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Flashcards in Chapter 6: Antibiotics Deck (74):
1

Kills and inhibits organisms on body

Antiseptic

2

Kills and inhibits organisms on inanimate objects

Disinfectant

3

All organisms killed

Sterilization

4

Antiseptic: good for GPCs and GNRs; poor for fungi

Iodophors (Betadine)

5

Antiseptic: good for GPCs, GNRs, and fungi

Chlorhexidine gluconate (Hibiclens)

6

Inhibitors of cell wall synthesis

Penicillins, cephalosporins, carbapenems, monobactams, vancomycin

7

Inhibitors of the 30S ribosome and protein synthesis

Tetracycline, aminoglycosides (tobramycin, gentamicin), linezolid

8

Inhibitors of the 50s ribosome and protein synthesis

Erythromycin, clindamycin, Synercid

9

Inhibitor of DNA helicase (DNA gyros)

Quinolones

10

Inhibitor of RNA polymerase

Rifampin

11

Produces oxygen radicals that breakup DNA

Metronidazole (Flagyl)

12

- PABA analogue
- Inhibits purine synthesis

Sulfonamides

13

- Inhibits dihydrofolate reductase which inhibits purine synthesis

Trimethoprim

14

Bacteriostatic antibiotics

Tetracycline, clindamycin, erythromycin (all have reversible ribosomal binding), Bactrim

15

Have irreversible binding to ribosome and are considered bactericidal

Aminoglycosides

16

Mechanism: penicillin resistance

Due to plasmids for beta-lactamase

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MC method of antibiotic resistance

Transfer of plasmids

18

Resistance caused by a mutation of cell wall-binding protein

Methicillin-resistant S. aureus (MRSA)

19

Resistance caused by a mutation in cell wall-binding protein

Vancomycin-resistant enterococcus (VRE)

20

Resistance due to modifying enzymes leading to a decrease in active transport of this antibiotic into the bacteria

Gentamicin resistance

21

Vancomycin
- Peak
- Trough

Vancomycin
- Peak: 20-40 ug/mL
- Trough: 5-10 ug/mL

22

Gentamicin
- Peak
- Trough

Gentamicin
- Peak: 6-10 ug/mL
- Trough:

23

What if the peak is too high?

Decrease amount of each dose

24

What is the trough is too high?

Decrease frequency of doses (increase time interval between doses)

25

Antibiotics for:
- GPCs: streptococci, syphilis, Neisseria meningitides (GPR), Clostridium perfringens (GPR), beta-hemolytic Streptococcus, anthrax
- Not effective against Staphylococcus or Enterococcus

Penicillin

26

Antibiotics: anti-staph penicillins (staph only)

Oxacillin and nafcillin

27

Antibiotics: same as penicillin but also picks up enterococci

Ampicillin and amoxicillin

28

Antibiotics:
- Broad spectrum: pick up GPCs (staph/strep), GNRs +/- anaerobic coverage.
- Effective for enterococci; not effective for Pseudomonas, Acinetobacter, or Serratia

Unasyn (ampicillin/sulbactam)

Augmentin (amoxicillin/clavulanic acid)

29

Ampicillin / sulbactam

Unasyn

30

Amoxicillin / clavulanic acid

Augmentin

31

Beta-lactamase inhibitors

Sulbactam and clavulanic acid

32

- Antipseudomonal penicillins
- GNRs: enterics, pseudomonas, acinteobacter, serratia
- Side effects: inhibits platelets; high salt load

Ticarcillin and piperacillin (antipseudomonal penicillins)

33

- Broad spectrum: pick up GPCs (staph/strep), GNRs, anaerobes
- Effective for enterococci; effective for pseudomonas, acinetobacter, serratia
- SE: inhibits platelets, high salt load

Timentin (ticarcillin/clavulanic acid)

Zosyn (piperacillin/sulbactam)

34

Ticarcillin / clavulanic acid

Timentin

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Piperacillin / sulbactam

Zosyn

36

- GPCs: staph and strep
- Not effective for Enterococcus; does not penetrate CNS

First generation cephalosporins (cefazolin, cephalexin)

37

Why is ancef (cefazolin) good for prophylaxis?

It has a long half life.

38

- GPCs, GNRs, +/- anaerobic coverage; lose some staph activity.
- Not effective for enterococcus, pseudomonas, acinetobacter, serratia
- Effective only for community-acquired GNRs

Second-generation cephalosporin (cefoxitin, cefotetan, cefuroxime)

39

Why is cefotetan good for prophylaxis?

It has a long half life.

40

- GNRs mostly, +/- anaerobic coverage.
- Not effective for enterococcus; effective for pseudomonas, acinetobacter, and serratia
- Side effects: cholestatic jaundice, sludging in gallbladder (ceftriaxone)

Third-Generation cephalosporin (ceftriaxone, ceftazidime, cefepime, cefotaxime)

41

Antibiotics: GNRs, picks up pseudomonas, acinetobacter, serratia

Monobactam (aztreonam)

42

Antibiotics:
- Given with cilastin
- Broad spectrum: GPCs, GNRs, and anaerobes
- Not effective for MEP: MRSA, Enterococcus, Proteus
- Side effects: seizures.

Carbapenems (meropenem, imipenem)

43

Why are carbapenems given with cilastin?

Prevents renal hydrolysis of the drug and increase half-life

44

What are carbapenems not effective for?

MEP
- MRSA, Enterococcus, and Proteus

45

- GNRs, +/-GPCs
- Not effective for enterococcus, pseudomonas, acinetobacter, serratia
- Side effects: teratogenic, allergic reactions, renal damage, SJS, hemolyis in G6PD

Bactrim (TMP/SMX)

46

Trimethoprim / sulfamethoxazole

Bactrim

47

- Some GPCs, mostly GNRs
- Not effective for enterococcus, picks up Pseudomonas, acinetobacter, serratia
- 40% of MRSA sensitive; some efficacy PO and IV.

Quinolones (Ciprofloxacin, levofloxacin, norfloxacin)

48

- GNRs
- Good for pseudomonas, acinetobacter, and serratia; not effective for anaerobes (need O2)
- Synergistic with ampicillin for Enterococcus
- Beta-lactams (ampicilin, amoxicililn) facilitate penetration
- Side effects: reversible nephrotoxicity, irreversible ototoxicity

Aminoglycosides (gentamicin, tobramycin)

49

What is amino glycoside resistance secondary to?

Resistance due to modifying enzymes leading to decreased active transport

50

- GPCs, best for community-acquired pneumonia and atypical pneumonias
- Side effects: nausea (PO), cholestasis (IV)
- Also binds motilin receptor and is pro kinetic for bowel

Erythromycin (macrolides)

51

- GPCs, Enterococcus, Clostridium difficile (with PO intake), MRSA)
- Binds cell wall proteins
- Side effects: HTN, Redman syndrome (histamine release), nephrotoxicity, ototoxicity

Vancomycin (glycopeptides)

52

What is resistance to vancomycin (glycopeptides) due to?

Resistance develops from a change in cell wall-binding protein

53

- GPCs, includes MRSA, VRE

Synercid (streptogramin - quinupristin-dalfopristin)

Linezolid (oxazolidinones)

54

- GPCs, GNRs, syphilis
- Side effects: tooth discoloration in children

Tetracycline

55

- Anaerobes, some GPCs
- Good for aspiration pneumonia
- Can be used to treat C. perfringens
- Side effects: pseudomembraneous colitis

Clindamycin

56

- Anaerobes
- Side effects: disulfiram-like reaction, peripheral neuropathy (long-term use)

Metronidazole (Flagyl)

57

Antifungal: binds sterols in wall and alters membrane permeability
- Side effects: nephrotoxic, fever, hypokalemia, hypotension, anemia
- Liposomal type has fewer side effects

Amphotericin

58

Antifungal: inhibit ergosterol synthesis (needed for cell membrane)

Voriconazole
Itraconazole

59

Antifungal: inhibits synthesis of cell wall glucan

Anidulafungin (Eraxis)

60

Prolonged broad-spectrum antibiotics +/- fever

Itraconazole

61

Tx: invasive aspergillosis

Voriconazole

62

Tx: candidemia

Anidulafungin

63

Tx: fungal sepsis other than cadida and aspergillus

Liposomal amphotericine

64

Tuberculosis drugs

RIPE: rifampin, isoniazid, pyrazinamide, ethambutol

65

TB: inhibits mycolic acids (give with pyridoxine
-Side effects: hepatotoxicity, B6 deficiency

Isoniazid

66

TB: inhibits RNA polymerase
-Side effects: hepatotoxicity, GI symptoms, high rate of resistance

Rifampin

67

TB:
-Side effect: hepatotoxcity

Pyrazinamide

68

TB:
- Side effect: retrobulbar neuritis

Ethambutol

69

Inhibits viral DNA polymerase; used for HSV infections, EBV

Acyclovir

70

Inhibits viral DNA polymerase; used for CMV infections
- Side effects: decreased bone marrow, CNS toxicity

Ganciclovir

71

Broad spectrum antibiotics can lead to...

Superinfection

72

Antibiotics effective for enterococcus

Vancomycin
Timentin / Zosyn
Ampicillin / amoxicillin
Gentamicin w/ ampicillin

73

Effective for Pseudomonas, Acinetobacter, Serratia

Ticarcillin / piperacillin
Timentin / Zosyn
Third generation cephalosporins
Aminoglycosides (gentamicin and tobramycin)
Meropenem / imipenem
Fluoroquinolones

74

Purpose of perioperative antibiotics

- Used to prevent surgical site infections
- Need to be given within 1 hour before incision