Antimicrobial Medications

Question 1

Use of a drug to prevent imminent infection of a person at risk.

Answer 1

Prophylaxis

Question 2

what did Alexander Flemming identify mold as?

Answer 2

Penicillium

Question 3

Substances produced by natural metabolic processes of some microorganisms that can destroy other microorganisms

Answer 3

Antibiotics

Question 4

what is the primary goal of antimicrobial
chemotherapy?

Answer 4

administer drug to infected person, destroying the infective agent without harming host’s cells

Question 5

Features of Antimicrobial Drugs

1. Drugs differ in how they are what?
   -Important factor for consideration when prescribing
2. The rate of elimination of drug from body is expressed in?
   – Time it takes for the body to eliminate one half the original dose in serum
   – dictates frequency of dosage
3. T or F: Patients with liver or kidney damage tend to excrete drugs more quickly?

Answer 5

1. distributed, metabolized and excreted
2. half-life
3. False, they excrete drugs more slowly

Question 6

If antimicrobials are effective against a LIMITED array of microbial types this is known as what?

Is this effective against gram + or -?

Answer 6

Narrow spectrum

can be effective against gram + OR - not both

Question 7

Antimicrobials effective against a wide variety of microbial types

Is this effective against gram + or -?

Answer 7

broad spectrum

can be affective against BOTH gram+ and -

Question 8

Who successfully purified penicillin?

What were they awarded with?

Answer 8

Ernst Chain and Howard Florey

Noble prize in Physiology in medicine with Fleming (1945)

Question 9

Where do most modern antibiotics come from?

Answer 9

organisms living in the soil (bacterial species & fungi)

Question 10

When drugs are chemically altered to impart new characteristics what is this termed?

Answer 10

semi-synthetic drugs

Question 11

Antibiotics are classified by their what?

Answer 11

Mechanism of action

Question 12

What are 4 adverse effects of antimicrobial drugs?

Answer 12

1. Allergic reactions (penicilin)
2. Toxic effects (aplastic anemia)
3. Suppression of normal flora (colitis)
4. antimicrobial resistance

Question 13

Antimicrobials that interfere
with the synthesis of cell wall
do not interfere with eukaryotic
cell. Why is this?

Answer 13

Animal cells lack a cell wall and plant cell do not.

Question 14

1. Why is Gram (-) resistant to Vancomycin?
2. _____________
   – Interferes with transport of PTG precursors across cytoplasmic membrane
   – Toxicity limits use to topical applications
   – Common ingredient in non-prescription first-aid ointments

Answer 14

1. Does not cross lipid membrane of Gram (-)
2. Bacitracin

Question 15

Define high therapeutic index and give 3 examples

Answer 15

low toxicity with high effectiveness

1. β lactam drugs
2. Vancomycin
3. Bacitracin

Question 16

1. _________________
   * e.g. Gentamicin,
   streptomycin
   * Side effects with extended use include Nephrotoxicity
2. ________________
   * Effective against certain Gram (+) and Gram (-)
   - nephrotoxicity & teeth discoloration
   * e.g. doxycycline has longer
   half-life
   –Allows for less frequent dosing

Answer 16

1. Aminoglycosides
2. Tetracyclines

Question 17

What do Penicillins and Cephalosporins inhibit?

Answer 17

function of enzymes that help form peptide bridge
between glycan molecules

Question 18

T/F Some microbes are resistant to drugs through production of β-lactamase enzyme

Answer 18

TRUE

Question 19

Newer group, broad spectrum

Currently account for a majority of all antibiotics administered

These are resistant to most β
lactamases/penicillinases

these are charteristics of?

Answer 19

Cephalosporins

Question 20

What 4 drugs are responsible for inhibiting protein synthesis?

Answer 20

1. Aminoglycosides
2. Tetracyclins
3. Macrolids
4. Chloramphenicol

Question 21

1. Two antibacterial drugs that inhibit
   nucleic acid synthesis?
2. Two types of Fluoroquinolones
3. Rifamycins can be used against what?

Answer 21

1. Fluoroquinolones and Rifamycins
2. Ciprofloxacin and Moxifloxacin
3. Mycobacterium

Question 22

3 types of macrolids?

Answer 22

1.erythromycin
2. clarithromycin
3. azithromycin

Question 23

Which drug is generally used as drug of last resort for life
threatening infections?

Answer 23

Chloramphenicol

Question 24

What is a lethal side effect of Chloramphenicol?

Answer 24

aplastic anemia

Question 25

1. Antibacterial Drug that alters the cell membrane? 2. Polymyxin B Binds membrane of Gram (-) or (+) cells? 3. Polymyxin B Limits use to what and why?

Answer 25

1. Polymyxin B 2. Binds membrane of Gram (-) cells 3. topical application since it can also bind to Eukaryotic cells

Question 26

T/F Humans can make their own folic acid

Answer 26

FALSE, they CANNOT make their own folic acid, it must come from the diet

Question 27

Why is susceptibility only tested with pure cultures and not mixed cultures?

Answer 27

Because you cannot tell in a mixed culture if it is the pathogen or contaminant causing infection

Question 28

1. the smallest amount of an agent needed to inhibit growth of a microorganism? 2. What technique is used for MIC?

Answer 28

1. minimum inhibitory concentration (MIC) 2. Tube Dilution

Question 29

In a Kirby-Bauer Disc Diffusion Test, the inoculum density is standardized using what standard?

Answer 29

McFarland Standard

Question 30

The Kirby-Bauer Disc Diffusion Test is used for what?

Answer 30

to qualitatively determine susceptibility

Question 31

1. An adaptive response in which microorganisms begin to tolerate an amount of drug that would ordinarily be inhibitory? 2. Microbes become newly resistant to a drug after either? (2 things)

Answer 31

1. Drug resistance 2. Spontaneous mutations or Acquisition of new genes via plasmids

Question 32

What represents susceptibility in Kirby-Bauer Disc Diffusion Test

Answer 32

Clear zone of inhibition around disc

Question 33

T/F The E test uses strips impregnated with gradient concentration of antibiotic -From highest concentration to lowest

Answer 33

TRUE

Question 34

Every time you take a drug what happens in your system?

Answer 34

Drug resistance begins to develop and can dominate the population.

Question 35

Give 3 bacteria examples of emerging antimicrobial resistance

Answer 35

1. Staphylococcus aureus 2. Mycobacterium tuberculosis 3. Enterococci

Question 36

fill in the blank w/ emerging antimicrobial resistance ____________: common causes of nosocomial infections ____________: Part of normal intestinal flora _____________: Organism is acid-fast,

Answer 36

1. Staphylococcus aureus & Enterococci 2. Enterococci 3. Mycobacterium tuberculosis

Question 37

Polyenes and Azoles are drugs that do what?

Answer 37

target ergosterol

Question 38

A fungal infection is caused by a ______________, it is very hard to kill these organisms and not harm your cells

Answer 38

eukaryote

Question 39

Failure of antimicrobial treatment could be due to what 3 things?

Answer 39

inability of the drug to diffuse resistant cells in the culture infection caused by more than one pathogen

Question 39

T/F Antimicrobials can alter your normal flora If so, explain why?

Answer 39

TRUE broad-spectrum antimicrobial will destroy infectious agents but also beneficial species

Question 40

Bacteriophage therapy

Answer 40

New way of treating superbug infections