Summary of antimicrobial guidance

Summary of antimicrobial prescribing guidance - managing common infections

Version 1.2, September 2024

UKHSA, NICE and other collaborators are discussing options for continued production of the Summary of Antimicrobial Prescribing Guidance (previously hosted by BNF Publications). In the interim we have produced a list of the conditions in the table linked to available national guidance.

We and have also included a condensed version of the table summary that includes infections covered by NICE antimicrobial prescribing guidance.

• Click to view the full condensed summary of antimicrobial prescribing guidance – table

Please refer to the user guide and principles of treatment when using the antimicrobial prescribing guidance summaries.

Fluoroquinolone antibiotics: In January 2024, the MHRA published a Drug Safety Update on fluoroquinolone antibiotics. These must now only be prescribed when other commonly recommended antibiotics are inappropriate. Stakeholders are assessing the impact of this warning on recommendations in the relevant guidance.

• Click to view updates to content within the table summary (PDF file, 180 KB)

Please contact the TARGET team at TARGETantibiotics@UKHSA.gov.uk for additional information if required.

• Acne vulgaris – NICE
• Acute cough - NICE
• Acute otitis media - NICE
• Acute otitis externa – NICE/CKS
• Acute sore throat - NICE
• Bacterial vaginosis – BASHH
• Blepharitis – NICE/CKS
• Boils, carbuncles, and staphylococcal carriage - NICE/CKS
• Bronchiectasis (non-cystic fibrosis), acute exacerbation - NICE
• Candida – oral – NICE/CKS
• Cellulitis and erysipelas - NICE
• Chlamydia - BASHH
• Chickenpox – NICE/CKS
• Clostridioides difficile infection - NICE
• Conjunctivitis – NICE/CKS
• COPD (acute exacerbation) - NICE
• Coronavirus (COVID-19) - NICE
• Diabetic foot infection - NICE
• Diarrhoea – prevention and advice for travellers – NICE/CKS
• Diverticular disease - NICE
• Eczema - NICE
• Epididymitis - BASHH
• Fungal skin infection: body and groin – NICE/CKS
• Fungal skin infection: nail – NICE/CKS
• Gastroenteritis - NICE/CKS
• Gonorrhoea - BASHH
• Helicobacter pylori - NICE/BNF
• Herpes – genital - BASHH
• Herpes simplex – oral – NICE/CKS
• Human and animal bites - NICE
• Impetigo - NICE
• Influenza - UKHSA/CKS
• Insect bites and stings - NICE
• Leg ulcer - NICE
• Mastitis – NICE/CKS
• Pelvic inflammatory disease – BASHH
• Pneumonia (community-acquired) - NICE
• Pneumonia (hospital-acquired) - NICE
• Prostatitis (acute) - NICE
• PVL-SA - UKHSA (PHE)
• Pyelonephritis (acute) - NICE
• Scabies - BASHH
• Scarlet fever - NICE/CKS
• Shingles – NICE/CKS
• Sinusitis - NICE
• Suspected meningococcal disease – NICE/CKS
• Threadworm – NICE/CKS
• Tick bites (Lyme disease) - NICE
• Trichomoniasis - BASHH
• UTI (lower) - NICE
• UTI (recurrent) - NICE
• UTI (catheter-associated) - NICE
• Vaginal candidiasis - BASHH

Upper Respiratory Tract Infection text summaries

Please refer to the user guide and principles of treatment when using the antimicrobial prescribing guidance summaries.

Contents

Lower Respiratory Tract Infection text summaries

Please refer to the user guide and principles of treatment when using the antimicrobial prescribing guidance summaries.

Contents

COVID-19

Antibiotics should not be used for preventing or treating COVID-19 unless there is clinical suspicion of additional bacterial co-infection.

Do not use azithromycin to treat COVID-19.

Do not use doxycycline to treat COVID-19 in the community.

Do not offer an antibiotic for preventing secondary bacterial pneumonia in people with COVID-19.

If a person in the community has suspected or confirmed secondary bacterial pneumonia, start antibiotic treatment as soon as possible, see community-acquired pneumonia for choices.

In hospital, start empirical antibiotics if there is clinical suspicion of a secondary bacterial infection in people with COVID-19, see hospital-acquired pneumonia for choices. Start antibiotics as soon as possible after establishing a diagnosis of secondary bacterial pneumonia, and certainly within 4 hours. Start treatment within 1 hour if the person has suspected sepsis and meets any of the high-risk criteria for this outlined in the NICE guideline on sepsis.

For detailed information, see the NICE guideline on managing COVID-19.

Section last updated: December 2021

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Acute Exacerbation of COPD

Many exacerbations are not caused by bacterial infections so will not respond to antibiotics.

Consider an antibiotic, but only after taking into account severity of symptoms (particularly sputum colour changes and increases in volume or thickness), need for hospitalisation, previous exacerbations, hospitalisations and risk of complications, previous sputum culture and susceptibility results, and risk of resistance with repeated courses.

Some people at risk of exacerbations may have antibiotics to keep at home as part of their exacerbation action plan.

First choice adult:        

amoxicillin 500mg TDS (see BNF for severe infection) for 5 days

OR

doxycycline 200mg on day 1, then 100mg OD (see BNF for severe infection) for 5 days

OR

clarithromycin 500mg BD for 5 days

Second choice adult:     use alternative first choice

Alternative choice adult (if person at higher risk of treatment failure):

co-amoxiclav 500/125mg TDS for 5 days

OR

co-trimoxazole 960mg BD for 5 days

OR

levofloxacin (only if other alternative choice antibiotics are unsuitable with specialist advice) 500mg OD for 5 days. 

See the MHRA January 2024 advice on restrictions and precautions for using fluoroquinolone antibiotics because of the risk of disabling and potentially long-lasting or irreversible side effects. Fluoroquinolones must now only be prescribed when other commonly recommended antibiotics are inappropriate.

IV antibiotics: see the guidance visual summary

For detailed information,  see the guidance visual summary or https://www.nice.org.uk­­­­/guidance/ng115

NICE

Section last updated September 2024

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Acute Exacerbation of Bronchiectasis (Non-Cystic Fibrosis)

Send a sputum sample for culture and susceptibility testing.

Offer an antibiotic.

When choosing an antibiotic, take account of severity of symptoms and risk of treatment failure. People who may be at higher risk of treatment failure include people who’ve had repeated courses of antibiotics, a previous sputum culture with resistant or atypical bacteria, or a higher risk of developing complications.

Course length is based on severity of bronchiectasis, exacerbation history, severity of exacerbation symptoms, previous culture and susceptibility results, and response to treatment.

Do not routinely offer antibiotic prophylaxis to prevent exacerbations.

Seek specialist advice for preventing exacerbations in people with repeated acute exacerbations. This may include a trial of antibiotic prophylaxis after a discussion of the possible benefits and harms, and the need for regular review.

First choice empirical treatment adult:

amoxicillin (preferred if pregnant) 500mg TDS for 7 to 14 days

OR

doxycycline (not in under 12s) 200mg on day 1, then 100mg OD for 7 to 14 days

OR

clarithromycin 500mg BD for 7 to 14 days

Alternative choice (if person is at higher risk of treatment failure) empirical treatment adult:

co-amoxiclav 500/125mg TDS for 7 to 14 days

OR

levofloxacin (adults only: with specialist advice if con-amoxiclav cannot be used: consider safety issues) 500mg OD or BD 7 to 14 days

OR

levofloxacin (adults only: only if con-amoxiclav is unsuitable; with specialist advice) 500mg OD or BD 7 to 14 days

See the MHRA January 2024 advice on restrictions and precautions for using fluoroquinolone antibiotics because of the risk of disabling and potentially long-lasting or irreversible side effects. Fluoroquinolones must now only be prescribed when other commonly recommended antibiotics are inappropriate.

IV antibiotics: see the guidance visual summary

When current susceptibility data available: choose antibiotics accordingly

For information on children’s dosage or for detailed information see the guidance visual summary or https://www.nice.org.uk/guidance/ng117/

NICE

Section last updated September 2024

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Acute Cough 

Some people may wish to try honey (in over 1s), the herbal medicine pelargonium (in over 12s), cough medicines containing the expectorant guaifenesin (in over 12s) or cough medicines containing cough suppressants, except codeine, (in over 12s). These self-care treatments have limited evidence for the relief of cough symptoms.

Acute cough with upper respiratory tract infection: no antibiotic.

Acute bronchitis: no routine antibiotic.

Acute cough and higher risk of complications (at face-to-face examination): immediate or back-up antibiotic.

Acute cough and systemically very unwell (at face-to-face examination): immediate antibiotic.

Higher risk of complications includes people with pre-existing comorbidity; young children born prematurely; people over 65 with 2 or more of, or over 80 with 1 or more of: hospitalisation in previous year, type 1 or 2 diabetes, history of congestive heart failure, current use of oral corticosteroids.

Do not offer a mucolytic, an oral or inhaled bronchodilator, or an oral or inhaled corticosteroid unless otherwise indicated.

First choice adults:      

doxycycline 200mg day1, then 100mg OD for 5 days

Alternative first choice adults:

amoxicillin (preferred if pregnant) 500mg TDS for 5 days

OR

clarithromycin 250mg to 500mg BD for 5 days

OR

erythromycin (if macrolide needed in pregnancy; consider benefit/harm) 250mg to 500mg QDS or 500mg to 1000mg BD for 5 days

First choice children: 

amoxicillin for 5 days

Alternative first choice children: 

clarithromycin for 5 days

OR

erythromycin for 5 days

OR

doxycycline (not in under 12s) for 5 days

For information on children’s dosage or for detailed information see the guidance visual summary or https://www.nice.org.uk/guidance/ng120

NICE

Section last updated Feb 2019

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Hospital-Acquired Pneumonia

If symptoms or signs of pneumonia start within 48 hours of hospital admission, see community acquired pneumonia.

Offer an antibiotic. Start treatment as soon as possible after diagnosis, within 4 hours (within 1 hour if sepsis suspected and person meets any high-risk criteria – see the NICE guideline on sepsis).

When choosing an antibiotic, take account of severity of symptoms or signs, number of days in hospital before onset of symptoms, risk of developing complications, local hospital and ward-based antimicrobial resistance data, recent antibiotic use and microbiological results, recent contact with a health or social care setting before current admission, and risk of adverse effects with broad spectrum antibiotics.

No validated severity assessment tools are available. Assess severity of symptoms or signs based on clinical judgement.

Higher risk of resistance includes relevant comorbidity (such as severe lung disease or immunosuppression), recent use of broad-spectrum antibiotics, colonisation with multi-drug resistant bacteria, and recent contact with health and social care settings before current admission.

If symptoms or signs of pneumonia start within days 3 to 5 of hospital admission in people not at higher risk of resistance, consider following community acquired pneumonia for choice of antibiotic.

First choice adults and children (non-severe and not higher risk of resistance):

co-amoxiclav for adults 500/125mg TDS for 5 days then review

co-amoxiclav for children see the guidance visual summary for children’s dosage

Alternative first choice adults (non-severe and not higher risk of resistance):

choice based on specialist microbiological advice and local resistance data

Options include:

doxycycline 200mg on day 1, then 100mg OD for 5 days then review

OR

cefalexin (caution in penicillin allergy) 500 mg BD or TDS (can increase to 1 to 1.5g TDS or QDS for 5 days then review

OR

co-trimoxazole 960mg BD for 5 days then review

OR

levofloxacin (only if switching from IV levofloxacin with specialist advice;) 500mg OD or BD for 5 days then review

See the MHRA January 2024 advice on restrictions and precautions for using fluoroquinolone antibiotics because of the risk of disabling and potentially long-lasting or irreversible side effects. Fluoroquinolones must now only be prescribed when other commonly recommended antibiotics are inappropriate.

Children alternative first choice (non-severe and not higher risk of resistance): clarithromycin

other options may be suitable based on specialist microbiological advice and local resistance data

see the guidance visual summary for children’s dosage

For first choice IV antibiotics (severe or higher risk of resistance) and antibiotics to be added if suspected or confirmed MRSA infection see visual summary.

For detailed information see the guidance visual summary or https://www.nice.org.uk/guidance/ng139

NICE

Section last updated September 2024

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Community-Acquired Pneumonia

Assess severity in adults based on clinical judgement and guided by a mortality risk score (CRB65 or CURB65) when these scores can be calculated:

• low severity – CRB65 0 or CURB65 0 or 1
• moderate severity – CRB65 1 or 2 or CURB65 2
• high severity – CRB65 3 or 4 or CURB65 3 to 5.

1 point for each parameter: confusion, urea (>7 mmol/l), respiratory rate ≥30/min, low systolic (<90 mm Hg) or diastolic (≤60 mm Hg) blood pressure, age ≥65.

Assess severity in children based on clinical judgement.

Offer an antibiotic. Start treatment as soon as possible after diagnosis, within 4 hours (within 1 hour if sepsis suspected and person meets any high-risk criteria – see the NICE guideline on sepsis).

When choosing an antibiotic, take account of severity, risk of complications, local antimicrobial resistance and surveillance data, recent antibiotic use, and microbiological results.

First choice (low severity in adults or non-severe in children):

amoxicillin for adults 500mg TDS (higher doses can be used, see BNF) for 5 days

Stop antibiotics after five days unless microbiological results suggest a longer course is needed or the person is not clinically stable

amoxicillin for children see the guidance visual summary for age range and dosage

Alternative first choice (low severity in adults or non-severe in children):

doxycycline for adults 200mg on day 1, then 100mg OD for 5 days

Stop antibiotics after five days unless microbiological results suggest a longer course is needed or the person is not clinically stable

doxycycline for children (not in under 12s) see the guidance visual summary for age range and dosage

OR

clarithromycin 500mg BD for 5 days

Stop antibiotics after five days unless microbiological results suggest a longer course is needed or the person is not clinically stable

clarithromycin for children see the guidance visual summary for age range and dosage

OR

erythromycin (if macrolide needed in pregnancy; consider benefit/harm) 500mg QDS for 5 days

Stop antibiotics after five days unless microbiological results suggest a longer course is needed or the person is not clinically stable

erythromycin (if macrolide needed in pregnancy; consider benefit/harm) for children see the guidance visual summary for age range and dosage

First choice (moderate severity in adults):

amoxicillin 500mg TDS (higher doses can be used, see BNF) for 5 days

Stop antibiotics after five days unless microbiological results suggest a longer course is needed or the person is not clinically stable

With either (if atypical pathogens suspected)

clarithromycin 500mg BD for 5 days

Stop antibiotics after five days unless microbiological results suggest a longer course is needed or the person is not clinically stable

OR

erythromycin (if macrolide needed in pregnancy; consider benefit/harm) 500mg QDS for 5 days

Stop antibiotics after five days unless microbiological results suggest a longer course is needed or the person is not clinically stable

Alternative first choice (moderate severity in adults):

doxycycline 200mg on day 1, then 100mg OD for 5 days

Stop antibiotics after five days unless microbiological results suggest a longer course is needed or the person is not clinically stable

OR

clarithromycin 500mg BD for 5 days

Stop antibiotics after five days unless microbiological results suggest a longer course is needed or the person is not clinically stable

First choice (high severity in adults or severe in children):

co-amoxiclav 500/125mg TDS for 5 days

Stop antibiotics after five days unless microbiological results suggest a longer course is needed or the person is not clinically stable

co-amoxiclav for children see the guidance visual summary for age range and dosage

With either (if atypical pathogens suspected)

clarithromycin 500mg BD for 5 days

Stop antibiotics after five days unless microbiological results suggest a longer course is needed or the person is not clinically stable

clarithromycin for children see the guidance visual summary for age range and dosage

OR

erythromycin (if macrolide needed in pregnancy; consider benefit/harm) 500mg QDS for 5 days

Stop antibiotics after five days unless microbiological results suggest a longer course is needed or the person is not clinically stable

erythromycin for children (if macrolide needed in pregnancy; consider benefit/harm) see the guidance visual summary for age range and dosage

Alternative antibiotic if high severity, for penicillin allergy:

levofloxacin 500mg BD for 5 days. Stop antibiotics after five days unless microbiological results suggest a longer course is needed or the person is not clinically stable

See the MHRA January 2024 advice for restrictions and precautions on using fluoroquinolone antibiotics because of the risk of disabling and potentially long-lasting or irreversible side effects.

IV antibiotics: check the guidance visual summary

For detailed information or for information on children’s dosage see the guidance visual summary or see https://www.nice.org.uk/guidance/ng138/

NICE

Section last updated September 2024

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Urinary Tract Infection text summaries

Please refer to the user guide and principles of treatment when using the antimicrobial prescribing guidance summaries.

Contents

Lower Urinary Tract Infection

Advise paracetamol or ibuprofen for pain.

Non-pregnant women: back up antibiotic (to use if no improvement in 48 hours or symptoms worsen at any time) or immediate antibiotic.

Pregnant women, men, children, or young people: immediate antibiotic.

When considering antibiotics, take account of severity of symptoms, risk of complications, previous urine culture and susceptibility results, previous antibiotic use which may have led to resistant bacteria and local antimicrobial resistance data.

If people have symptoms of pyelonephritis (such as fever) or a complicated UTI, see acute pyelonephritis (upper urinary tract infection) for antibiotic choices.

Non-pregnant adult women first choice:

nitrofurantoin (if eGFR ≥45 ml/minute) 100mg m/r BD (or if unavailable 50mg QDS) for 3 days

OR

trimethoprim (if low risk of resistance) 200mg BD for 3 days

Non-pregnant adult women second choice:

nitrofurantoin (if eGFR ≥45 ml/minute) 100mg m/r BD (or if unavailable 50mg QDS) for 3 days

OR

pivmecillinam (a penicillin) 400mg initial dose, then 200mg TDS for 3 days

OR

fosfomycin 3g single dose sachet single dose

Pregnant adult women first choice:

nitrofurantoin (avoid at term) – if eGFR ≥45 ml/minute 100mg m/r BD (or if unavailable 50mg QDS) for 7 days

Pregnant adult women second choice:

amoxicillin (only if culture results available and susceptible) 500mg TDS for 7 days

OR

cefalexin 500mg BD for 7 days

Treatment of asymptomatic bacteriuria in pregnant adult women:

choose from nitrofurantoin (avoid at term), amoxicillin or cefalexin based on recent culture and susceptibility results

Adult men first choice:

trimethoprim 200mg BD for 7 days

OR

nitrofurantoin (if eGFR ≥45 ml/minute) 100mg m/r BD (or if unavailable 50mg QDS) for 7 days

Adult men second choice:   

consider alternative diagnoses basing antibiotic choice on recent culture and susceptibility results

Children and young people (3 months and over) first choice:

trimethoprim (if low risk of resistance)

OR

nitrofurantoin (if eGFR ≥45 ml/minute)

Children and young people (3 months and over) second choice:

nitrofurantoin (if eGFR ≥45 ml/minute and not used as first choice)

OR

amoxicillin (only if culture results available and susceptible)

OR

cefalexin

For information on children’s dosage see the guidance visual summary or  https://www.nice.org.uk/guidance/ng138/.

NICE

For detailed information see the guidance visual summary or  https://www.nice.org.uk/guidance/ng138/.

See also the NICE guideline on urinary tract infection in under 16s: diagnosis and management and the UK Health Security Agency urinary tract infection: diagnostic tools for primary care.

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Acute Pyelonephritis (Upper Urinary Tract)

Advise paracetamol (+/- low-dose weak opioid) for pain for people over 12.

Offer an antibiotic.

When prescribing antibiotics, take account of severity of symptoms, risk of complications, previous urine culture and susceptibility results, previous antibiotic use which may have led to resistant bacteria and local antimicrobial resistance data.

Avoid antibiotics that don’t achieve adequate levels in renal tissue, such as nitrofurantoin.

Non-pregnant women and men first choice:

cefalexin 500mg BD or TDS (up to 1g to 1.5g TDS or QDS for severe infections) for 7 to 10 days

OR

co-amoxiclav (only if culture results available and susceptible) 500/125mg TDS for 7 to 10 days

OR

trimethoprim (only if culture results available and susceptible) 200mg BD for 14 days

OR

ciprofloxacin (only if other first choice antibiotics are unsuitable) 500mg BD for 7 days 

See the MHRA January 2024 advice on restrictions and precautions for using fluoroquinolone antibiotics because of the risk of disabling and potentially long-lasting or irreversible side effects. Fluoroquinolones must now only be prescribed when other commonly recommended antibiotics are inappropriate.

Non-pregnant women and men IV antibiotics:

see the guidance visual summary

Pregnant women first choice:

cefalexin 500mg BD or TDS (up to 1g to 1.5g TDS or QDS for severe infections) for 7 to 10 days

Pregnant women second choice or IV antibiotics:

see the guidance visual summary

Children and young people (3 months and over) first choice: 

cefalexin

OR

co-amoxiclav (only if culture results available and susceptible)

Children and young people (3 months and over) IV antibiotics: see the guidance visual summary

For information on children’s dosage or for detailed information see the guidance visual summary or https://www.nice.org.uk/guidance/ng111/.

NICE

For detailed information click on the guidance visual summary. See also the NICE guideline on urinary tract infection in under 16s: diagnosis and management and the UK Health Security Agency urinary tract infection: diagnostic tools for primary care.

Section last updated September 2024

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Acute Prostatitis

Advise paracetamol (+/- low-dose weak opioid) for pain, or ibuprofen if preferred and suitable.

Offer antibiotic.

Review antibiotic treatment after 14 days and either stop antibiotics or continue for a further 14 days if needed (based on assessment of history, symptoms, clinical examination, urine, and blood tests).

First choice adult (guided by susceptibilities when available):

ciprofloxacin 500mg BD for 14 days then review

See the MHRA January 2024 advice on restrictions and precautions for using fluoroquinolone antibiotics because of the risk of disabling and potentially long-lasting or irreversible side effects.

OR

ofloxacin 200mg BD for 14 days then review

See the MHRA January 2024 advice on restrictions and precautions for using fluoroquinolone antibiotics because of the risk of disabling and potentially long-lasting or irreversible side effects.

Alternative first choice if fluoroquinolone antibiotic is not appropriate (seek specialist advice; guided by susceptibilities when available):

trimethoprim (if fluoroquinolone not appropriate; seek specialist advice) 200mg BD for 14 days then review

Second choice adult (after discussion with specialist):

levofloxacin 500mg OD for 14 days then review 

See the MHRA January 2024 advice on restrictions and precautions for using fluoroquinolone antibiotics because of the risk of disabling and potentially long-lasting or irreversible side effects.

OR

co-trimoxazole 960mg BD for 14 days then review

IV antibiotics: see the guidance visual summary

For detailed information see the guidance visual summary or https://www.nice.org.uk/guidance/ng110.

NICE

Section last updated September 2024

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Recurrent Urinary Tract Infections

First advise about behavioural and personal hygiene measures, and self-care (with D-mannose or cranberry products) to reduce the risk of UTI.

For postmenopausal women, if no improvement, consider vaginal oestrogen (review within 12 months).

For non-pregnant women, if no improvement, consider single-dose antibiotic prophylaxis for exposure to a trigger (review within 6 months).

For non-pregnant women (if no improvement or no identifiable trigger) or with specialist advice for pregnant women, men, children, or young people, consider a trial of daily antibiotic prophylaxis (review within 6 months).

First choice adult antibiotic prophylaxis:

trimethoprim (avoid in pregnancy) 200mg single dose when exposed to a trigger or 100mg at night

OR

nitrofurantoin (avoid at term) - if eGFR ≥45 ml/minute 100mg single dose when exposed to a trigger or 50 to 100mg at night

Second choice adult antibiotic prophylaxis:

amoxicillin 500mg single dose when exposed to a trigger or 250mg at night

OR

cefalexin 500mg single dose when exposed to a trigger or 125mg at night

For information on children’s dosage or for detailed information see the guidance visual summary or https://www.nice.org.uk/guidance/ng112

NICE

For detailed information click on the visual summary. See also the NICE guideline on urinary tract infection in under 16s: diagnosis and management and the UK Health Security Agency urinary tract infection: diagnostic tools for primary care.

Section last updated Oct 2018

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Catheter-Associated Urinary Tract Infection

Antibiotic treatment is not routinely needed for asymptomatic bacteriuria in people with a urinary catheter.

Consider removing or, if not possible, changing the catheter if it has been in place for more than 7 days. But do not delay antibiotic treatment.

Advise paracetamol for pain.

Advise drinking enough fluids to avoid dehydration.

Offer an antibiotic for a symptomatic infection. When prescribing antibiotics, take account of severity of symptoms, risk of complications, previous urine culture and susceptibility results, previous antibiotic use which may have led to resistant bacteria and local antimicrobial resistance data.

Do not routinely offer antibiotic prophylaxis to people with a short-term or long-term catheter.

Non-pregnant women and men first choice if no upper UTI symptoms:

nitrofurantoin (if eGFR ≥45 ml/minute) 100mg m/r BD (or if unavailable 50mg QDS) for 7 days

OR

trimethoprim (if low risk of resistance) 200mg BD for 7 days

OR

amoxicillin (only if culture results available and susceptible) 500mg TDS for 7 days

Non-pregnant women and men second choice if no upper UTI symptoms:

pivmecillinam (a penicillin) 400mg initial dose, then 200mg TDS for 7 days

Non-pregnant women and men first choice if upper UTI symptoms:

cefalexin 500mg BD or TDS (up to 1g to 1.5g TDS or QDS for severe infections) for 7 to 10 days

OR

co-amoxiclav (only if culture results available and susceptible) 500/125mg TDS for 7 to 10 days

OR

trimethoprim (only if culture results available and susceptible) 200mg BD for 14 days

OR

ciprofloxacin (only if other first-choice antibiotics are unsuitable) 500mg BD for 7 days  

See the MHRA January 2024 advice for restrictions and precautions on using fluoroquinolone antibiotics because of the risk of disabling and potentially long-lasting or irreversible side effects. Fluoroquinolones must now only be prescribed when other commonly recommended antibiotics are inappropriate.

Non-pregnant women and men IV antibiotics:

see the guidance visual summary

Pregnant women first choice:

cefalexin 500mg BD or TDS (up to 1g to 1.5g TDS or QDS for severe infections) for 7 to 10 days

Pregnant women second choice or IV antibiotics:

see the guidance visual summary

Children and young people (3 months and over) first choice:

trimethoprim (if low risk of resistance)

OR

amoxicillin (only if culture results available and susceptible)

OR

cefalexin

OR

co-amoxiclav (only if culture results available and susceptible)

Children and young people (3 months and over) IV antibiotics:

see the guidance visual summary

For information on children’s dosage or for detailed information see the guidance visual summary or https://www.nice.org.uk/guidance/ng113

NICE

See also the UK Health Security Agency urinary tract infection: diagnostic tools for primary care.

Section last updated September 2024

Gastrointestinal Tract Infection text summaries

Please refer to the user guide and principles of treatment when using the antimicrobial prescribing guidance summaries.

Contents

Clostridioides difficile infection

For suspected or confirmed C. difficile infection, see UK Health Security Agency’s guidance on diagnosis and reporting.

Assess: whether it is a first or further episode, severity of infection, individual risk factors for complications or recurrence (such as age, frailty, or comorbidities).

Existing antibiotics: review and stop unless essential. If still essential, consider changing to one with a lower risk of C. difficile infection.

Review the need to continue: proton pump inhibitors, other medicines with gastrointestinal activity or adverse effects (such as laxatives), medicines that may cause problems if people are dehydrated (such as NSAIDs).

Do not offer antimotility medicines such as loperamide.

Offer an oral antibiotic to treat suspected or confirmed C. difficile infection.

For adults, consider seeking prompt specialist advice from a microbiologist or infectious diseases specialist before starting treatment.

For children and young people, treatment should be started by, or after advice from, a microbiologist, paediatric infectious diseases specialist or paediatric gastroenterologist.

If antibiotics have been started for suspected C. difficile infection, and subsequent stool sample tests do not confirm infection, consider stopping these antibiotics.

Adult first-line for first episode of mild, moderate, or severe: 

vancomycin 125mg QDS for 10 days

Adult second-line for first episode of mild, moderate, or severe if vancomycin ineffective: 

fidaxomicin 200mg BD for 10 days

For further episode in an adult within 12 weeks of symptom resolution (relapse): 

fidaxomicin 200mg BD for 10 days

For further episode in an adult more than 12 weeks after symptom resolution (recurrence): 

vancomycin 125mg QDS for 10 days

OR

fidaxomicin 200mg BD for 10 days

For alternative antibiotics if first- and second-line antibiotics are ineffective or for life-threatening infection: seek specialist advice (see the guidance visual summary)

For information on children’s dosage or for detailed information see the guidance visual summary or https://www.nice.org.uk/guidance/ng199

NICE

Section last updated July 2021

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Acute Diverticulitis

Acute diverticulitis and systemically well: Consider no antibiotics, offer simple analgesia (for example paracetamol), advise to re-present if symptoms persist or worsen.

Acute diverticulitis and systemically unwell, immunosuppressed, or significant comorbidity: offer an antibiotic.

Give oral antibiotics if person not referred to hospital for suspected complicated acute diverticulitis.

Give IV antibiotics if admitted to hospital with suspected or confirmed complicated acute diverticulitis (including diverticular abscess).

If CT-confirmed uncomplicated acute diverticulitis, review the need for antibiotics.

First-choice for adults (uncomplicated acute diverticulitis): 

co-amoxiclav 500/125mg TDS for 5 days (a longer course may be needed based on clinical assessment)

Penicillin allergy for adults or if co-amoxiclav unsuitable: 

cefalexin (caution in penicillin allergy) 500mg BD or TDS (up to 1g to 1.5g TDS or QDS for severe infections) AND  metronidazole 400mg TDS for 5 days (a longer course may be needed based on clinical assessment)

OR

trimethoprim 200mg BD WITH metronidazole 400mg TDS for 5 days (a longer course may be needed based on clinical assessment)

OR

Ciprofloxacin (only if switching from IV ciprofloxacin with specialist advice) 500mg BD WITH metronidazole 400mg TDS for 5 days (a longer course may be needed based on clinical assessment)

See the MHRA January 2024 advice for restrictions and precautions on using fluoroquinolone antibiotics because of the risk of disabling and potentially long-lasting or irreversible side effects. Fluoroquinolones must now only be prescribed when other commonly recommended antibiotics are inappropriate

For IV antibiotics in complicated acute diverticulitis (including diverticular abscess): see visual summary or NICE guidance

For information on children’s dosage or for detailed information see the guidance visual summary or https://www.nice.org.uk/guidance/NG147

NICE

Section last updated September 2024

Skin Infection text summaries

Please refer to the user guide and principles of treatment when using the antimicrobial prescribing guidance summaries.

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