antimetabolites Flashcards Preview

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Flashcards in antimetabolites Deck (9):
1

agents

trimethoprim-sulfamethoxazole (bactrim)

2

mechanism

sulfa: interferes with bacterial folic acid metabolism via inhibition of DHFA reduction from PABA
trimetho: inhibits DHFA reduction resulting in sequential inhibition of enzymes of the folic acid path

3

resistance

lower affinity of dihydropteroate sythesis for sulfonamides. decreased bacterial permeability or active efflux, alternative metabolic path for synthesis, increased production essential metabolite.

4

spectrum

positive: MRSA/MSSA, s. pneumoniae, listeria. negative: enterobacter (ecoli, klebsiella, enterobacter), stenotrophomonas (DOC). toxo, nocardia, pneumocystis,

5

does this work on anaerobes

no

6

clinical

pneumocystis jirovecii, toxo encephalitis, UTI, listeria meningitis, MRSA.

7

adverse

rash (SJS, TEN), bone marrow suppression, renal (pseudofailure, AIN, hyperkalemia)

8

what is unique about trimeth-sulfa with the kidney

it acts as a K+ sparing diuretic.

9

interactions

inhibition of CYP2C9 affects warfarin leading to increase in the INR