Macrolides

Question 1

Are macrolides static or cidal

Answer 1

Static

Question 2

List the macrolides

Answer 2

ACE-TTTT

Azithromycin
Clarithromycin
Erythromycin

Tiamulin
Tilmicosin
Tulathromycin
Tylosin

Question 3

MOA macrolides

Answer 3

Reversibly binds to 50s subunit

Inhibits of translocation of tRNA from aminoacid acceptor site

Interferes with addition of new peptide bond

Question 4

Which macrolide is the ‘parent molecule’ from which others are synthesized

Answer 4

Erythromycin

Question 5

Which Macrolide is used in cattle and swine for resp diseases

Answer 5

Tulathromycin (long half life - SC)

Question 6

Do macrolides interfere with mammalian mitochondrial protein synthesis

Answer 6

No

Question 7

At which pH do macrolides have increased action

Answer 7

pH 8

Question 8

Are macrolides useful for abscesses, necrotic tissue or acidic urine

Answer 8

No - they function at basic pHs

Question 9

Which class of drugs do macrolides have antagonistic effects with

Answer 9

Chloramphenicols - compete for binding site

Question 10

Which drug is given with rifampin to treat Rhodoccus equi in foals (pneumonia)

Answer 10

Erythromycin

Question 11

Which drug is given to treat C. jejuni in dogs and cats

Answer 11

Erythromycin

Question 12

Which drug has expanded spectrum and is useful for mycoplasma

Answer 12

Tilmicosin

Question 13

Which drug is used for respiratory pathogens, such Actinobacillus, in cows and pigs

Answer 13

Tilmicosin

Question 14

Which drug is more potent against mycoplasma

Answer 14

Tylosin

Question 15

Which drug is used for pink-eye

Answer 15

Tylosin

Question 16

Which drug is used for swine dysentery

Answer 16

Tylosin

Question 17

Which drug is used for pleuropneumonia

Answer 17

Tylosin

Question 18

Which drug is used for colitis in dogs

Answer 18

Tylosin

Question 19

Which drug is given as a feed additive

Answer 19

Tylosin

Question 20

Which drugs have a long half life

Answer 20

Azithromycin

Tulathromycin

Question 21

Which drug can treat Rhodoccus equi in foals

Answer 21

Clarithromycin

Question 22

What is preferred route of admin for macrolides?

Answer 22

Oral (parenteral is irritating and painful)

Question 23

Distribution of macrolides

Answer 23

Wide - high lipid solubility, high concentration in lungs

Question 24

Which drugs have post-antibiotic effect

Answer 24

Azithromycin
Tulathromycin

(long half life)

Question 25

Which macrolide has most metabolism? Where

Answer 25

Erythromycin - oxidation in liver

Question 26

Excretion of erythromycin

Answer 26

Bile
Urine
Milk

Question 27

Excretion of Azithromycin and Tylosin

Answer 27

Bile

Question 28

Excretion of clarithromycin and tilmicosin

Answer 28

Bile

Urine

Question 29

T/F macrolides are toxic

Answer 29

False

Question 30

Adverse effects of erythromycin in dogs

Answer 30

Regurgitation/vomiting

Question 31

Which macrolide is fatal to horses ***

Answer 31

Tylosin

Question 32

Adverse effects of macrolides

Answer 32

Severe diarrhea (calves)

Self-limiting diarrhea foals
Severe diarrhea - adult horses

Cardiotoxicity

Question 33

IV administration of tilmcosin has what effect

Answer 33

Negative inotropic

Question 34

Efficacy predictor of macrolides? Any exceptions

Answer 34

Type II (time dependent killing)

Yes - tulathromycin and azithromycin are type III

Question 35

Efficacy predictor of tulathromycin and azithromycin

Answer 35

Type III (time dependent killing with persistent effects)