Nitrofurantoin Flashcards
Nitrofurantoin is a
nitrated heterocyclic compound
Nitrofurantoin is FDA approved for
cysitis
Originally nitrofurantoin was developed as _____ but was poorly _____
a microcrystalline product; tolerated (diarrhea, nausea)
Primary product (Nitrofurantoin)
macrocrystalline (Macrobid)
How does Macrobid differ from the microcrystalline version?
delayed absorption with improved tolerability
Nitrofurantoin MOA
activated by bacterial flavoproteins to reactive intermediates
How do activated intermediates damage bacteria?
damage ribosomal proteins, DNA, and other macromolecules involved in metabolism and cell wall synthesis
How is nitrofurantoin selective for bacterial cells?
bacteria reduce it more rapidly than mammalian cells
Nitrofurantoin oral absorption
90%; good
Nitrofurantoin 1/2 life
short
Nitrofurantoin elimination
40% unchanged in urine
Nitrofurantoin urine elimination take place
in glomerular filtration, tubular secretion, and tubular reabsorption
Alkalinized urine may ___ antimicrobial activity
reduce
Clinical response is dependent on ____ therefore, impaired renal function ___ the utility of nitrofurantoin
urine concentrations; limits
Nitrofurantoin tissue penetration
does not penetrate well into tissues, including kidney parenchyma, CSF, eye, prostate, or abiotic fluid
Nitrofurantoin should/should not be taken with food
should to improve tolerability and enhance absorption
Nitrofurantoin ___ renal adjustment
needs
Nitrofurantoin is contraindicated in people with
CrCl < 60 ml/min
Emerging data suggests that nitrofurantoin is safe and effective if used for short duration in patients with
CrCl 30-60 ml/min
Decision to use Nitrofurantoin in patients with CrCl 30-60ml/min will depend on
alternative regimen, duration of treatment, and physical f/u
Nitrofurantoin spectrum coverage
dark purple: MSSA, MRSA, E. faecium, E. faecalis
dark red: E. coli, citrobacter
light red: klebsiella, enterobacter, p. aeruginosa
Nitrofurantoin adverse effects
GI rare neurologic, hepatotoxicity, pulmonary toxicity, fibrosis, hemolytic anemia in patients with G6PD deficiency urine discoloration (brown) false negative glucosuria test
Nitrofurantoin is contraindicated in
pregnancy >38 weeks and neonates <1 month
Nitrofurantoin drug interactions
magnesium based antacids (reduced nitro absorption), probenecid (increases nitro serum concentrations)
Nitrofurantoin indications
only indicated for cystitis since it has insufficient concentrations in tissues to treat pyelonephritis and in serum to treat anything else
Nitrofurantoin duration of therapy
5 days typically for uncomplicated
Nitrofurantoin primary adverse effects for uncomplicated disease
GI
