Nitrofurantoin

Question 1

Nitrofurantoin is a

Answer 1

nitrated heterocyclic compound

Question 2

Nitrofurantoin is FDA approved for

Answer 2

cysitis

Question 3

Originally nitrofurantoin was developed as _____ but was poorly _____

Answer 3

a microcrystalline product; tolerated (diarrhea, nausea)

Question 4

Primary product (Nitrofurantoin)

Answer 4

macrocrystalline (Macrobid)

Question 5

How does Macrobid differ from the microcrystalline version?

Answer 5

delayed absorption with improved tolerability

Question 6

Nitrofurantoin MOA

Answer 6

activated by bacterial flavoproteins to reactive intermediates

Question 7

How do activated intermediates damage bacteria?

Answer 7

damage ribosomal proteins, DNA, and other macromolecules involved in metabolism and cell wall synthesis

Question 8

How is nitrofurantoin selective for bacterial cells?

Answer 8

bacteria reduce it more rapidly than mammalian cells

Question 9

Nitrofurantoin oral absorption

Answer 9

90%; good

Question 10

Nitrofurantoin 1/2 life

Answer 10

short

Question 11

Nitrofurantoin elimination

Answer 11

40% unchanged in urine

Question 12

Nitrofurantoin urine elimination take place

Answer 12

in glomerular filtration, tubular secretion, and tubular reabsorption

Question 13

Alkalinized urine may ___ antimicrobial activity

Answer 13

reduce

Question 14

Clinical response is dependent on ____ therefore, impaired renal function ___ the utility of nitrofurantoin

Answer 14

urine concentrations; limits

Question 15

Nitrofurantoin tissue penetration

Answer 15

does not penetrate well into tissues, including kidney parenchyma, CSF, eye, prostate, or abiotic fluid

Question 16

Nitrofurantoin should/should not be taken with food

Answer 16

should to improve tolerability and enhance absorption

Question 17

Nitrofurantoin ___ renal adjustment

Answer 17

needs

Question 18

Nitrofurantoin is contraindicated in people with

Answer 18

CrCl < 60 ml/min

Question 19

Emerging data suggests that nitrofurantoin is safe and effective if used for short duration in patients with

Answer 19

CrCl 30-60 ml/min

Question 20

Decision to use Nitrofurantoin in patients with CrCl 30-60ml/min will depend on

Answer 20

alternative regimen, duration of treatment, and physical f/u

Question 21

Nitrofurantoin spectrum coverage

Answer 21

dark purple: MSSA, MRSA, E. faecium, E. faecalis

dark red: E. coli, citrobacter

light red: klebsiella, enterobacter, p. aeruginosa

Question 22

Nitrofurantoin adverse effects

Answer 22

GI
rare neurologic, hepatotoxicity, pulmonary toxicity, fibrosis, hemolytic anemia in patients with G6PD deficiency
urine discoloration (brown)
false negative glucosuria test

Question 23

Nitrofurantoin is contraindicated in

Answer 23

pregnancy >38 weeks and neonates <1 month

Question 24

Nitrofurantoin drug interactions

Answer 24

magnesium based antacids (reduced nitro absorption), probenecid (increases nitro serum concentrations)

Question 25

Nitrofurantoin indications

Answer 25

only indicated for cystitis since it has insufficient concentrations in tissues to treat pyelonephritis and in serum to treat anything else

Question 26

Nitrofurantoin duration of therapy

Answer 26

5 days typically for uncomplicated

Question 27

Nitrofurantoin primary adverse effects for uncomplicated disease

Answer 27

GI