UTI drugs info Flashcards
dose of nitrofurantoin for lower UTI for pregnant women - MR and IR preps
& when to avoid in pregnancy
100mg BD 7 days (MR prep)
50mg QDS 7 days (IR prep)
avoid at term risk of neonatal haemolysis*
dose of nitrofurantoin for lower UTI for men - MR and IR preps
100mg BD for 7 days - MR
50mg QDS for 7 days - IR
dose of nitrofurantoin for non-pregnant women with lower UTI - MR and IR preps
50mg QDS for 3 days - IR
100mg BD for 3 days - MR
dose of nitrofurantoin for catheter associated UTIs (IR and MR)
50mg QDS 7 days (IR)
100mg BD 7 days (MR)
when would you give immediate release preps over MR preps of nitrofurantoin for UTIs
when MR preps are unavailable
nitrofurantoin dose for SEVERE CHRONIC RECURRENT UTI
100mg QDS for 7 days (using IR preps, not MR)
dose of nitrofurantoin for prophylaxis of recurrent UTI (using IR preps)
50-100mg OD, at night
alternatively 100mg for 1 dose to be taken following exposure to trigger
MHRA nitrofurantoin: pulmonary and hepatic adverse drug reactions
- increase vigilance for acute pulmonary reactions in 1st week of treatment
- closely monitor pt on long term therapy for new or worsening respiratory symptoms esp in elderly
- discontinue immediately if new or worsening symptoms of pulmonary damage
- caution when prescribing to pt with pulmonary disease which may mask signs and symptoms of adverse reactions
- be vigilant for signs and symptoms of hepatic dysfunction esp with long term therapy
- caution in pt with HI
nitrofurantoin contraindicated in this age
under 3 months
3 contraindications of nitrofurantoin
acute porphyrias
G6PD deficiency
less than 3 months
what is the interaction (not severe or anything) between nitrofurantoin and vincristine and similar drugs
amiodarone, taxanes, platins, isoniazid,
amiodarone, taxanes, platins, isoniazid, leflonamide, metronidazole, phenytoin, vinka alkaloids
increased risk of peripheral neuropathy
side effects which warrant discontinuation of nitrofurantoin (3)
- unexplained haematological or neurological syndromes (such as peripheral neuropathy) occur
- hepatitis
- pulmonary reactions (usually occur within first week of treatment and are reversible with cessation of therapy)
acute pulmonary reactions with nitrofurantoin usually occur within …
first week of treatment
can you use nitrofurantoin in BF?
avoid
only small amounts present in milk but enough to produce haemolysis in G6PD deficient infants
giving nitrofurantoin to pt with renal impairment increases risk of
peripheral neuropathy
avoid nitrofurantoin if eGFR
less than 45
monitoring requirements of nitrofurantoin
- on long term therapy, monitor LFTs and monitor for pulmonary symptoms esp in elderly (discontinue if deterioration in lung function)
patient and carer advice for nitrofurantoin - seek immediate medical attention if
signs of pulmonary, hepatic, haematological or neurological adverse reactions develop
does nitrofurantoin effect driving and skilled tasks
yes
Patients and carers should be counselled on the effects on driving and performance of skilled tasks—increased risk of dizziness and drowsiness.
do you need to take nitrofurantoin with or without food
take with or just after food or a meal
nitrofurantoin can colour urine which colour
yellow brown
use of trimethoprim in pregnancy and BF
- avoid in pregnancy, teratogenic risk in 1st trimester. folate antagonist.
- short term use in BF not known to be harmful
trimethoprim dose adjustments in RI
- caution in RI
- dose reduction to half normal dose after 3 days if eGFR 15-30
- dose reduction to half normal dose if eGFR less than 15
dose of trimethoprim for prophylaxis of recurrent UTI
100mg OD, at night
alternatively 200mg 1 dose to be taken following exposure to trigger
dose of trimethoprim for catheter associated UTI
200mg BD for 7 days (14 days if upper UTI symptoms e.g. fever and loin pain are present)
dose of trimethoprim for lower UTI for female (obvs not pregnant because avoid in pregnancy)
200mg BD for 3 days
dose of trimethoprim for lower UTI for male
200mg BD for 7 days
contraindication for trimethoprim (1)
blood dyscrasia
interactions trimethoprim - MTX
avoid
increased risk of haematological SE (sometimes fatal)
interactions trimethoprim - warfarin
increase AC effect of warfarin
interactions digoxin and trimethoprim
T increases conc of digoxin
monitor digoxin conc
trimethoprim is …. toxic
nephrotoxic so increased risk of nephrotoxicity with other drugs e.g. antivirals, aspirin, amphotericin B, cephalosporins, Cs, NSAIDs, lithium, MTX , ACEi etc
trimethoprim interaction with ACEi and NSAIDs (2)
increased risk of nephrotoxicity
increased risk of HYPERkalaemia (esp notable with ACE or ARB given with spironolactone or eplerenone)
NSAIDs also increase risk of hyperkalameia as above
can you take clozapine with trimethoprim
no avoid as increased risk of neutropenia
monitoring requirements of trimethoprim
- blood counts with long term use and in those with or at risk of folate deficiency
- serum electrolytes in pt at risk of developing hyperkalaemia (e.g. ACE/ARB/NSAIDs/SEAT) and consider monitoring in other pt esp with long term use
- renal function esp with long term use
trimethoprim can cause the following electrolyte imbalance esp if given with SEAT, ACE, ARB, NSAIDs
hyperkalaemia
on long term treatment pt and their carers should be told how to recognise signs of blood disorders and are advised to seek immediate medical attention if symptoms e.g.
fever, sore throat, rash, mouth ulcers, purpura, bruising or bleeding develop.
choice of abx therapy for UTI in pregnancy
1st and 2nd line
Oral first line: Nitrofurantoin.
Oral second line (if no improvement after at least 48 hours, or first line not suitable):
Amoxicillin (only if culture susceptible), or cefalexin
prophylaxis of recurrent UTI - cefalexin dose
125mg OD, at ngiht
alternatively 500mg for one dose following exposure to a trigger
dose of cefalexin for lower UTI + in pregnancy
500mg BD for 3 days
pregnancy: 500mg BD for 7 days
cefalexin is ….toxic so….
nephrotoxic so combination with other nephrotoxic drugs (e.g. vancomycin, ACE, NSAIDs, antivirals, etc) increases risk
are blood disorders common SE of cefalexin
yes, all cephalosporins
what is methanamine hippurate and how does it work
urinary antiseptic agent
prevents urine infections as it has an antiseptic effect on urinary system
sterilises urine, stopping growth of certain bacteria
what is methanamine indicated for
prophylaxis and long term treatment of chronic or recurrent uncomplicated lower UTIs (+ in pt with catheters)
methanamine dose for prophylaxis and long term treatment of chronic or recurrent uncomplicated lower UTIs (+ in pt with catheters)
without catheter: 1g every 12 hours
with catheter: 1g every 8-12 hours
