ID I: SULFONAMIDES Flashcards
What does sulfamethoxazole (SMX) inhibit?
dihydrofolic acid formation from para aminobenzoic acid, interferes with bacterial folic acids synthesis
What does trimethoprim (TMP) inhibit?
dihydrofolic acid reduction to tetrahydrofolate, resulting in inhibition of the folic acid pathway
Bactrim coverage
staphylococci (MRSA, CA-MRSA)
S Pneumoniae
BROAD gram-negative
What gram negatives does Bactrim cover?
haemophilus, proteus, e coli, klebsiella, enterobacter
shigella, salmonella, stenotrophonomas
What opportunistic pathogens does Bactrim cover?
opportunistic pathogens: Nocardia, pneumocystis, toxoplasmosis
What does Bactrim NOT cover?
pseudomonas
enterococci
atypicals
anaerobes
The dose of bacteria is based on what component?
TMP (5:1)
What is the dose for uncomplicated UTI?
1 DS tablet PO BID x 3 days
What is the dose for pneumocystis pneumoniae prophylcaxis (PCP)?
1 DS or SS tablet DAILY
Double strength
800mg SMX/ 160mg TMP
400/80
Contraindiations?
sulfa allergy
Warnings for Bactrim
skin reactions: SJS/TEN, TTP
G6PD deficiency – hemolysis!
What are the side effects of Bactrim?
photosensitivity
increase K
hemolytic anemia (+ Coombs test)
crystalluria (8oz water)
Bactrim is a moderate inhibitor of 2c9, which means..
INC INR!!!!!!!
*use alt abx if available
2c9 inducers can ..
dec levels of Bactrim
leucovorin
