Phenicols

Question 1

Are phenicols lipid or water soluble?

Answer 1

Lipid soluble, so can cross BBB.

Question 2

How do phenicols work?

Answer 2

Inhibit protein synthesis at the 50S ribosomal subunit.

Question 3

Resistance to phenicols is chromosome mediated. T/F

Answer 3

FALSE! It is plasma mediated.

Question 4

Are phenicols bactericidal or bacteriostatic?

Answer 4

Bacteriostatic.

Question 5

What do phenicols work on?

Answer 5

ALL broad spec, including anaerobes.
Special spec: B. fragilis, Rickettsia, Mycoplasma.
Can be effective against enterococcal infections

Question 6

Chloramphenicol:

Answer 6

Approved in the dog as tablet or capsule, sometimes human IV product used.

Question 7

Florfenicol:

Answer 7

Feed additive (VFD). One of the few drugs approved in fish.

Question 8

How are phenicols absorbed?

Answer 8

Oral: Chloramphenicol is well absorbed orally in all non ruminants.
Parenteral: Chloramphenicol is well tolerated when used IV. Bioavailability is lower than oral product.

Question 9

How are phenicols eliminated?

Answer 9

Hepatic

Question 10

Adverse rxns to phenicols:

Answer 10

Not well tolerated in cats –> anorexia/depression.
Drug interactions.
Chloramphenicol can be used in horses, NOT florfenicol.
Peripheral neuropathy.
Fatal aplastic anemia caused by chloramphenicol.
Chloramphenicol is BANNED from all food animal use!