EXAM #4: ANTIBIOTICS III Flashcards Preview

Pharmacology > EXAM #4: ANTIBIOTICS III > Flashcards

Flashcards in EXAM #4: ANTIBIOTICS III Deck (60):
1

What class of antibiotic is Clindamycin?

Protein synthesis inhibitor

2

What is the spectrum of specificity of Clindamycin?

Narrow--commonly used to treat strep and staph soft tissue infections

3

What is the MOA of Clindamycin?

- Blocks the 50S subunit
- Step 1 (A site)
- Also blocks translocation of the amino acid chain to the P site

4

What are the key adverse effects associated with Clindamycin?

GI disturbances esp. C. DIFF

5

What class of antibiotic is Chloramphenicol?

Protein synthesis inhibitor

6

What is the MOA of Chloramphenicol?

- Binds the 50S subunit
- Prevents peptide bond formation

7

What are the key adverse effects seen with Chloramphenicol?

1) Suppression of RBC production
2) Gray Baby Syndrome

8

What is Gray Baby Syndrome?

- Serious side effect of IV chloramphenicol administration in newborn
- Infants have immature UGT
- UGT is needed to metabolize the drug--concentrations become toxic

9

What is Cloramphenicol typically used to treat?

Serious infections such as Typhus and Rocky Mountain Spotted Fever

10

What are the three drugs used to treat "resistant" organisms?

Vancomycin
Linezolid
Daptomycin

11

What class of drug is Linezolid?

Protein Synthesis Inhibitor

12

What is the specificty of Linezolid?

Gram positive organisms

13

What is the MOA of Linezolid?

- Binds 50S subunit
- Binds the A-site

14

What is the key adverse effect associated with Linezolid?

Myelosuppression

15

What is the general pattern of specificity regarding the protein synthesis inhibitors?

Broad spectrum

16

What protein synthesis inhibitor is NOT broad spectrum?

Clindamycin

17

What antibiotic class do the Sulfonamides fall into?

DNA synthesis inhibitors

18

List the Sulfonamides.

Sulfadizine
Sulfamethoxazole
Sulfamethizole

19

What do you need to remember about the Sulfonamides?

Commonly used in conjunction with another class of antibiotics

20

What is the MOA of the Sulfonamides?

- Structurally, these drugs are similar to PABA
- Compete with endogenous PABA in DNA synthesis
- Prevent DNA synthesis

21

What are the key adverse effects seen with the Sulfonamides?

1) Hypersensitivity
2) Photosensitivty
3) Steven-Johnson Syndrome

****Think S-Skin****

22

What type of infections are the Sulfonamides commonly used to treat?

UTIs

23

What is the specificity of the Sulfonamides?

Broad

24

What general class of antibiotic are the Trimethoprims?

DNA synthesis inhibitor

25

What two drugs fall into the category of Trimethoprims?

Trimethoprim
Pyrimethamine

26

What is the spectrum of activity for Trimethoprim?

Gram negative bacteria

27

What is Trimethoprim commonly used to treat?

UTIs

28

What is the MOA of Trimethoprim?

Inhibitor of bacterial dihydrofolate reductase i.e. DNA synthesis inhibitor

29

What is the key adverse effect associated with Trimethoprim?

Bone marrow suppression
Megaloblastic anemia

30

How are Sulfamethoxazole and Trimethoprim commonly administered?

Together as TMP-SMX i.e. Bactrim

31

What is TMP-SMX commonly given for?

UTI and Prostatitis

32

What class of antibiotics do the Fluoroquinolones fall into?

DNA sythesis inhibitors

33

What drugs are Fluoroquinolones?

Norfloxacin
Ciprofloxacin
Levofloxacin
Ofloxacin
Gatifloxacin
Gemifloxacin
Moxifloaxcin

34

What is the specificity of the Fluoroquinolones?

Broad (gram positive and negative)

35

What is the MOA of the Fluoroquinolones?

Inhibition of Topoisomerase to disrupt the unwinding of DNA

36

What are the key adverse effects seen with the Fluoroquinolones?

1) GI disturbances
2) Bind divalent cations e.g. Ca++ and prevent absorptions
3) QT prolongation

37

What is the Group 1 Fluoroquinolones?

Norfloaxacin

38

What are the Group 2 Fluoroquinolones?

Ciprofloxacin
Levofloxacin
Ofloxacin

39

What type of organisms are best targeted by the group 2 Fluoroquinolones?

Gram negative

40

What are the Group 3 Fluoroquinolones?

Gatifloxacin
Gemifloxacin
Moxifloaxacin

41

What bacteria are best targeted by the Group 3 Fluoroquinolones?

Gram positive

42

What is the mechanism of action of Metronidazole?

Induction of DNA damage

43

What types of organisms can be treated with Metronidazole?

BOTH bacteria AND protozoa

44

What is unique about Metronidazole?

Pro-drug that must undergo reduction

45

What bacteria is Metronidazole used to treat?

Anaerobic bacteria b/c they contain the enzyme necessary for reduction i.e. activation

46

What is Metronidazole commonly used to treat?

C.diff --along with Vancomycin

47

What are the key adverse effects of Metronidazole?

1) GI disturbances
2) Disulfiram-effect; thus, patients should avoid alcohol on this drug

48

What the the MOA of Daptomycin?

- Binds to the membrane of the bacteria
- Forms a pore and causes membrane depolarization

*This is a bactericidal

49

What is the specificity of Daptomycin?

Similar to Vancomycin--useful against Gram positive organisms

50

What key adverse effect is associated with Daptoymcin?

MSK disturbances i.e.
1) Rhabdomyolysis
2) Mypoathy

51

What is the MOA of Polymyxin B?

Detergent that punches holes in the membrane structure

52

What is Polymyxin B specific for?

LPS i.e. it is used to treat Gram negative bacteria

53

How is Polymyxin B commonly used?

Topically, similar to Bacitracin

54

What mechanisms of resistance are associated with PCNs and Cephalosporins?

1) Beta-Lactamase
2) Alteration of the PBP binding to drug
2) Alteration in porin function

55

What mechanisms of resistance are associated with Aminoglycosides?

Expression of enzymes that alter the structure of the drug

56

What mechanisms of resistance are associated with Macrolides?

1) Drug efflux pump
2) Alteration in binding to the 50S subunit

57

What mechanisms of resistance are associated with Tetracyclines?

Drug efflux pump

58

What mechanisms of resistance are associated with Sulfonamides?

1) Less sensitive drug target (isozyme)
2) Increased synthesis of PABA
3) Use of alternate sources of folic acid

59

What mechanisms of resistance are associated with Fluoroquinolones?

1) Less sensitive drug target
2) Drug efflux pump

60

What mechanisms of resistance are associated with Chloramphenicol?

Expression of inactivating enzymes

Decks in Pharmacology Class (64):