Nitrofurantoin Flashcards
What part of a bacterial cell does nitrofurantoin target?
DNA
How does nitrofurantoin work?
Bacterial cells have nitrofurantoin reductase.
Nitrofuran reductase metabolises (reduces) nitrofuranotin –> an active DNA damaging metabolite
This active DNA damaging metabolite causes cell death making it BACTERIOCIDAL
Is nitrofurantoin bacteriostatic or bactericidal?
Batceriocidal
What bacteria does nitrofurantoin work against?
Gram positive (Staphylococuss saprophytious) and Gran negative (e.coli) These are common causes of UTI
How do bacteria become resistant to nitrofurantoin?
Some bacteria have reduced levels of nitrofuran reductase - RARE IN ECOLI
Some bacteria have intrinsic resistance e.g. kelbsiella and proteus - these are less common causes of UTI
What bacteria have intrinsic resistance to nitrofurantoin?
Kelbsiella and proteus
What are the common uses of nitrofurantoin?
- UTI
- first line for UTI (trimethoprim and amoxicillin otherwise)
What makes nitrofurantoin good for use against UTIs?
Good as bactericidal
Had most bactericidal effect in acidic environments e.g. UTI
Reaches high concentrations in urine
What are the contra-indications for using nitrofurantoin?
- Pregnant
- Babies in first three months
- Renal Impairment (impaired excretion increases toxicity and reduces efficacy)
What are the cautions when using nitrofurantoin?
Long term prevention of UTI
- chronic use increases risk of adverse effects especially in the elderly
What are the interactions with nitrofurantoin?
No significant interactions
What are the common side effects of nitrofurantoin?
- GI Upset (nausea and diarrhoea)
- Hypersensitivity reactions (immediate and delayed)
- Turns urine dark yellow/brown
- Less commonly
- Chronic pulmonary reactions (pneumonitis fibrosis)
- Hepatits
- Peripheral neuropathy
- In neonates: haemolytic anemia (ask immature RBCS cant mop up nitrofurantoin superoxides)
What form is nitrofurantoin available in?
Oral administrations
How long should nitrofurantoin be prescribed for?
3 days in women with uncomplicated UTI
7 day course in men or more complicated
Should you use nitrofurantoin for pyelonephritis?
No
Use co-amoxiclav with gentamicin
Or ciprafloxacin