Antimicrobials

Question 1

Name the 6 major classes of antibiotics

Answer 1

B-lactams (penicillins and cephalosporins)
Phenicols
Macrolides
Tetracyclines
Sulfas
Fluoroquinolones

Question 2

Time dependent antibiotics require levels above MIC for more than _____% of the dosing interval

Answer 2

75%

Question 3

T/F: it is imperative that concentration dependent antibiotics remain above the MIC for most of the dosing interval

Answer 3

False - time above MIC doesn’t matter for concentration dependent drugs

Levels several times the MIC can even increase the drugs effectiveness

Question 4

Name the 2 classes of cidals

Answer 4

Aminoglycosides
Fluoroquinolones

I remember this by those bugs are “dead AF”

Question 5

Which class of antibiotic can fit into both the static and cidal group?

Answer 5

Penicillins

Question 6

Spectrum of penicillin

Answer 6

Gram (+) and anaerobes

According to Currin, “it’s one of the best antimicrobials against anaerobes we have”

Question 7

What is the APPROPRIATE dose of PPG?

Answer 7

Appropriate dose: 3.5CC/100lb IM QD/BID

Labeled for 1CC/100lb (not nearly enough)

Question 8

Why do we recommend testing milk following PPG administration in dairy cows?

Answer 8

PPG MW is highly variable

Question 9

How does using 3.5CC/100lb dose of PPG change the slaughter withdrawal?

Answer 9

30 days! (Compared to the label 10d)

Question 10

What is special about ampicillin’s formulation?

Answer 10

Comes as a powder that you can add 3 different volumes of water to create varying concentrations

Question 11

What is the advantage to using ampicillin over PPG in a dairy situation?

Answer 11

Ampicillin has a shorter MW (48h); if given PPG, milk must be tested

Question 12

What generation cephalosporin is ceftiofur?

Answer 12

3rd

Question 13

T/F: Ceftiofur works well against gram (-) and some gram (+)

Answer 13

True

Question 14

Discuss the weird regulations that go along with 3rd generation cephalosporins

Answer 14

Can adjust INDICATION, but not dose, route, or duration

Question 15

Why is excenel the #1 used antimicrobial in dairy medicine?

Answer 15

NO MW <3

Question 16

Excede is the ____acting version of ceftiofur

Answer 16

Long

Question 17

What specific bacteria does Excede last 7-10d against?

Answer 17

Mannheimia haemolytica

Excede is good for respiratory disease

Question 18

Where is excede injected?

Answer 18

Base of the ear

(Used to be given in the middle 1/3 of the ear, but that’s changed)

Question 19

T/F: Florfenicol is the “idiot” antibiotic per Dr. Currin

Answer 19

True :)

Question 20

What is the best drug we have for penetrating the BBB?

Answer 20

Florfenicol

Question 21

Resflor = _______ + _______

Answer 21

Flunixin + Florfenicol

Question 22

Why is it important to give IV nuflor slowly?

Answer 22

Animal risks going down if given too quickly
Propylene glycol suspected to cause this

Question 23

T/F: daily injections of Tilmicosin (Micotil) will prolong your life by 30 years

Answer 23

FALSE - could actually kill you - how fun :’)

Can also kill piggies

Question 24

Tulathromycin, Tilmicosin, Gamithromycin and Tildipirosin are all members of which antibiotic class?

Answer 24

Macrolides

Question 25

Why shouldn’t macrolides be used in lactating dairy cows?

Answer 25

Affinity for fatty tissue and incredibly long withdrawals

Question 26

What are the most common indications for oxytetracycline?

Answer 26

Foot rot Pink eye

Question 27

Spectrum of activity of tetracyclines…

Answer 27

Gram (+) and (-)

Question 28

T/F: Macrolides are commonly used for metaphylaxis and treatment of respiratory disease.

Answer 28

True

Question 29

What antibiotic class do we use to treat for coccidia?

Answer 29

Sulfas!

Question 30

What does the FDA restriction say about the use of fluoroquinolones?

Answer 30

Can only be used according to the label

Question 31

What is the spectrum of activity of fluoroquinolones?

Answer 31

Gram (-)

Question 32

T/F: Macrolides maintain higher concentrations for longer in the plasma than they do the lungs.

Answer 32

False - Macrolides love the lungs

Question 33

T/F: The route of administration of oxytetracycline has minimal effect on pharmacokinetics.

Answer 33

False - Oxytetracycline given IV reaches higher serum levels than IM. IM/SQ can be used when treating things like foot rot, but if you’re dealing with a toxic mastitis, should be giving IV.