Flashcards in L30 - Drugs Deck (28)
Name the 2 drugs that block folate synthesis
What enzyme do sulfonamides target?
We don't have this enzyme so no side-effects to humans in taking this
What enzymes does trimethoprim target?
Drug has MUCH higher affinity for the bacterial version of this enzyme - small side effects for humans
Sulfonamides are rarely used alone. What are they given with? Why?
Trimethoprim + sulfamethoxazole (TMP-SMX)
- Enhanced activity via synergy
- Broad spectrum bactericidal action
- Less resistance
S. aureus (g+)
Some protozoa & fungi
Pseudo & enterococci resistant
* Urinary, respiratory, GI infections*
How are folate antagonists given
What are the adverse effects for folate antagonists
Rash, GI = common
- Toxic epidermal necrolysis
- Amenias and thrombocytopenia
What can happen with TMP-SMX during pregnancy?
Kernicterus = high bilirubin
Brain dysfxn in the baby
Plasmid w/ dhfr gene
Transposon (Tn7) of integrons
Plasmid that made TMP resistance/changes coding of dihydropteroate synthetase
What are the 3 DNA inhibitors
Double strand breaks to stabalizes topo-DNA complex
No DNA replication or RNA transcription
Chromosome fragmentation --> bactericidal (!)
What are quinolones used against
Gram - by inhibiting topo2
Gram + by inhibiting topo4
Atypicals & mycobacteria
How are quinolones given?
BUT poor absorption w/ divalent cations
Drug primarily targets topo2 and has good [ ] in urine. Not gets vs Step
Drug primarily targets topo4 and good vs Step
Quniolone that has strong g + and anaerobic activity
What causes fluroquinolone resistance
gyrA or parC mutations
Quinolone adverse effects
What quinolone are you using to treat UTIs
Good against gram-/+ uropathogens
PO - poor serum but good urine [ ]
Might see nausea & pulm fibrosis
What are the 2 RNA inhibitors?
Binds B subunit of RNA polymerase
Rifamycin metabolism. What are the 3 forms of rifamycin?
Cp450 3A4 metabolism
Rifampin - induces this enzymes
Rifaximin - not absorbed so for GI infections
Prophylasis of N.meningitidis & S.aureus
GI as rifaximin - traveler's diarrhea
Rifamycin adverse effect
No open DNA complex --> X RNA polymerase