Lecture 4 9/20/23

Question 1

What is pharmacodynamics?

Answer 1

effect of the drug on the body, including mechanisms of action and efficacy

Question 2

What is pharmokinetics?

Answer 2

fate of the drug in the body

Question 3

What is the post-antibiotic effect?

Answer 3

the suppression of bacterial growth that persists after treatment

Question 4

How do time-dependent vs concentration-dependent antibiotics differ?

Answer 4

-time-dependent antibiotics have a short post-antibiotic effect and must by given more frequently regardless of dose
-concentration-dependent antibiotics have a longer post-antibiotic effect, and higher concentrations can be effective for longer periods of time

Question 5

Which antibiotics are classified as beta lactams?

Answer 5

-penicillin
-ampicillin
-cephalosporins
-sublactams
-carbapenems
-monobactams

Question 6

What is the mechanism of action for beta lactams?

Answer 6

inhibition of cell wall synthesis

Question 7

What is the spectrum of activity for beta lactams?

Answer 7

different spectrum for each antibiotic

Question 8

What is the type of antibacterial activity for beta lactams?

Answer 8

bactericidal

Question 9

What are the potential adverse effects of beta lactams?

Answer 9

-penicillin allergy/anaphylaxis
-time-dependent killing

Question 10

What antibiotics are classified as tetracyclines?

Answer 10

-oxytetracycline
-doxycycline
-minocycline

Question 11

What is the mechanism of action for tetracyclines?

Answer 11

inhibition of protein synthesis

Question 12

What is the spectrum of tetracyclines?

Answer 12

broad spectrum

Question 13

What is the type of antibacterial activity for tetracyclines?

Answer 13

bacteriostatic

Question 14

What are the potential adverse effects of tetracyclines?

Answer 14

-irritant
-cardiovascular effects
-tooth discolaration
-intestinal flora alteration
-nephrotoxicity

Question 15

What other critical information exists for tetracyclines?

Answer 15

-time dependent
-chelating agents
-cross placental barrier
-secreted in milk
-anti-inflammatory
-neuro-protective
-immunomodulant

Question 16

What antibiotics are classified as aminoglycosides?

Answer 16

-gentamicin
-amikacin
-tobramycin

Question 17

What is the mechanism of action for aminoglycosides?

Answer 17

inhibition of protein synthesis

Question 18

What is the spectrum of activity for aminoglycosides?

Answer 18

broad spectrum

Question 19

What is the type of antibacterial activity for aminoglycosides?

Answer 19

bactericidal

Question 20

What are the potential adverse effects of aminoglycosides?

Answer 20

-nephrotoxicity
-ototoxicity
-cranial nerve VII toxicity
-vestibular/cochlear damage

Question 21

What other critical information exists for aminoglycosides?

Answer 21

-concentration dependent
-oxygen dependent
-prolonged post-antibiotic effect
-needs parenteral admin.
-does not penetrate blood brain barrier
-synergism w/ beta lactams, but physically incompatible

Question 22

What antibiotics are classified as fluoroquinolones?

Answer 22

-enrofloxacin
-ciprofloxacin

Question 23

What is the mechanism of action for fluoroquinolones?

Answer 23

inhibition of DNA gyrase

Question 24

What is the spectrum of activity for fluoroquinolones?

Answer 24

broad spectrum

Question 25

What is the type of antibacterial activity for fluoroquinolones?

Answer 25

bactericidal

Question 26

What are the potential adverse effects of fluoroquinolones?

Answer 26

-arthropathy -ocular toxicity

Question 27

What other critical information exists for fluoroquinolones?

Answer 27

-synthetic -concentration dependent -high intracellular conc. in phagocytes -prolonged post-antibiotic effect -rapid resistance development

Question 28

What antibiotics are classified as macrolides?

Answer 28

-erythromycin -azithromycin -clarithromycin

Question 29

What is the mechanism of action for macrolides?

Answer 29

inhibition of protein synthesis

Question 30

What is the spectrum of activity for macrolides?

Answer 30

broad spectrum

Question 31

What is the type of antibacterial activity for macrolides?

Answer 31

bacteriostatic

Question 32

What are the potential adverse effects of macrolides?

Answer 32

GI effects

Question 33

What other critical information exists for macrolides?

Answer 33

-intracellular accumulation in phagocytes -effective against intracellular bact. -immunomodulary effect

Question 34

What antibiotics are classified as sulfa drugs?

Answer 34

-sulphonamide -sulfamethoxazole -sulfadiazine

Question 35

What is the mechanism of action for sulfa drugs?

Answer 35

inhibition of folic acid synthesis, preventing the nucleic acid synthesis pathway

Question 36

What is the spectrum of activity for sulfa drugs?

Answer 36

broad spectrum

Question 37

What is the type of antibacterial activity for sulfa drugs?

Answer 37

bacteriostatic

Question 38

What are the potential adverse effects of sulfa drugs?

Answer 38

-allergic reactions -keratoconjunctivitis

Question 39

What other critical information exists for sulfa drugs?

Answer 39

synergistic with diaminopyrimidines

Question 40

What are the reasons for bacterial culture and antimicrobial susceptibility testing?

Answer 40

-confirm presence of bact. infection -identify responsible pathogen -choose most effective antibiotic -improve recovery chances/speed -lower complications -reduce resistance -reduce expenses

Question 41

What are important points to consider regarding resistance?

Answer 41

-bact. may be intrinsically resistant -knowledge of resistance can help avoid inappropriate/ineffective therapies

Question 42

What is the antimicrobial susceptibility test?

Answer 42

test to determine whether bacteria are susceptible to a particular antimicrobial agent

Question 43

What are the two types of AST?

Answer 43

-broth/agar dilution -disk diffusion

Question 44

How are bacteria determined to be susceptible via the disk diffusion test?

Answer 44

greater zone of inhibition diameter indicates greater susceptibility

Question 45

How are bacteria determined to be susceptible via the broth dilution test?

Answer 45

the lower the minimum inhibitory concentration, the greater the susceptibility

Question 46

What is the minimum inhibitory conc.?

Answer 46

the minimum amount of drug required to inhibit bact. growth

Question 47

What is the E-Test-Gradient diffusion test?

Answer 47

test that uses both diffusion and dilution to measure an exact MIC

Question 48

Why can it be beneficial to use antimicrobial combinations?

Answer 48

-obtain antimicrobial synergism -treat polymicrobial infections -decrease resistance -reduce drug toxicity

Question 49

What is four-quadrant therapy?

Answer 49

-method for treating microbial infection when pathogen is unknown and consequences of treatment failure are severe -includes antibiotics to treat gram + aerobes, gram + anaerobes, gram - aerobes, and gram - anaerobes -effective against all likely bacteria -NOT just using a broad spectrum