wk6:AED - Antibacterial 2 Flashcards
Name 5 antibiotics that can be given orally
penicillin cephalosporin macrolides fluorooquinolones tetracyclines
How commonly is penicillin used in eye care?
rarely
How does penicillin work?
inhibits bacterial cell wall synthesis
Is penicillin bacteriostatic or cidal?
bactericidal
Are most staphylococci sensitive or resistant to penicillin?
resistant (they produce an enzyme penicillinase that degrades the clinical efficiency of penicillins)
What is special about dicloxacillin (in relation to penicillins)?
penicillinase resistant
What is amoxycillin?
is a classic synthetic penicillin
How can we improve the spectrum of activity of amoxycillin?
Combine with potassium clavulanate (a beta lactase inhibitor)
How does the spectrum of activity of amoxycillin-clavulanate compare with amoxycillin?
Extended coverage of gram positives, some gram negatives
How good of a choice is amoxycillin-clavulanate for common eye and eyelid infections?
excellent choice
What is the standard dosage of diicloxacillin treatment? Why?
250mg qid. due to short half life.
Is dicloxacillin taken with meals?
Doesn’t have to be
What are the standard doses for amoxycillin-clavulanate treatment? (3)
Depends on severity.
Mild = 500mg
Most = 875mg
Severe = 1000mg
List 6 potential side effects of penicillins
Hypersensitivity reactions Up to 20% reported Most limited to skin rashes Severe anaphylaxis (uncommon) May also alter normal flora in resp. tract (super infections) Gastrointestinal upset
What 3 alternative antibiotics might you use if your patint is allergic to pnicillin?
Cephalosporin
Macroliides
Fluoroquinolone
Name a common first choice ophthalmic antibiotic
Cephalosporin
What part of bacteria is targeted with cephalosporin tx?
Bacterial cell wall synthesis (so similar to penicillins)
Do cephalosporins contain a beta lactam group?
yes, but derived from different amino acids than the penicillin beta lactam group
How long is a standard course of cephalexin (a type of cephalosporin, also known as keflex)?
1 week (lenght can change based on severi or condition)
What is the usual dosage of cephalexin?
500mg bid or 500mg qid