Phenicols

Question 1

what are the physicochemical properties of phenicols?

Answer 1

very lipid soluble with high volumes of distribution

Question 2

what is the distribution of phenicols?

Answer 2

penetrate intracellularly and widely distributed

Question 3

do phenicols cross the blood brain barrier?

Answer 3

yes

Question 4

how are phenicols metabolized?

Answer 4

majority hepatic metabolism
P450 enzyme inhibitor

Question 5

what is the mechanism of action of phenicols?

Answer 5

inhibition of protein synthesis at the 50S ribosomal subunit
mostly bacteriostatic

Question 6

what is the efficacy of phenicols dependent on?

Answer 6

time above MIC
for as much of interval as possible

Question 7

who is chloramphenicol used in?

Answer 7

dogs: tablet or capsule
horses commonly

Question 8

who is florfenicol used in?

Answer 8

beef cattle

Question 9

what drug can be effective against enterococcal infections?

Answer 9

chlorampheenicol

Question 10

what is an adverse effect of chloramphenicol in primates (including humans)?

Answer 10

fatal aplastic anemia

Question 11

does fatal aplastic anemia occur with florfenicol?

Answer 11

no

Question 12

how common is fatal aplastic anemia in primates?

Answer 12

1 in every 25,000 to 60,000 patients

Question 13

what can florfenicol cause in horses?

Answer 13

severe diarrhea and colitis

Question 14

what can long-term use of phenicols lead to?

Answer 14

bone marrow suppression
reversible upon discontinuation of the drug

Question 15

why are phenicols prone to drug interactions?

Answer 15

inhibition of P450 enzyme system

Question 16

who should we be cautious in using phenicols in?

Answer 16

cats
pregnancy
neonates except foals: excreted well into milk as well

Question 17

is chloramphenicol banned in all food animal use?

Answer 17

yes

Question 18

do phenicols cross the blood brain barrier?

Answer 18

yes

Question 19

do phenicols concentrate well in urine (parent drug)?

Answer 19

not well enough for UTIs

Question 20

what is florfenicol used in beef cattle for?

Answer 20

repository
bovine respiratory disease and foot rot

Question 21

what is the four quadrant coverage of chloramphenicol?

Answer 21

E. coli: +
Staphylococcus: +
Steptococcus: +
anaerobe: +

Question 22

outside of the four quadrants, what does chloramphenicol/phenicols work against?

Answer 22

B. fragilis: +
Chlamydia: +/-
Mycoplasma: +
Rickettsia: +

Question 23

how bad is aplastic anemia caused by chloramphenicol?

Answer 23

fatal without a bone marrow transplant

Question 24

is fatal aplastic anemia from chloramphenicol dose dependent?

Answer 24

no

Question 25

can you use phenicols in horses?

Answer 25

florfenicol no
chloramphenicol yes