hypersensitivity, rapidly excreted.
Two examples of Glycopeptides?
- Vancomycin
- Teicoplanin
Glycopeptides are bactericidal antibiotics. T/F?
True
Vancomycin is effective against Gram + bacteria. T/F?
True
Antibiotics that inhibit protein synthesis do so by attaching to bacterial _
Ribosomes
Antibiotics targetting protein synthesis are bactericidal. T/F?
False- Bacteriostatic, i.e. inhibit growth while being used.
What are some common antibiotics that target pathogen protein synthesis?
- Macrolides- Erythromycin
- Tetracyclin- Deoxycycline
- Aminoglycosides- Gentamicin
Mention a side effect for each of the following
- Aminoglycosides
- Tetracyclines
- Macrolides
a) Kidney damage
b) Destroys normal intestinal flora- infection
c) None
Give an example of an antibiotic that inhibits nucleic acid syntehsis
Metronidazole-commonly used against Ananerobes and some parasites
Cirprofloxacin is an example of a _
Quinolone
What are the commonest side effects of most antibiotics?
Nausea, vomiting, diarrhoea
Broad spectrum- greater risk of getting C difficile infection
What are the 3 common antibiotics that act on the bacterial cell wall?
- Penicillins (B lactam)- resembles D-alanine peptide and irreversibly binds, suicide Substrate
- Glycopeptides- binds to ends of peptide side chains and prevents its incorporaton into cell wall.
- Cephalosporins- inhibit cell wall synthesis. Bactericidal
