Previous changes

March 2026 — minor update. Revised wording to increase the prominence of pre-term labour as a potential differential diagnosis.

February 2025 — minor update. Revised wording on nitrofurantoin in pregnancy to ensure consistency between prescribing sections.

December 2024 — minor update. Dosing of cefalexin in pregnancy updated to twice daily and choice of antibiotic in pregnancy. Information on seeking specialist advice and referral, and prescribing vaginal oestrogen has been updated, and a recommendation to consider offering methenamine hippurate has been added to the section on recurrent UTI in line with the updated NICE guideline Urinary tract infection (recurrent): antimicrobial prescribing.

October 2024 — minor update. Added information on MSU screening at booking appointments in intermediate and high-risk pregnancies to align with the NHS England document Saving babies’ lives: version 3 A care bundle for reducing perinatal mortality.

May 2024 — minor update. Revised information on prescribing in pregnancy to advise that nitrofurantoin should be avoided in the third trimester following communication from the UK Teratology Information Service. 

May 2024 — minor update. Minor typographical error corrected and severe cutaneous adverse reactions (SCAR) added as an adverse effect of pivmecillinam, as per the manufacturer's updated SPC. Drug interactions sections have also been updated.

December 2023 — reviewed. A literature search was conducted in October 2023 to identify evidence-based guidelines, UK policy, systematic reviews, and key randomized controlled trials published since the last revision of this topic. The recommendations have been updated in line with current evidence in the literature. The criteria used to diagnose urinary tract infection (UTI) and when to arrange dipstick testing of urine have been updated in line with the UK Health Security Agency (UKHSA) quick reference tool for primary care. The Scenario on the management of UTI with haematuria has been updated in line with the National Institute for Health and Care Excellence (NICE) guideline on Suspected cancer: recognition and referral (NICE 2023). The topic has undergone minor restructuring to improve clarity and navigation. The Prescribing information section has been expanded in line with current CKS style. Information on possible neurological adverse effects of cefalexin added in line with updated SPC.

June 2023 — minor update. The information relating to nitrofurantoin drug interactions has been updated in line with the manufacturer's summary of product characteristics (SPC). The interaction with dapsone and topical prilocaine has been removed.

March 2023 — minor update. The recommendation to screen for asymptomatic bacteriuria in pregnant women has been removed to align with the 2022 update of the NICE guideline Urinary tract infection (lower): antimicrobial prescribing (NG109).

February 2023 — minor update. The NICE quality standards have been updated. 

September 2022 — minor update. Broken links have been amended linking out to the Royal College of General Practitioners (RCGP) patient leaflets. Revised and removed the recommendation on repeat sampling for women with asymptomatic bacteriuria based on the 2022 update of the NICE guideline Urinary tract infection (lower): antimicrobial prescribing (NG109).

June 2021 — minor update. A typographical error has been corrected.

October 2020 — minor update. Information on dipstick testing has been added to the Basis for recommendation section on Assessment to improve clarity. 

December 2019 — minor update. Ectopic pregnancy has been added as a differential diagnosis.

October 2019 — minor update. Advice added to clarify asymptomatic bacteriuria should be confirmed with a repeat sample. 

January 2019 — reviewed. A literature search was conducted in October 2018 to identify evidence-based guidelines, UK policy, systematic reviews, and key RCTs published since the last revision of the topic. Changes to the recommendations have been made in line with updated guidance from the National Institute for Health and Care Excellence (NICE) Catheter-associated urinary tract infections: antimicrobial prescribing, Recurrent urinary tract infections: antimicrobial prescribing, and Urinary tract infections (lower): antimicrobial prescribing.

November 2018 — minor update. Changes made to bring the topic in line with the National Institute for Health and Care Excellence (NICE) guidance on Urinary tract infection (lower): antimicrobial prescribing and Urinary tract infection (recurrent): antimicrobial prescribing.

July 2015 — minor update. Links to the CKS topics on Analgesia - mild-to-moderate pain and NSAIDS - prescribing issues have been added to recommendations for providing symptom relief.

November 2014 — minor update to the Prescribing information section regarding the contraindication of use of nitrofurantoin in people with an estimated glomerular filtration rate (eGFR) of less than 45 mL/min/1.73 m².

August to November 2013 — reviewed. A literature search was conducted in August 2013 to identify evidence-based guidelines, UK policy, systematic reviews, and key RCTs published since the last revision of the topic. This CKS topic incorporates recommendations from the Scottish Intercollegiate Guidelines Network (SIGN) guideline Management of suspected bacterial urinary tract infection in adults: a national clinical guideline. There have been changes to the structure and minor changes to the recommendations. Cranberry products are no longer recommended for prophylaxis of recurrent UTI.

February 2013 — minor update. The 2013 QIPP options for local implementation have been added to this topic.

October 2012 — minor update. The 2012 QIPP options for local implementation have been added to this topic.

June 2011 — minor update. The 2010/2011 QIPP options for local implementation have been added to this topic. Changes to text regarding the safety of nitrofurantoin and trimethoprim in pregnancy. 

March 2011 — topic structure revised to ensure consistency across CKS topics. No changes to clinical recommendations have been made.

March 2011 — minor update. Minor clarification to the text.

December 2010 — minor update. Nitrofurantoin capsules have been added as an alternative to tablets in the Prescriptions. The Supporting evidence section on Nitrofurantoin formulations has also been updated.

September 2010 — minor update. In pregnant women with suspected symptomatic cystitis, amoxicillin is not recommended for empirical use, but is an option if the pathogen is reported to be susceptible. 

December 2009 — minor update. Dose of trimethoprim recommended for post-coital prophylaxis reduced to 100 mg stat. 

April to October 2009 — converted from CKS guidance to CKS topic structure. The evidence-base has been reviewed in detail, and recommendations are more clearly justified and transparently linked to the supporting evidence. There have been no major changes to the recommendations on treatment, although some major changes have been made to the structure. The approach to managing suspected cystitis reflects a change in focus from basing treatment decisions on accurate diagnosis to assessment of the person's risks and preferences.

October 2008 — minor update to reflect guidance from the Health Protection Agency (HPA) to avoid broad-spectrum antibiotics (such as co-amoxiclav, quinolones, and cephalosporins) when narrow-spectrum antibiotics remain effective, as broad-spectrum antibiotics increase the risk of Clostridium difficile, MRSA, and resistant UTIs. 

January to March 2006 — reviewed. Validated in June 2006 and issued in July 2006.

September 2008 — minor correction to the Changes section. 

May 2008 — minor update. Guidance updated to be in line with the SIGN guideline on the Management of suspected bacterial urinary tract infection in adults. 

November 2007 — minor update to clarify the use of trimethoprim in women who are pregnant or at risk of pregnancy.

November 2005 — minor technical update. 

July 2005 — updated to incorporate the Referral guidelines for suspected cancer published by the National Institute for Health and Care Excellence (NICE). 

January 2002 — written replacing previous guidance on UTI (lower) — acute and UTI (lower) — recurrent. Validated in March 2002 and issued in April 2002.

New evidence

Evidence-based guidelines

• AMRC (2024) Evidence-based Interventions Clinical Guidance. Release 4 - Urology. Academy of Medical Royal Colleges. [Free Full-text]

HTAs (Health Technology Assessments)

No new HTAs since 1 December 2023.

Economic Appraisals

No new economic appraisals since 1 December 2023.

Systematic reviews and meta-analyses

No new systematic reviews or meta-analysis which reach the CKS threshold for inclusion since 1 December 2023.

Primary evidence

• Wagenlehner, F., Perry, C. R., Hooton, T. M., Scangarella-Oman., et al. (2024). Oral gepotidacin versus nitrofurantoin in patients with uncomplicated urinary tract infection (EAGLE-2 and EAGLE-3): two randomised, controlled, double-blind, double-dummy, phase 3, non-inferiority trials. The Lancet. [Free Full-text]

New policies

NHS England Saving babies’ lives: version 3 A care bundle for reducing perinatal mortality, 2023 [Free full-text]. 

New safety alerts

No new safety alerts since 1 December 2023.

Changes in product availability

• New product EXBLIFEP 2 g/0.5 g powder is indicated for the treatment of complicated urinary tract infections (cUTI), including pyelonephritis. See more here.
• New Product fomicyt (fosfomycin) 40 mg/ml powder for solution for infusion is licensed in all age groups for the treatment of complicated urinary tract infections. See more here.

Basis for recommendation

The recommendations on when to suspect urinary tract infection (UTI) are based on the Scottish Intercollegiate Guidelines Network (SIGN) clinical guideline Management of suspected lower bacterial urinary tract infection in adult women [SIGN, 2020], the European Association of Urology (EAU) guideline Urological infections [EAU, 2023], and the UK Health Security Agency (UKSA) publications Diagnosis of urinary tract infections. Quick reference tool for primary care for consultation and local adaptation [UKHSA, 2020] and UK standards for microbiology investigations. Investigation of urine [UKHSA, 2019].

Basis for recommendation

The recommendations on assessment of urinary tract infection (UTI) are based on the National Institute for Health and Care Excellence (NICE) guidelines Urinary tract infection (lower): antimicrobial prescribing [NICE, 2022] and Urinary tract infection (catheter-associated): antimicrobial prescribing [NICE, 2019b], the Scottish Intercollegiate Guidelines Network (SIGN) clinical guideline Management of suspected lower bacterial urinary tract infection in adult women [SIGN, 2020], the European Association of Urology (EAU) guideline Urological infections [EAU, 2023], the UK Health Security Agency (UKHSA) publications Diagnosis of urinary tract infections. Quick reference tool for primary care for consultation and local adaptation [UKHSA, 2020] and UK standards for microbiology investigations. Investigation of urine [UKHSA, 2019], and expert opinion in review articles on urinary tract infection (UTI) in women [Hoffmann, 2021] and on the differential diagnosis of dysuria [Michels, 2015].

Basis for recommendation

The information on the differential diagnosis of urinary tract infection (UTI) is based on the National Institute for Health and Care Excellence (NICE) guideline Suspected cancer: recognition and referral [NICE, 2023b], the European Association of Urology (EAU) guideline Urological infections [EAU, 2023], the Scottish Intercollegiate Guidelines Network (SIGN) clinical guideline Management of suspected lower bacterial urinary tract infection in adult women [SIGN, 2020], the UK Health Security Agency (UKHSA) publication Diagnosis of urinary tract infections. Quick reference tool for primary care for consultation and local adaptation [UKHSA, 2020], and expert opinion in a review article on the differential diagnosis of dysuria [Michels, 2015]. It is also pragmatic, based on what CKS considers to be good clinical practice.

How should I manage suspected urinary tract infection (UTI)?

If a woman presents with suspected acute urinary tract infection (UTI):

• Arrange urgent hospital admission if:
  • There are severe systemic symptoms or signs suggesting a possible serious or life-threatening complication, such as pyelonephritis or sepsis.
  • The woman is unable to tolerate or adhere to treatment in primary care.
• Consider the need for immediate or delayed antibiotic treatment, depending on the woman's symptom severity, risk factors for complications, previous urine culture and susceptibility results, and previous antibiotic use.
  • If the woman has mild-to-moderate symptoms of uncomplicated UTI, consider giving advice about self-care measures instead of antibiotic treatment, depending on clinical judgement.
• If prescribing an immediate antibiotic, treat according to recent urine culture antibiotic susceptibilities (if available), otherwise, treat empirically, taking into account local antimicrobial resistance patterns, any contraindications or cautions, or potential drug interactions.
  • First-line, consider prescribing either of the following:
    • Nitrofurantoin 100 mg modified-release twice a day for 3 days.
    • Trimethoprim 200 mg twice a day for 3 days (if low risk of antimicrobial resistance).
  • Second-line, if there is no improvement in symptoms after at least 48 hours of first-line treatment, or first-line options are contraindicated or not tolerated, consider prescribing one of the following:
    • Nitrofurantoin 100 mg modified-release twice a day for 3 days (if not used first-line).
    • Pivmecillinam 400 mg initial dose, then 200 mg three times a day for a total of 3 days.
    • Fosfomycin 3 g single dose sachet.
  • Note: do not routinely prescribe antibiotic treatment for asymptomatic bacteriuria in a non-pregnant woman.
  • See the section on Prescribing information for detailed information on contraindications, cautions, adverse effects, and drug interactions for each antibiotic.
• Consider prescribing a delayed antibiotic if symptoms are mild and there are no risk factors for complicated UTI.
  • Advise to start treatment if symptoms do not start to improve within 48 hours or worsen at any time.
• Advise the woman on self-care measures for symptom relief.
  • Advise on the use of short-term over-the-counter simple analgesia such as paracetamol or ibuprofen, depending on any contraindications. See the CKS topics on Analgesia - mild-to-moderate pain and NSAIDs - prescribing issues for more information.
  • Maintain adequate hydration and aim to drink 1.5 L of water a day if there are no contraindications.
  • Do not recommend the use of over-the-counter cranberry products or urine alkalinising agents (such as potassium citrate, sodium citrate, or sodium bicarbonate).
• Advise on sources of information and support, such as:
  
  • The NHS (www.nhs.uk) patient information Urinary tract infections (UTIs).
  • The charity Bladder Health UK (www.bladderhealthuk.org) patient information Cystitis and UTIs.
  • The UK Health Security Agency (HSA) patient information UTI leaflet.
• Advise the woman to seek urgent medical review if symptoms worsen rapidly or significantly at any time or do not improve within 48 hours of starting antibiotic treatment.
  • Consider the possibility of an alternative diagnosis or complication, and manage accordingly. See the section on Differential diagnosis for more information.
  • Send a urine sample for culture and sensitivities (if not already done), and consider second-line antibiotic treatment while awaiting the results. See the section on Assessment for more information.
    • Review the choice of antibiotic when the results of susceptibility testing are available, if there is antimicrobial resistance and symptoms are not already improving, using a narrow-spectrum antibiotic where possible.

How should I manage suspected urinary tract infection (UTI) with haematuria?

If a woman presents with a suspected urinary tract infection (UTI) with visible or non-visible haematuria:

• Manage acute UTI symptoms depending on the woman's specific clinical situation.
  • Ensure that a urine sample for culture and susceptibility testing has been sent before starting antibiotic treatment, where appropriate. See the section on Assessment for more information.
  • See the Scenarios on Acute UTI, UTI in pregnancy, Asymptomatic bacteriuria in pregnancy, and Catheter-associated UTI for more information on management.
• Arrange an urgent urological referral using a 2-week wait pathway if a woman:
  • Is aged 45 years or over and has visible haematuria that persists or recurs after successful treatment of UTI.
  • Is aged 60 years and over and has unexplained non-visible haematuria and either dysuria or a raised white cell count on a blood test.
    • See the CKS topic on Urological cancers - recognition and referral for more information.
• Seek urgent specialist advice from an obstetrician regarding ongoing management if a woman:
  • Is pregnant and there is persistent haematuria after completion of antibiotic treatment for UTI. See the Scenario on UTI in pregnancy for more information.
• If a woman does not need urgent specialist referral or advice and there is any uncertainty about the possible underlying cause of haematuria, seek specialist advice about the need for further assessment and/or referral with a urologist or renal physician, depending on clinical judgement.

How should I manage recurrent urinary tract infection (UTI)?

If a woman presents with recurrent urinary tract infection (UTI):

• Manage acute UTI symptoms depending on the woman's specific clinical situation.
  • Ensure that a mid-stream urine (MSU) sample for culture and sensitivities has been sent before starting antibiotic treatment. See the section on Assessment for more information.
  • Consider the use of a self-initiated immediate short-course antibiotic treatment if the woman is able to self-diagnose and self-treat appropriately, depending on clinical judgement.
  • Do not routinely prescribe antibiotic treatment for asymptomatic bacteriuria in a non-pregnant woman with recurrent UTI.
  • See the Scenario on Acute UTI for more information on acute management of symptoms.
• Refer or seek specialist advice on further investigation and management for:
  • Trans women and non-binary people with a male genitourinary system aged 16 years and over.
  • People with recurrent upper UTI.
  • People with recurrent lower UTI when the underlying cause is unknown.
    • Consider arranging a non-urgent urological referral for bladder cancer for women aged 60 years and over with unexplained recurrent or persistent UTI.
  • Pregnant women, and pregnant trans men and non-binary people.
  • Children and young people aged under 16 years.
  • People with suspected cancer.
  • Anyone who has had gender reassignment surgery that involved structural alteration of the urethra. 
• Arrange specialist referral if there is a suspected underlying cause for recurrent UTI that needs specialist assessment or management, such as renal or ureteric stone disease, interstitial cystitis, or urogynaecological cancer. See the CKS topics on Renal or ureteric colic - acute, Urological cancers - recognition and referral, and Gynaecological cancers - recognition and referral for more information.
• Advise the woman on self-care measures for prevention of recurrent UTI.
  • Avoid or reduce risk factors for recurrent UTI where possible.
  • Maintain adequate hydration and aim to drink 1.5 L of water a day if there are no contraindications.
  • Avoid douching and wearing occlusive underwear.
  • Wipe the vulval and perineal areas from front to back after defecation.
  • Avoid delay of habitual and post-coital urination.
  • Do not recommend the use of over-the-counter cranberry products, urine alkalinising agents (such as potassium citrate, sodium citrate, or sodium bicarbonate), or D-mannose preparations.
• Advise the woman on sources of information and support, such as:
  • The charity Bladder Health UK (www.bladderhealthuk.org) patient information on Cystitis and UTIs, which includes information on recurrent UTI.
  • The UK Health Security Agency (HSA) patient information UTI leaflet.
• Consider prescribing topical vaginal oestrogen (off-label indication) for women, and trans men and non-binary people with a female urinary system, who are experiencing perimenopause or menopause, or who have already experienced menopause if behavioural and personal hygiene measures alone are not effective or not appropriate. 
  • Ensure they have been assessed for risk factors and investigated for underlying cause(s).
  • Discuss:
    • The severity and frequency of previous symptoms.
    • The risk of developing complications from recurrent UTIs.
    • The possible benefits of treatment, including for other related symptoms such as vaginal dryness.
    • That serious side effects are very rare.
    • That vaginal oestrogen is absorbed locally – a minimal amount is absorbed into the bloodstream, but this is unlikely to have a significant effect throughout the body.
    • The person's preferred treatment option for vaginal oestrogen (for example, a cream, gel, tablet, pessary or ring).
  • Review treatment with vaginal oestrogen within 12 months, or earlier if agreed with the person. See the CKS topic on Menopause for information on prescribing and monitoring of vaginal oestrogen preparations.
  • Do not offer systematic hormone replacement therapy (HRT) to reduce the risk of recurrent UTI. 
• Consider the use of antibiotic prophylaxis if the woman has been assessed for risk factors and underlying cause(s) and self-care measures and/or topical vaginal oestrogen (if indicated) are ineffective or not appropriate.
  • Take into account the severity and frequency of symptoms, the risk of complications, previous urine culture and susceptibility results, previous antibiotic use, and the woman’s preference for treatment.
  • Discuss the risks of long-term antibiotic treatment, including drug resistance and possible adverse effects.
  • Ensure that any current UTI has been adequately treated before starting antibiotic prophylaxis.
• Consider prescribing single-dose antibiotic prophylaxis for use when exposed to an identifiable trigger such as post-coital prophylaxis, taking into account local antimicrobial resistance patterns, any contraindications or cautions, and potential drug interactions.
  • First-line, prescribe trimethoprim 200 mg single dose, or nitrofurantoin 100 mg single dose.
  • Second-line, prescribe amoxicillin 500 mg single dose (off-label indication) or cefalexin 500 mg single dose.
  • See the section on Prescribing information for detailed information on contraindications, cautions, adverse effects, and drug interactions for each antibiotic.
• Consider prescribing a trial of low-dose daily antibiotic prophylaxis if there is no improvement after single-dose antibiotic prophylaxis or no identifiable triggers, taking into account local antimicrobial resistance patterns, any contraindications or cautions, and potential drug interactions.
  • First-line, prescribe trimethoprim 100 mg at night (if low risk of antimicrobial resistance) or nitrofurantoin 50–100 mg at night, depending on clinical judgement.
  • Second-line, prescribe amoxicillin 250 mg at night (off-label indication) or cefalexin 125 mg at night.
  • See the section on Prescribing information for detailed information on contraindications, cautions, adverse effects, and drug interactions for each antibiotic.
• Consider methenamine hippurate (1 g twice daily) as an alternative to daily antibiotic prophylaxis for recurrent UTI in women, and trans men and non-binary people with a female urinary system, if:
  • They are not pregnant and
  • Any current UTI has been adequately treated and
  • They have recurrent UTI that has not been adequately improved by behavioural and personal hygiene measures, vaginal oestrogen or single-dose antibiotic prophylaxis (if any of these have been appropriate and are applicable).
• Seek specialist advice if considering methenamine hippurate as an alternative to daily antibiotic prophylaxis for recurrent UTI:
  • During pregnancy.
  • In people with recurrent upper UTI or complicated lower UTI.
  • In trans women and non-binary people with a male genitourinary system.
• If discussing methenamine hippurate as a preventative treatment, explain that:
  • Over-the-counter sachets that make urine more alkaline (such as sachets used to relieve UTI symptoms that contain potassium citrate or sodium citrate) should not be used while taking methenamine hippurate because these can make the medicine less effective.
  • Medical help should be sought for acute UTI symptoms. 
• Review treatment with methenamine hippurate within 6 months, and then every 12 months, or earlier if agreed with the person.
• Arrange to follow-up the woman within 6 months of starting antibiotic prophylaxis.
  • Check symptom response and assess for any adverse effects.
  • Reinforce the importance of self-care measures.
  • Advise to seek urgent review if there are interim symptoms of acute UTI, and treat with a different antibiotic to that used for prophylaxis. See the section on Acute UTI for more information. 
  • Discuss the option of stopping or changing antibiotic prophylaxis, depending on symptom response and the risk of antimicrobial resistance.
    • If continuing antibiotic prophylaxis, consider rotating antibiotic choice, depending on local prescribing policies.
  • If there are ongoing recurrent UTIs despite adequate antibiotic prophylaxis, consider seeking specialist advice from the local microbiology department or arranging specialist urology referral, depending on clinical judgement.

How should I manage suspected urinary tract infection (UTI) in pregnancy?

If a woman has a suspected urinary tract infection (UTI) and is pregnant:

• Arrange urgent hospital admission if:
  • There are severe systemic symptoms or signs suggesting a possible serious or life-threatening complication, such as pyelonephritis or sepsis.
  • The woman is unable to tolerate or adhere to treatment in primary care.
  • There is clinical suspicion of impending labour. 
• Seek specialist advice or arrange referral if the person has:
  • Recurrent UTI diagnosed during pregnancy — refer to an obstetrician for investigation and follow-up.
  • A catheter-associated UTI.
  • A urine culture result showing an atypical or resistant organism.
  • An underlying structural or functional urinary tract abnormality or co-morbidity which increases the risk of complications or treatment failure.
  • A suspected serious underlying cause, such as renal disease or urogynaecological malignancy. See the CKS topics on Urological cancers - recognition and referral and Gynaecological cancers - recognition and referral for more information.
• If the woman has a first presentation of uncomplicated UTI, advise on self-care measures for symptom relief.
  • Advise on the use of over-the-counter simple analgesia such as paracetamol. See the CKS topic on Analgesia - mild-to-moderate pain for more information.
  • Advise on maintaining fluid balance to avoid dehydration.
  • Do not recommend use of over-the-counter cranberry products or urine alkalinising agents (such as potassium citrate, sodium citrate, or sodium bicarbonate).
• Prescribe an immediate antibiotic, taking into account previous urine culture antibiotic susceptibility results, previous antibiotic use, local antimicrobial resistance patterns, and any contraindications.
  • Ensure that a mid-stream urine (MSU) sample for culture and sensitivities has been sent before starting antibiotic treatment. See the section on Assessment for more information.
    • Consider prescribing antibiotics according to culture and sensitivity as follows:
      • First choice is nitrofurantion 100 mg modified-release twice daily for 7 days (avoid in third trimester).
      • Second choice is either cefalexin 500 mg twice a day for 7 days or amoxicillin 500 mg 3 times a day for 7 days.
    • Note: discuss with the local microbiology team if an alternative antibiotic is being considered, based on urine culture and susceptibility results, or if there is any uncertainty about antibiotic treatment.
  • See the section on Prescribing information for detailed information on contraindications, cautions, adverse effects, and drug interactions for each antibiotic in pregnancy.
• Advise the woman to seek urgent medical review if symptoms worsen rapidly or significantly at any time, or do not improve within 48 hours of starting antibiotic treatment.
  • Consider the possibility of an alternative diagnosis, and manage accordingly. See the section on Differential diagnosis for more information.
  • Consider prescribing second-line antibiotic treatment while awaiting the urine culture and sensitivities result.
  • Seek specialist advice and/or discuss with the local microbiology department if there is any uncertainty about ongoing management.
• Arrange to follow-up the woman, depending on clinical judgement.
  • Review the choice of antibiotic when the results of susceptibility testing are available if there is antimicrobial resistance, regardless of whether symptoms are improving or not, using a narrow-spectrum antibiotic where possible.
  • Arrange for a repeat urine sample to be sent for culture and susceptibility testing once antibiotic treatment is completed, to ensure clearance of infection. See the section on Assessment for more information.
  • Seek specialist advice if there is any uncertainty about ongoing management.
• If group B streptococcal bacteriuria is identified on urine culture, ensure the woman's midwife and obstetric team are also made aware, as intrapartum intravenous antibiotic prophylaxis should be offered in labour.

How should I manage asymptomatic bacteriuria in pregnancy?

In women who are assessed as being as having an intermediate or high risk category pregnancy, a midstream urine sample (MSU) should be taken and sent for culture and sensitivity at their booking appointment. 

If a woman is pregnant and has a urine culture result showing asymptomatic bacteriuria:

• Seek specialist advice if there are risk factors for complicated UTI.
• Prescribe an immediate antibiotic, taking into account recent urine culture and susceptibility testing results, any recent antibiotic use, local antimicrobial resistance patterns, and any contraindications.
  • Options include:
    
    • First choice is nitrofurantoin 100 mg modified-release twice a day for 7 days (not in third trimester).
    • Second choice is either amoxicillin 500 mg three times a day for 7 days (only if urine culture results show susceptibility) or cefalexin 500 mg twice a day for 7 days.
  • See the section on Prescribing information for detailed information on contraindications, cautions, adverse effects, and drug interactions for each antibiotic in pregnancy.
  • If there is any uncertainty about treatment options, seek specialist advice.
• Advise the woman to seek urgent medical review if any symptoms develop. See the section on UTI in pregnancy for more information.
• If group B streptococcal bacteriuria is identified on urine culture, ensure the woman's midwife and obstetric team are also made aware, as intrapartum intravenous antibiotic prophylaxis should be offered in labour.

How should I manage suspected catheter-associated urinary tract infection (UTI)?

If a woman has a suspected urinary tract infection (UTI) with a catheter in situ:

• Arrange urgent hospital admission if:
  • There are severe systemic symptoms or signs suggesting a possible serious or life-threatening complication, such as pyelonephritis or sepsis.
  • The woman is unable to tolerate or adhere to treatment in primary care.
• Arrange specialist referral or seek specialist advice if the woman has:
  
  • A risk factor for complicated UTI or treatment failure.
  • A history of recurrent catheter-associated UTI.
  • A urine culture result showing an atypical or resistant organism.
  • A suspected serious underlying cause, such as renal disease or urogynaecological malignancy. See the CKS topics on Urological cancers - recognition and referral and Gynaecological cancers - recognition and referral for more information.
• Advise the woman on self-care measures for symptom relief.
  • Advise on the use of over-the-counter simple analgesia such as paracetamol or ibuprofen, depending on any contraindications. See the CKS topics on Analgesia - mild-to-moderate pain and NSAIDs - prescribing issues for more information.
  • Maintain adequate hydration and aim to drink 1.5 litres a day if no contraindications.
  • Do not recommend use of over-the-counter cranberry products or urine alkalinising agents (such as potassium citrate, sodium citrate, or sodium bicarbonate).
• Advise on sources of information and support, such as:
  • The UK Health Security Agency (HSA) patient leaflet UTI -older adults.
  • The NHS (website www.nhs.uk) patient information Risks of a urinary catheter.
• Arrange for an indwelling urinary catheter to be ideally removed (or replaced) before starting antibiotic treatment, if possible.
  
  • If an indwelling catheter has been in situ for 7 days at the onset of UTI and is still needed, the catheter should be checked for leakage or blockage and replaced if it cannot be removed.
  • Ensure that a catheter urine sample for culture and susceptibility testing has been sent before starting antibiotic treatment, and include details of previous antibiotic use. See the section on Assessment for more information.
  • Do not routinely treat catheter-associated asymptomatic bacteriuria.
• Consider prescribing an antibiotic, taking into account the severity and frequency of symptoms, the risk of complications, previous urine culture and susceptibility results, previous antibiotic use, and local antimicrobial resistance patterns.
  • First-line, consider prescribing:
    • Nitrofurantoin 100 mg modified-release twice a day for 7 days, or
    • Trimethoprim 200 mg twice a day for 7 days (if low risk of antimicrobial resistance), or
    • Amoxicillin 500 mg three times a day for 7 days (only if urine culture results show susceptibility).
  • Second-line, if first-line treatment is contraindicated or not tolerated, consider prescribing:
    • Pivmecillinam 400 mg initial dose, then 200 mg three times a day for a total of 7 days.
  • See the section on Prescribing information for detailed information on contraindications, cautions, adverse effects, and drug interactions for each antibiotic.
    • Note: nitrofurantoin and pivmecillinam are only licensed for uncomplicated lower UTIs, and are not suitable for women with upper UTI symptoms or a blocked catheter.
• Advise to seek urgent medical review if symptoms worsen rapidly or significantly at any time, or do not improve within 48 hours of starting antibiotic treatment.
  • Consider the possibility of an alternative diagnosis or complication, and manage accordingly. See the section on Differential diagnosis for more information.
    
    • Review the choice of antibiotic when the results of urine culture susceptibility testing are available, if there is antimicrobial resistance, using a narrow-spectrum antibiotic where possible.
    • If there is any uncertainty about interpretation of urine culture results or treatment options, seek specialist advice, for example, from the local microbiology department.
• Ensure optimal long-term indwelling urinary catheter care.
  • Regularly reassess the need for ongoing catheterisation and arrange catheter removal if it is no longer clinically needed.
  • Advise to seek urgent review if there are interim symptoms of acute UTI.
  • Do not routinely change long-term indwelling catheters. Follow appropriate practices for catheter insertion and care.
  • Do not routinely prescribe antibiotic prophylaxis to prevent catheter-associated UTI in women with a long-term or short-term catheter in situ, or after catheter removal.
    • If antibiotic prophylaxis is being considered, seek specialist urology advice.

Contraindications and cautions

• Do not prescribe trimethoprim to women who:
  • Have severe hepatic insufficiency.
  • Have severe renal insufficiency.
  • Have megaloblastic anaemia or other blood dyscrasias — women taking long-term trimethoprim should be advised how to recognise the potential signs of blood disorders and should seek immediate medical attention if symptoms such as fever, sore throat, rash, mouth ulcers, purpura, bruising, or bleeding develop.
  • Are pregnant — trimethoprim is a folate antagonist, and there is a teratogenic risk in the first trimester of pregnancy. The manufacturer advises that it should not be used in women who are pregnant.
  • Have hereditary galactose intolerance, Lapp lactase deficiency, or glucose-galactose malabsorption.
• Prescribe trimethoprim with caution to women who:
  • Have impaired renal function — prescribe half the normal dose after 3 days if the eGFR (estimated glomerular filtration rate) is 15–30 mL/min/1.73m². Prescribe half the normal dose if the eGFR is less than 15 mL/min/1.73m².
  • Have hyperkalaemia or are taking medication known to cause hyperkalaemia, such as angiotensin-converting enzyme (ACE)-inhibitors, angiotensin-II receptor antagonists (AIIRAs), and diuretics — monitor electrolytes closely.
  • Have acute porphyria.
  • Are predisposed to folate deficiency — a folate supplement should be considered.

 [BNF, 2023; MHRA, 2023a]

Adverse effects

Possible adverse effects of trimethoprim include:

• Blood disorders — leukopenia, megaloblastic anaemia, thrombocytopenia, agranulocytosis, methaemoglobinaemia.
• Gastrointestinal — diarrhoea, nausea, vomiting (common), cholestatic jaundice.
• Nervous system — headache (common), dyskinesias, tremors, ataxia, dizziness, syncope, vertigo, tinnitus, aseptic meningitis (very rare).
• Skin and subcutaneous tissue — skin rashes, pruritus. More rarely, photosensitivity, exfoliative dermatitis, fixed drug eruption, erythema multiforme, erythema nodosum, Stevens-Johnson syndrome, toxic epidermal necrolysis, bullous dermatitis, purpura, angioedema.

[BNF, 2023; MHRA, 2023a]

Drug interactions

Potential drug interactions associated with trimethoprim include:

• Aciclovir — increased risk of nephrotoxicity.
• Amitriptyline — increased risk of hyponatraemia.
• Angiotensin-converting enzyme (ACE) inhibitors and angiotensin-II receptor antagonists (AIIRAs) — increased risk of hyperkalaemia. Monitor potassium concentrations.
• Azathioprine and mercaptopurine — increased risk of haematological toxicity, particularly if used for extended periods of time. Monitor the full blood count routinely.
• Carbamazepine — increased risk of hyponatraemia.
• Ciclosporin — serum creatinine levels may be increased. Possible increased risk of nephrotoxicity. Increased risk of hyperkalaemia. Monitor renal function closely.
• Citalopram, escitalopram, fluoxetine, and sertraline — increased risk of hyponatraemia.
• Coumarins (warfarin) — the anticoagulant effect of coumarins may be potentiated. Monitor international normalized ratio (INR) and adjust warfarin dose accordingly.
• Digoxin — digoxin levels may be increased if taken with trimethoprim, particularly in the elderly. Monitor for digoxin adverse effects, and adjust dose accordingly.
• Diuretics — hyperkalaemia may be exacerbated by concomitant administration of diuretics, particularly potassium-sparing diuretics, thiazide diuretics, and eplerenone.
• Methotrexate — there is an increased risk of haematologic adverse effects. Several cases of bone marrow suppression have been reported (some fatal). Full blood count should be monitored routinely.
• Nonsteroidal anti-inflammatory drugs (NSAIDs) — increased risk of hyponatraemia, hyperkalaemia, and nephrotoxicity.
• Phenytoin — phenytoin levels may be increased if taken with trimethoprim. Monitor phenytoin levels and adjust dose accordingly.
• Live cholera vaccines — the efficacy of the live vaccine may be affected. Avoid concurrent use and for 14 days before, and for 10 days after, live cholera vaccines.
• Live typhoid vaccines — the immune response to the vaccine may be reduced. Antibacterials should be stopped from 3 days before to 3 days after receiving live typhoid vaccines.

[BNF, 2023; Preston, 2023] 

Pregnancy and breastfeeding

• Pregnancy — do not prescribe trimethoprim to women who are pregnant.
  • Trimethoprim is a folate antagonist and there is a teratogenic risk in the first trimester of pregnancy. The manufacturer advises that it should not be used in women who are pregnant. UKTIS also advise against use in the first trimester but accept that it may be clinically appropriate second-line in the second and third trimesters. 
• Breastfeeding — short-term use of trimethoprim is not known to be harmful. Trimethoprim is present in breast milk.

[BNF, 2023; UKTIS, 2013]

Contraindications and cautions

• Do not prescribe nitrofurantoin to women who:
  • Have acute porphyria.
  • Have renal impairment — estimated glomerular filtration rate (eGFR) less than 45 mL/min/1.73 m².
  • Have glucose-6-phosphate dehydrogenase deficiency — nitrofurantoin is excreted in small amounts in breastmilk. Avoid breastfeeding during treatment with nitrofurantoin if a newborn is glucose-6-phosphate dehydrogenase deficient.
  • Are pregnant at term — risk of neonatal haemolysis.
• Prescribe nitrofurantoin with caution to women with:
  • Peripheral neuropathy or susceptibility to peripheral neuropathy, including folate deficiency — treatment should be stopped at the first signs of neural involvement (paraesthesiae).
  • Hepatic impairment — advise to be vigilant for symptoms and signs of liver dysfunction if taking nitrofurantoin for any duration, particularly with long-term use. Monitor for signs of hepatitis and liver function that may indicate hepatitis or liver injury.
  • Renal impairment — a short course of up to 7 days of nitrofurantoin may be used if the eGFR is 30–44 mL/min/1.73 m² and a urinary tract infection (UTI) has suspected or proven multi-drug resistance when the benefits of nitrofurantoin are considered to outweigh the risks of adverse effects.
  • Lung disease — advise to be vigilant for acute lung reactions in the first week of treatment. Women taking long-term nitrofurantoin should be monitored for signs of new or worsening respiratory symptoms, especially in the elderly (discontinue treatment immediately). Chronic pulmonary reactions (including pulmonary fibrosis and diffuse interstitial pneumonitis) can develop insidiously.
  • Anaemia.
  • Diabetes mellitus.
  • Electrolyte imbalance.

[BNF, 2023; EMC, 2023a; MHRA, 2023b] 

Adverse effects

Possible adverse effects of nitrofurantoin include:

• Blood and lymphatic system — aplastic anaemia (rare), agranulocytosis, leukopenia, thrombocytopenia, megaloblastic anaemia, methaemoglobinaemia.
• Gastrointestinal — nausea, diarrhoea, vomiting, abdominal pain, chronic active hepatitis, hepatic necrosis,  autoimmune hepatitis, cholestatic jaundice (rare).
• Respiratory, thoracic, and mediastinal disorders — pulmonary fibrosis, possible association with lupus-erythematous-like syndrome, acute pulmonary reactions, subacute pulmonary reactions, chronic pulmonary reactions, cough, and dyspnoea.
• Nervous system — benign cranial hypertension, peripheral neuropathy, nystagmus, vertigo, dizziness, headache, drowsiness.
• Skin and subcutaneous tissue — drug rash with eosinophilia and systemic symptoms (DRESS syndrome), lupus-like syndrome associated with pulmonary reaction, exfoliative dermatitis and erythema multiforme (including Stevens-Johnson syndrome); maculopapular, erythematous or eczematous eruptions; cutaneous vasculitis, urticaria, rash, pruritus, and transient alopecia.
• Musculoskeletal — arthralgia.

[BNF, 2023; EMC, 2023a; MHRA, 2023b] 

Drug interactions

Possible drug interactions associated with nitrofurantoin include:

• Alkalinising agents (for example potassium citrate and sodium bicarbonate ) — efficacy of nitrofurantoin may be decreased, although there is a lack of evidence to confirm this. Be alert for reduced efficacy. 
• Magnesium trisilicate — absorption of nitrofurantoin may be reduced. Monitor response.
• Quinolone antibiotics (for example, ciprofloxacin) — quinolones and nitrofurantoin are antagonists in vitro, but the clinical importance is uncertain.  
• Amiodarone, isoniazid, lamivudine, metronidazole, phenytoin, stavudine — can increase risk of peripheral neuropathy.
• Live cholera vaccines — the efficacy of the live vaccine may be affected. Avoid concurrent use and for 14 days before, and for 10 days after, live cholera vaccines.
• Live typhoid vaccines — the immune response to the vaccine may be reduced. Antibacterials should be stopped from 3 days before to 3 days after receiving live typhoid vaccines.

[BNF, 2023; Preston, 2023] 

Pregnancy and breastfeeding

• Pregnancy — do not prescribe nitrofurantoin to women who are pregnant at term — risk of neonatal haemolysis. 
• Breastfeeding — avoid use of nitrofurantoin in a woman who is breastfeeding. Nitrofurantoin is excreted in small amounts in breast milk, but enough to produce haemolysis in glucose-6-phosphate dehydrogenase deficient infants.

[BNF, 2023; UKTIS, 2013]

Contraindications and cautions

• Do not prescribe pivmecillinam to women who:
  • Have a true penicillin allergy — allergic reactions to penicillins occur in 1–10% of exposed people. Anaphylactic reactions occur in fewer than 0.05% of treated people.
    
    • Note: gastrointestinal adverse effects alone (for example nausea, vomiting, or diarrhoea) do not constitute an allergy to penicillin. See the CKS topic on Angio-oedema and anaphylaxis for more information.
  • Have a hypersensitivity to cephalosporins.
  • Have acute porphyria.
  • Have carnitine deficiency or concurrent treatment with valproic acid, valproate, or any other medication liberating pivalic acid due to increased risk of carnitine depletion.
  • Gastrointestinal obstruction.
  • Oesophageal strictures.

[BNF, 2023; EMC, 2023b] 

Adverse effects

Possible adverse effects of pivmecillinam include:

• Common adverse effects include diarrhoea, nausea (common), vomiting, abdominal pain, dyspepsia, vulvovaginal fungal infection.
• Uncommon adverse effects include dizziness, fatigue, gastrointestinal discomfort and disorders including antibiotic-associated colitis, headache, oral ulceration, severe cutaneous adverse reactions (SCAR), skin reactions, thrombocytopenia, vertigo, abnormal hepatic function.

[BNF, 2023; EMC, 2024]

Drug interactions

Possible drug interactions associated with pivmecillinam include:

• Methotrexate — pivmecillinam may reduce methotrexate clearance, causing an increased risk of toxicity.
  • Monitor methotrexate levels more closely. Consider twice-weekly platelet and white cell counts for two weeks initially, with the measurement of methotrexate levels if toxicity is suspected.
• Coumarin anticoagulants (warfarin and phenindione) — the effects of coumarins are not normally altered. It may be prudent to monitor the international normalized ratio (INR) within 3 days of starting or stopping a penicillin.
• Valproate — concurrent treatment with valproic acid, valproate, or other medication liberating pivalic acid increases the risk of carnitine depletion. Avoid concurrent use. If this is not possible, monitor closely.
• Live cholera vaccines — the efficacy of the live vaccine may be affected. Avoid concurrent use and for 14 days before, and for 10 days after, live cholera vaccines.
• Live typhoid vaccines — the immune response to the vaccine may be reduced. Antibacterials should be stopped from 3 days before to 3 days after receiving live typhoid vaccines.

[BNF, 2023; Preston, 2023] 

Pregnancy and breastfeeding

• Pregnancy — not known to be harmful, but manufacturer advises avoid use of pivmecillinam in pregnancy.
• Breastfeeding — trace amount in breast milk, but appropriate to use pivmecillinam if breastfeeding.

[BNF, 2023] 

Contraindications and cautions

• Do not prescribe fosfomycin to women with:
  • Severe renal insufficiency — avoid if creatinine clearance is 10 mL/min.
• Prescribe fosfomycin with caution to women who:
  • Are pregnant — manufacturer advises use only if potential benefit outweighs risk.
  • Are breastfeeding — manufacturer advises use only if potential benefit outweighs risk. Present in breast milk.

[BNF, 2023] 

Adverse effects

Possible adverse effects of fosfomycin include:

• Common adverse effects include abdominal pain, diarrhoea, headache, nausea, vomiting, dizziness, vulvovaginal infection.
• Uncommon adverse effects include skin reactions; antibiotic-associated colitis (frequency unknown).

[BNF, 2023] 

Drug interactions

• There are no common drug interactions associated with use of fosfomycin [BNF, 2023].

Pregnancy and breastfeeding

• Pregnancy — manufacturer advises use fosfomycin only if potential benefit outweighs risk.
• Breastfeeding — manufacturer advises use fosfomycin if breastfeeding only if potential benefit outweighs risk. Present in breast milk.

[BNF, 2023] 

Contraindications and cautions

• Do not prescribe amoxicillin to women with:
  • A true penicillin allergy — allergic reactions to penicillins occur in 1–10% of exposed people. Anaphylactic reactions occur in fewer than 0.05% of treated people.
    • Note: gastrointestinal adverse effects alone (for example nausea, vomiting, or diarrhoea) do not constitute an allergy to penicillin. See the CKS topic on Angio-oedema and anaphylaxis for more information.
  • Hypersensitivity to cephalosporins.
• Prescribe amoxicillin with caution to women with:
  • Renal impairment — reduce the dose of amoxicillin in severe impairment.
  • Cytomegalovirus — increased risk of erythematous rashes.
  • Glandular fever (infectious mononucleosis) — erythematous rashes are common following the use of amoxicillin.
  • Acute lymphocytic leukaemia and chronic lymphocytic leukaemia — increased risk of erythematous rashes.

[BNF, 2023; EMC, 2023c] 

Adverse effects

Possible adverse effects of amoxicillin include:

• Gastrointestinal — nausea, diarrhoea (common), vomiting (uncommon), antibiotic-associated colitis (very rare).
• Skin and subcutaneous tissue — skin rash (common), urticaria and pruritus (uncommon). Very rarely erythema multiforme, Stevens-Johnson syndrome, toxic epidermal necrolysis, bullous and exfoliative dermatitis, and acute generalised exanthematous pustulosis.
• Other — hepatitis, cholestatic jaundice; hyperkinesia, dizziness, convulsions; interstitial nephritis; leukopenia, thrombocytopenia, haemolytic anaemia.

[BNF, 2023; EMC, 2023c] 

Drug interactions

Possible drug interactions associated with use of amoxicillin include:

• Allopurinol — increased risk of rash when allopurinol is given with amoxicillin. It is not necessary to avoid concurrent use.
• Methotrexate — amoxicillin may reduce methotrexate clearance, causing an increased risk of toxicity.
  • Monitor methotrexate levels more closely. One recommendation is to carry out twice-weekly platelet and white cell counts for 2 weeks initially, with the measurement of methotrexate levels if toxicity is suspected.
• Coumarin anticoagulants (warfarin and phenindione) — the international normalized ratio (INR) may be increased. Monitor the INR within 3 days of starting or stopping amoxicillin.
• Live cholera vaccines — the efficacy of the live vaccine may be affected. Avoid concurrent use and for 14 days before, and for 10 days after, live cholera vaccines.
• Live typhoid vaccines — the immune response to the vaccine may be reduced. Antibacterials should be stopped from 3 days before to 3 days after receiving live typhoid vaccines.

[BNF, 2023; Preston, 2023] 

Pregnancy and breastfeeding

• Pregnancy — amoxicillin is not known to be harmful in pregnancy.
• Breastfeeding — trace amount of amoxicillin in breast milk, but appropriate to use.

[BNF, 2023] 

Contraindications and cautions

• Do not prescribe cefalexin to women with:
  • A known allergy to the cephalosporin group of antibiotics or a history of immediate hypersensitivity to penicillin and other beta-lactams.
• Prescribe cefalexin with caution to women with:
  • Sensitivity to penicillin and other beta-lactams — up to 10% of penicillin-sensitive people will also be allergic to first- and early second-generation cephalosporins and 2-3% for third-generation cephalosporins. 

[BNF, 2023]

Adverse effects

Possible adverse effects associated with cefalexin include:

• Gastrointestinal — diarrhoea (most common), nausea, vomiting, abdominal discomfort.
• Nervous system — headache, dizziness.
  • Tremor, myoclonia, convulsions, encephalopathy have also been reported — most cases occurred in patients with renal impairment on doses above the recommended maximum and resolved following discontinuation. 
• Psychiatric — hallucinations, confusion, agitation.
• Skin — urticaria, angioedema. Rarely erythema multiforme, Stevens-Johnson syndrome and toxic epidermal necrolysis.
• Other — anaphylaxis; arthralgia and myalgia; eosinophilia, neutropenia, thrombocytopenia, haemolytic anaemia; genital and anal pruritus; hepatitis, cholestatic jaundice; interstitial nephritis (rare); antibiotic-associated colitis. See the CKS topic on Diarrhoea - antibiotic associated for more information.

[BNF, 2023]

Drug interactions

Possible drug interactions associated with use of cefalexin include:

• Aciclovir — concomitant use can increase the risk of nephrotoxicity.
• Aminoglycosides (for example gentamicin) — possible increased risk of nephrotoxicity. Routine renal monitoring for the aminoglycoside is usually adequate.
• Angiotensin-converting enzyme (ACE) inhibitors — concomitant use can increase the risk of nephrotoxicity.
• Ciclosporin — concomitant use can increase the risk of nephrotoxicity.
• Methotrexate — concomitant use can increase the risk of nephrotoxicity.
• Nonsteroidal anti-inflammatory drugs (NSAIDs) — concomitant use can increase the risk of nephrotoxicity.
• Coumarin anticoagulants (warfarin and phenindione) — cefalexin may enhance the anticoagulant effect. Monitor the international normalized ratio (INR) closely during concomitant use.
• Probenecid — renal excretion of cefalexin is inhibited. However, no dose adjustment is normally required.
• Live cholera vaccines — the efficacy of the live vaccine may be affected. Avoid concurrent use and for 14 days before, and for 10 days after, live cholera vaccines.
• Live typhoid vaccines — the immune response to the vaccine may be reduced. Antibacterials should be stopped from 3 days before to 3 days after receiving live typhoid vaccines.

[BNF, 2023; Preston, 2023] 

Pregnancy and breastfeeding

• Pregnancy — cefalexin is not known to be harmful in pregnancy.
• Breastfeeding — cefalexin is present in breast milk in low concentrations, but is appropriate to use if a woman is breastfeeding.

[BNF, 2023]