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Pharmacology II Final Exam > Intro to Antibiotics > Flashcards

Flashcards in Intro to Antibiotics Deck (46)
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1

What is a broad spectrum antibiotic?

It is active against gram positive AND gram negative bacteria and it increases resistance.

2

What is a narrow spectrum antibiotic?

It is active against gram positive OR gram negative.

3

What does bactericidal mean?

- Kills bacteria
- Reasonably achievable tissue concentration that is greater than the minimum bactericidal concentration (MBC.)

4

What does bacteriostatic mean?

- Stops growth or replication of bacteria
- Reasonably achievable tissue concentration that is greater than the minimal inhibitory concentration (MIC.)

5

What do you need for a bacteriostatic drug to work?

You need a competent immune system.

6

What does MIC stand for?

Minimal Inhibitory Concentration

7

What does MBC stand for?

Minimum Bactericidal Concentration

8

When are time-dependant antibiotics most effective?

When the level of drug remains above a certain cut-off for a significant portion of the day.

9

T > MIC is greater than _____% of the dose interval?

40 - 50%

10

When are concentration-dependant antibiotics most effective?

When a high leave of the drug is reached, often above an absolute cut-off. Does not need to be maintained for any specific amount of time.

11

What does PAE stand for?

Post - Antibiotic Effect

12

Concentration-dependant drugs have a ______ that causes continued organism suppression even after drug levels drop.

Post - Antibiotic Effect

13

Cmax / MIC > ______?

8-12

14

What is the "third - category" of dose - dependent drugs?

Some drugs have efficacy correlated with total body exposure to the drug (estimated by the AUC.)

AUC / MIC > 125

15

What does AUC stand for?

Area Under the Curve

16

What are the MOA of x-dependent drugs? (4)

1. Inhibition of cell wall synthesis
2. Disruption of cell membranes
3. Inhibition of protein synthesis
4. Inhibition of DNA synthesis / function

17

Generally, drugs that inhibit the cell wall are low toxicity drugs. What drug is an exception?

Bacitracin. It is extremely nephrotoxic so it is only used topically.

18

What are some B - lactam antibiotics?

Penicillins, Cephalosporins, Carbapenems and Monobactams, B - lactamase inhibitors.

19

T/F: Drugs that inhibit cell wall synthesis require actively dividing bacteria and can be antagonized by antibiotics that inhibit protein synthesis.

True

20

What is one category of drug that can be used to cause disruption of cell membranes?

Polymyxins

21

Drugs that cause disruption of cell membranes are toxic, do not depend on bacterial replication and are rapidly _____ drugs.

Bactericidal

22

T/F: Drugs that are used to inhibit protein synthesis all have the same level of toxicity.

False. Toxicity varies between drugs.

23

Drugs that inhibit protein synthesis depend on __________ and are mainly bacteriostatic.

Bacterial replication

24

What are some classes of drugs that inhibit protein synthesis as their MOA?

1. Aminoglycosides
2. Tetracyclines
3. Amphenicols
4. Macrolides/Lincosamides

25

What are some classes of drugs that inhibit protein synthesis as their MOA?

1. Sulfonamides
2. Fluoroquinolones
3. Nitrofurans
4. Nitromidazoles
5. Rifampin
6. Novobiocin

26

Drugs that are inhibitors of DNA synthesis and function can be ______ if they interfere with mammalian DNA.

Carcinogenic

27

What class of drug causes nephrotoxicity (renal tubular epithelial cells, collecting ducts, and more distal tubular structures)?

Aminoglycosides

28

What class of drug causes hepatotoxicity?

Tetracyclines sulfonamides

29

What classes of drugs cause a neuromuscular blockade?

Aminoglycosides, Polymyxins, and Tetracyclines

30

What class of drug causes ototoxicity?

Aminoglycosides

31

Which drugs cause GI upset?

Ampicillin and Clindamycin

32

Which drugs cause bone marrow toxicity?

Cloramphenicol and Sulfonamide

33

Which drug is known for it's hypersensitivity reactions?

Penicillins

34

What does resistance mean?

Bacterium is not inhibited or killed by concentrations of an antibiotic that would normally do so at concentrations that can be reached in the patient.

** Only use when necessary **

35

What is extrinsic resistance? (3)

1. Drug does not reach the target site.
2. Drug is inactivated
3. Target is changed

** These mechanisms can affect a single antibiotic or an entire class of drugs. **

36

What is intrinsic resistance?

Drug will never work against that class of bacteria because it does not possess the target structure (i.e. microbes with no cell wall resistant to penicillin) and does not exist in a favorable environment or antibiotic cannot get to site of action.

37

What are the two categories of acquired resistance?

1. Chromosomal mutation
2. Transferable drug resistance

38

What is chromosomal mutation?

A form of acquired resistance that potentially occurs with increased sub-therapeutic exposure (non-transferable.)

39

What is transferable drug resistance?

A form of acquired resistance where the resistant DNA is acquired from another bacterium.

40

Transferable drug resistance has three different ways to acquire resistance. What are they?

Conjugation: passed from bacteria to bacteria

Transduction: passed from virus to bacteria

Transformation: plasmids are picked up by bacteria

41

What is Biofilm?

Accumulation of microorganisms in which cells that are frequently embedded within a self-produced matrix of "slime" adhere to each other and/or a surface.

42

Which bacteria maintains a biofilm?

Pseudomonas

43

What organisms cause MRSA and MRSP in humans and dogs?

Humans: Staphylococcus aureus
Dogs: Staphylococcus pseudointermedius

44

T/F: Staph pseudointermedius is a big risk to healthy humans.

False. It only affects humans that are immunocompromised.

45

What does decolonization mean?

Treating non-clinical carries of a bacteria with antibiotics.

46

What species can you treat and recover from a bacteria without using decolonization?

Dogs