Anti-bacterials Flashcards
True of the MOA of aminoglycosides
a. Used synergystically with B lactams
b. Irreversibly binds to 30s ribosome and inhibit protein synthesis
c. Reversibly binds to 30s ribosome and inhibit protein synthesis
d. Irreversibly binds to 50s ribosome
C; Tetracyclines bind reversibly to 30s ribosome
Most ototoxic agents EXCEPT
a. neomycin
b. kanamycin
c. amikacin
d. tobramycin
e. AOTA
D;
Most nephrotoxic agents EXCEPT
a. Neomycin
b. Tobramycin
c. Amikacin
d. Gentamycin
e. AOTA
C.
True of Gentamycin’s spectrum of activity
a. has activity against S. aureus, S. viridans
b. has activity against anaerobes
c. has activity against E. coli, Klebsiella, Proteus,
Enterobacter, Acitenobacter
d. has activity against P. aeruginosa
B.
Ototoxic effects of gentamicin will manifest as _________, __________
tinnitus, verstibular damage
Enumerate 3 ways of tetra/doxy/minocycline resistance
- Impaired influx/increased effllux via Tet(AE) in Gram -
- Ribosome protection by Gram +
- Enzyme inactivation
Tetracycline GI absorption is impaired by the following EXCEPT
a. food (except doxy/minocycline)
b. divalent cations
c. alkaline pH
d. acids
D
True of pharmacokinetics of tetracyclines EXCEPT
a. Penetrates BBB
b. Penetrates placenta
c. Should not be orally administered with milk, antacids, or ferrous sulfate
d. AOTA
A
Clinical uses of tetracyclines EXCEPT
a. Infections caused by rickettsiae
b. M. pneumonia infections
c. in combination regimens for H. pylori gastric ulcer
d. Gonorrhea
D; other uses: treatment of acne, exacerbations of bronchitis, community-acquired pneumonia, Lyme disease, relapsing fever, leptospirosis, nontuberculous mycobacterial infections
Antibacteria that binds to 50s subunit of the bacterial ribosome and inhibits peptide bond formation
Chloramphenicol
Resistance to Chloramphenicol is due to
chloramphenicol acetyltransferase
True of chloramphenicol pharmacokinetics EXCEPT
a. adjusted for renal failure but not for hepatic failure
b. widely distributed to all tissues and body fluids: CNS, placenta
c. Oral formulation yields higher blood concentrations
d. NOTA
A; must be adjusted for hepatic failure not renal failure
Antibacterial that binds to 50s subunit of the ribosomal RNA and prevents peptide chain elongation by blocking the polypeptide exit tunnel
Macrolides
What chemical structure relates macrolides together?
Macrocyclic lactone ring
Resistance of Macrolides are due to the ff. (give 3)
- reduced permeability of the cell membrane or active efflux
- Production of esterases that hydrolyze macrolides
- Modification of ribosomal binding site