Community-acquired pneumonia in adults (non COVID-19)

Overview 
Theory 
Diagnosis 
Management 
Follow up 
Resources 

Please note that formulations/routes and doses may differ between drug names and brands, drug formularies, or locations. Treatment recommendations are specific to patient groups: see disclaimer

INITIAL

suspected CAP: presenting in hospital with life-threatening illness

1st line – empirical intravenous antibiotic therapy

Back

1st line –

empirical intravenous antibiotic therapy

Give empirical antibiotics to patients presenting in hospital with life-threatening disease based on a presumptive clinical diagnosis of CAP.

Immediately order a chest x-ray to confirm the diagnosis.[1][65]

Once a diagnosis of CAP is confirmed, manage these patients as per the protocols below for patients with confirmed CAP on chest x-ray: presenting in hospital.

Practical tip

Think ' Could this be sepsis?' based on acute deterioration in an adult patient in whom there is clinical evidence or strong suspicion of infection.[66][67][68] See Sepsis in adults.

The patient may present with non-specific or non-localised symptoms (e.g., acutely unwell with a normal temperature) or there may be severe signs with evidence of multi-organ dysfunction and shock.[66][67][68]
Remember that sepsis represents the severe, life-threatening end of infection.[79]
Pneumonia is one of the main sources of sepsis.[80]

Use a systematic approach (e.g., National Early Warning Score 2 [NEWS2]), alongside your clinical judgement, to assess the risk of deterioration due to sepsis.[66][68][69][81] Consult local guidelines for the recommended approach at your institution.

Arrange urgent review by a senior clinical decision-maker (e.g., ST4 level doctor in the UK) if you suspect sepsis:[70]

Within 30 minutes for a patient who is critically ill (e.g., NEWS2 score of 7 or more, evidence of septic shock, or other significant clinical concerns).
Within 1 hour for a patient who is severely ill (e.g., NEWS2 score of 5 or 6).

Follow your local protocol for investigation and treatment of all patients with suspected sepsis, or those at risk. Start treatment promptly. Determine urgency of treatment according to likelihood of infection and severity of illness, or according to your local protocol.[70][81]

In the community: refer for emergency medical care in hospital (usually by blue-light ambulance in the UK) any patient who is acutely ill with a suspected infection and is:[67]

Deemed to be at high risk of deterioration due to organ dysfunction (as measured by risk stratification)
At risk of neutropenic sepsis.

Plus – supportive care

Back

Plus –

supportive care

Treatment recommended for ALL patients in selected patient group

Provide supportive care, which may include the following measures.[1][65]

Oxygen

Prescribe oxygen if oxygen saturation <94% and maintain at target range.[1][65] For patients at risk of CO ₂ retention prescribe oxygen if oxygen saturation <88%.[71]

Monitor controlled oxygen therapy. An upper SpO ₂ limit of 96% is reasonable when administering supplemental oxygen to most patients with acute illness who are not at risk of hypercapnia.

Evidence suggests that liberal use of supplemental oxygen (target SpO ₂ >96%) in acutely ill adults is associated with higher mortality than more conservative oxygen therapy.[72]
A lower target SpO ₂ of 88% to 92% is appropriate if the patient is at risk of hypercapnic respiratory failure.[71]

Evidence: Target oxygen saturation in acutely ill adults

Too much supplemental oxygen increases mortality.

Evidence from a large systematic review and meta-analysis supports conservative/controlled oxygen therapy versus liberal oxygen therapy in acutely ill adults who are not at risk of hypercapnia.

Guidelines differ in their recommendations on target oxygen saturation in acutely unwell adults who are receiving supplemental oxygen.
- The 2017 British Thoracic Society (BTS) guideline recommends a target SpO ₂ range of 94% to 98% for patients not at risk of hypercapnia, whereas the 2022 Thoracic Society of Australia and New Zealand (TSANZ) guideline recommends 92% to 96%.[71][130]
- The 2022 Global Initiative for Asthma (GINA) guidelines recommend a target SpO ₂ range of 93% to 96% in the context of acute asthma exacerbations.[131]
A systematic review including a meta-analysis of data from 25 randomised controlled trials, published in 2018 found that in adults with acute illness, liberal oxygen therapy (broadly equivalent to a target saturation >96%) is associated with higher mortality than conservative oxygen therapy (broadly equivalent to a target saturation ≤96%).[72] In-hospital mortality was 11 per 1000 higher for the liberal oxygen therapy group versus the conservative therapy group (95% CI, 2 to 22 per 1000 more). Mortality at 30 days was also higher in the group who had received liberal oxygen (RR 1.14, 95% CI 1.01 to 1.29). The trials included adults with sepsis, critical illness, stroke, trauma, myocardial infarction, cardiac arrest, and patients who had emergency surgery. Studies that were limited to people with chronic respiratory illness or psychiatric illness, or patients on extracorporeal life support, receiving hyperbaric oxygen therapy, or having elective surgery, were all excluded from the review.
An upper SpO ₂ limit of 96% is therefore reasonable when administering supplemental oxygen to patients with acute illness who are not at risk of hypercapnia. However, a higher target may be appropriate for some specific conditions (e.g., pneumothorax, carbon monoxide poisoning, cluster headache, and sickle cell crisis).[132]
In 2019 the BTS reviewed its guidance in response to this systematic review and meta-analysis and decided an interim update was not required.[113]
- The committee noted that the systematic review supported the use of controlled oxygen therapy to a target.
- While the systematic review showed an association between higher oxygen saturations and higher mortality, the BTS committee felt the review was not definitive on what the optimal target range should be. The suggested range of 94% to 96% in the review was based on the lower 95% confidence interval and the median baseline SpO ₂ from the liberal oxygen groups, along with the earlier 2015 TSANZ guideline recommendation.
Subsequently, experience during the COVID-19 pandemic has also made clinicians more aware of the feasibility of permissive hypoxaemia.[133]
Management of oxygen therapy in patients in intensive care is specialised and informed by further evidence that is more specific to this setting.[134][135][136]

Measure arterial blood gases in those with SpO ₂ <94%, those with a risk of hypercapnic ventilatory failure (CO ₂ retention), and all patients with high-severity CAP.[1][65]

Practical tip

Always record the inspired oxygen concentration clearly as this is essential for interpreting blood gas results.

Fluid resuscitation

Assess all patients for volume depletion and give intravenous fluids if required.[1][65]

Standard intensive care unit (ICU) supportive care

Arrange for patients with an indication for ICU admission to be transferred to ICU and managed by ICU specialists together with respiratory physicians.[1][65]

Patients with respiratory failure despite appropriate oxygen therapy require urgent airway management and possible intubation.
Do not routinely give non-invasive ventilation (NIV) or continuous positive airways pressure (CPAP) support in patients with respiratory failure due to CAP.[1][65]
- If indicated, you should conduct a trial of non-invasive support only in a critical care area where immediate expertise is available to allow a rapid transition to invasive ventilation.[1][65]

Vasopressors

Start vasopressors if the patient is hypotensive during or after fluid resuscitation to maintain mean arterial pressure level greater than or equal to 65 mmHg.[137] See Sepsis in adults.

Analgesia

Give simple analgesia as appropriate (e.g., for pleuritic pain).[1][65]

Primary options

paracetamol: oral: 500-1000 mg orally every 4-6 hours when required, maximum 4000 mg/day; intravenous (<51 kg body weight): 15 mg/kg intravenously every 4-6 hours when required, maximum 60 mg/kg/day; intravenous (≥51 kg body weight): 1000 mg intravenously every 4-6 hours when required, maximum 4000 mg/day (3000 mg/day if risk factors for hepatotoxicity)

suspected CAP: presenting in hospital without life-threatening illness

1st line – supportive care while confirming diagnosis

Back

1st line –

supportive care while confirming diagnosis

Confirm diagnosis by chest x-ray before starting antibiotic therapy.

In patients presenting in hospital without life-threatening illness, confirm the diagnosis by chest x-ray before starting antibiotics.[1][65] Once diagnosis is confirmed, patients are managed as per the protocols below for patients with confirmed CAP on chest x-ray: presenting in hospital.

In the meantime, provide supportive care as necessary, which may include the following measures.[1][65]

Oxygen

Prescribe oxygen if oxygen saturation <94% and maintain at target range.[1][65] For patients at risk of hypercapnia prescribe oxygen if oxygen saturation <88%.[71]

Monitor controlled oxygen therapy. An upper SpO ₂ limit of 96% is reasonable when administering supplemental oxygen to most patients with acute illness who are not at risk of hypercapnia.

Evidence suggests that liberal use of supplemental oxygen (target SpO ₂ >96%) in acutely ill adults is associated with higher mortality than more conservative oxygen therapy.[72]
A lower target SpO ₂ of 88% to 92% is appropriate if the patient is at risk of hypercapnic respiratory failure.[71]

Evidence: Target oxygen saturation in acutely ill adults

Too much supplemental oxygen increases mortality.

Evidence from a large systematic review and meta-analysis supports conservative/controlled oxygen therapy versus liberal oxygen therapy in acutely ill adults who are not at risk of hypercapnia.

Guidelines differ in their recommendations on target oxygen saturation in acutely unwell adults who are receiving supplemental oxygen.
- The 2017 British Thoracic Society (BTS) guideline recommends a target SpO ₂ range of 94% to 98% for patients not at risk of hypercapnia, whereas the 2022 Thoracic Society of Australia and New Zealand (TSANZ) guideline recommends 92% to 96%.[71][130]
- The 2022 Global Initiative for Asthma (GINA) guidelines recommend a target SpO ₂ range of 93% to 96% in the context of acute asthma exacerbations.[131]
A systematic review including a meta-analysis of data from 25 randomised controlled trials, published in 2018 found that in adults with acute illness, liberal oxygen therapy (broadly equivalent to a target saturation >96%) is associated with higher mortality than conservative oxygen therapy (broadly equivalent to a target saturation ≤96%).[72] In-hospital mortality was 11 per 1000 higher for the liberal oxygen therapy group versus the conservative therapy group (95% CI, 2 to 22 per 1000 more). Mortality at 30 days was also higher in the group who had received liberal oxygen (RR 1.14, 95% CI 1.01 to 1.29). The trials included adults with sepsis, critical illness, stroke, trauma, myocardial infarction, cardiac arrest, and patients who had emergency surgery. Studies that were limited to people with chronic respiratory illness or psychiatric illness, or patients on extracorporeal life support, receiving hyperbaric oxygen therapy, or having elective surgery, were all excluded from the review.
An upper SpO ₂ limit of 96% is therefore reasonable when administering supplemental oxygen to patients with acute illness who are not at risk of hypercapnia. However, a higher target may be appropriate for some specific conditions (e.g., pneumothorax, carbon monoxide poisoning, cluster headache, and sickle cell crisis).[132]
In 2019 the BTS reviewed its guidance in response to this systematic review and meta-analysis and decided an interim update was not required.[113]
- The committee noted that the systematic review supported the use of controlled oxygen therapy to a target.
- While the systematic review showed an association between higher oxygen saturations and higher mortality, the BTS committee felt the review was not definitive on what the optimal target range should be. The suggested range of 94% to 96% in the review was based on the lower 95% confidence interval and the median baseline SpO ₂ from the liberal oxygen groups, along with the earlier 2015 TSANZ guideline recommendation.
Subsequently, experience during the COVID-19 pandemic has also made clinicians more aware of the feasibility of permissive hypoxaemia.[133]
Management of oxygen therapy in patients in intensive care is specialised and informed by further evidence that is more specific to this setting.[134][135][136]

Measure arterial blood gases in those with SpO ₂ <94%, those with a risk of hypercapnic ventilatory failure (CO ₂ retention), and all patients with high-severity CAP.[1][65]

Practical tip

Always record the inspired oxygen concentration clearly as this is essential for interpreting blood gas results.

Fluid resuscitation

Assess all patients for volume depletion and give intravenous fluids if required.[1][65]

Standard intensive care unit (ICU) supportive care

Arrange for patients with an indication for ICU admission to be transferred to ICU and managed by ICU specialists together with respiratory physicians.[1][65]

Patients with respiratory failure despite appropriate oxygen therapy require urgent airway management and possible intubation.
Do not routinely give non-invasive ventilation (NIV) or continuous positive airways pressure (CPAP) support in patients with respiratory failure due to CAP.[1][65]
- If indicated, you should conduct a trial of non-invasive support only in a critical care area where immediate expertise is available to allow a rapid transition to invasive ventilation.[1][65]

Vasopressors

Start vasopressors if the patient is hypotensive during or after fluid resuscitation to maintain mean arterial pressure level greater than or equal to 65 mmHg.[137] See our Sepsis in adults topic for more information.

Analgesia

Give simple analgesia as appropriate (e.g., for pleuritic pain).[1][65]

Primary options

suspected CAP: presenting in the community

high-severity (CRB-65 = 3 or 4)

1st line – urgent hospital admission

Consider – empirical antibiotic prior to hospital transfer

Back

Consider –

empirical antibiotic prior to hospital transfer

Additional treatment recommended for SOME patients in selected patient group

Give empirical antibiotics prior to hospital transfer (usually by blue-light ambulance in the UK) to any patients with suspected high-severity CAP considered to be life-threatening, according to your local protocol.[1][65]

British Thoracic Society guidelines recommend intravenous benzylpenicillin or oral amoxicillin. Oral clarithromycin is an alternative for people who are allergic to penicillin.[1][65]

Consider giving empirical antibiotics prior to hospital transfer to patients with suspected high-severity CAP where there are likely to be delays of over 6 hours to hospital admission and treatment.[1][65]

Pre-admission antibiotics can negatively influence the results of subsequent microbiological investigations, but this is not seen as a reason for withholding antibiotics if a general practitioner considers it indicated.[1]

Consult your local protocol for guidance on selection of antibiotic regimen.

moderate-severity (CRB-65 = 1 or 2)

1st line – hospital referral

Back

1st line –

hospital referral

Refer patients presenting in the community with moderate-severity CAP (CRB-65 score of 1 or 2) to hospital for assessment and management.These patients are at increased risk of death, particularly those with a score of 2.[1][63][65]

In hospital, once the diagnosis of CAP is confirmed by chest x-ray and the disease severity has been assessed, patients are managed as per the protocols below for patients with confirmed CAP on chest x-ray: presenting in hospital.

Consider managing patients in the community if they prefer to be treated at home and they meet the following criteria:[1][63][65]

They are able to take oral medication safely and reliably
Their social circumstances make them suitable for treatment at home
They do not have unstable comorbidities.

Take a cautious approach, however, when deciding whether it is safe to treat any patient with moderate-severity CAP in the community. You should refer the majority for management in hospital.[1][63][65]

If you decide to treat the patient in the community, follow the same treatment recommendations given below for patients with suspected CAP: presenting in the community (low-severity).

low-severity (CRB-65 = 0)

1st line – empirical oral antibiotic therapy

Back

1st line –

empirical oral antibiotic therapy

Give empirical oral antibiotics and manage people with low-severity CAP (CRB-65 score of 0) in the community.[1][63][65]

The first-line option is amoxicillin.[1][65] Alternative options for patients who are allergic to penicillin are a macrolide (e.g., clarithromycin) or a tetracycline (e.g., doxycycline).[1][65]
If the patient does not respond to amoxicillin monotherapy, consider adding, or switching to, a macrolide (e.g., clarithromycin).[1][65]

Advise patients (and their carers) to seek medical advice if their symptoms worsen rapidly or significantly, their symptoms do not start to improve within 3 days, or they become systemically very unwell.[117]

Admit urgently to hospital any patient on antibiotic treatment with features of moderate- or high-severity infection.[1][65] Around 10% of patients managed in the community do not respond to antibiotic therapy and require hospitalisation.[142]

Give antibiotic treatment for 5 days.[117][125] The National Institute for Health and Care Excellence recommends stopping treatment after 5 days unless microbiological results suggest a longer course or the patient is not clinically stable. This should be based on your clinical judgement and the following criteria:[117][126]

Fever in past 48 hours, or more than one sign of clinical instability:
- Systolic blood pressure <90 mmHg
- Heart rate >100/minute
- Respiratory rate >24/minute
- Arterial oxygen saturation <90% or PaO ₂ <60 mmHg in room air.

Consult local protocols for guidance on selection of antibiotic regimen.

Plus – supportive care

Back

Plus –

supportive care

Treatment recommended for ALL patients in selected patient group

Advise patients to rest, to drink plenty of fluids, and not to smoke.[1][65]

Give simple analgesia as appropriate (e.g., for pleuritic pain).[1][65]

Primary options

Consider – hospital admission

ACUTE

confirmed CAP on chest x-ray: presenting in hospital

high-severity (CURB-65 = 3-5)

1st line – empirical intravenous antibiotic therapy

Back

1st line –

empirical intravenous antibiotic therapy

Always manage patients with high-severity CAP in hospital.[1][65]

Give empirical broad-spectrum intravenous antibiotics immediately after diagnosis. This should be within 4 hours of presentation to hospital.[1][65][117]

Prescribe an appropriate antibiotic regimen according to your local protocol to help reduce the development of antibiotic resistance and Clostridium difficile infection. Consult with a microbiologist. The British Thoracic Society (BTS) recommends:[1][65]

A broad-spectrum beta-lactamase-resistant penicillin (e.g., amoxicillin/clavulanate) plus a macrolide (e.g., clarithromycin).[1][65]
For patients who are allergic to penicillin, give a second-generation cephalosporin (e.g., cefuroxime) or a third-generation cephalosporin (e.g., cefotaxime or ceftriaxone) plus a macrolide (e.g., clarithromycin).[1][65]
A small number of patients are allergic to both penicillins and cephalosporins; consult an infectious disease consultant for selection of appropriate antibiotics in these patients.

Review route of administration initially on the ward round following admission and then daily thereafter.[1][65] De-escalate treatment as soon as appropriate, including switching from intravenous to oral therapy.[1][65] When making this decision consider response to treatment (see practical tip), change in disease severity, and contraindications to oral administration such as:[1]

Patient is unable to swallow (e.g., impaired swallowing reflex, impaired consciousness)
Gastrointestinal malabsorption for functional or anatomical reasons.

Practical tip

Pointers to clinical improvement

The following clinical features should prompt you to consider switching from intravenous to oral antibiotic therapy:[1][65]

Pulse rate <100 beats/minute
Resolution of tachypnoea
Clinically hydrated and taking oral fluids
Resolution of fever for >24 hours
Resolution of hypotension
Absence of hypoxia
Improving white cell count
Non-bacteraemic infection
No microbiological evidence of legionella, staphylococcal, or gram-negative enteric bacilli infection
No concerns over gastrointestinal absorption.

Give antibiotic therapy for 5 days.[117][125] The National Institute for Health and Care Excellence recommends stopping treatment after 5 days unless microbiological results suggest a longer course or the patient is not clinically stable.[117] This should be based on your clinical judgement and the following criteria:[117][126]

Fever in past 48 hours, or more than one sign of clinical instability:
- Systolic blood pressure <90 mmHg
- Heart rate >100/minute
- Respiratory rate >24/minute
- Arterial oxygen saturation <90% or PaO ₂ <60 mmHg in room air.

In some people, longer courses might be needed due to individual circumstances. In the UK, some hospitals require consultation with the microbiology team if considering extending the duration of antibiotic treatment beyond 5 days in high-severity CAP. Follow your local protocol.

Consult your local protocol for guidance on selection of antibiotic regimen.

Consider – fluoroquinolone

Back

Consider –

fluoroquinolone

Additional treatment recommended for SOME patients in selected patient group

Consult with a microbiologist and senior clinician before giving a fluoroquinolone.

Consider safety issues associated with fluoroquinolone use. Fluoroquinolones are known to cause tendonitis, tendon rupture, arthralgia, neuropathies, and other musculoskeletal or nervous system effects.[127][128]

The British Thoracic Society guideline recommends adding a fluoroquinolone to the existing empirical regimen (i.e., triple therapy) if the patient does not respond, or if legionella pneumonia is strongly suspected.[1][65] However, in practice there are concerns about the risk of using a macrolide and a fluoroquinolone together as they can both prolong the QT interval. Therefore, some clinicians may replace the macrolide in the original empirical regimen with a fluoroquinolone instead (i.e., dual therapy).

Plus – supportive care

Back

Plus –

supportive care

Treatment recommended for ALL patients in selected patient group

Provide supportive care, which may include the following measures.[1][65]

Oxygen

Prescribe oxygen if oxygen saturation <94% and maintain at target range.[1][65] For patients at risk of hypercapnia prescribe oxygen if oxygen saturation <88%.[71]

Monitor controlled oxygen therapy. An upper SpO ₂ limit of 96% is reasonable when administering supplemental oxygen to most patients with acute illness who are not at risk of hypercapnia.

Evidence suggests that liberal use of supplemental oxygen (target SpO ₂ >96%) in acutely ill adults is associated with higher mortality than more conservative oxygen therapy.[72]
A lower target SpO ₂ of 88% to 92% is appropriate if the patient is at risk of hypercapnic respiratory failure.[71]

Evidence: Target oxygen saturation in acutely ill adults

Too much supplemental oxygen increases mortality.

Evidence from a large systematic review and meta-analysis supports conservative/controlled oxygen therapy versus liberal oxygen therapy in acutely ill adults who are not at risk of hypercapnia.

Guidelines differ in their recommendations on target oxygen saturation in acutely unwell adults who are receiving supplemental oxygen.
- The 2017 British Thoracic Society (BTS) guideline recommends a target SpO ₂ range of 94% to 98% for patients not at risk of hypercapnia, whereas the 2022 Thoracic Society of Australia and New Zealand (TSANZ) guideline recommends 92% to 96%.[71][130]
- The 2022 Global Initiative for Asthma (GINA) guidelines recommend a target SpO ₂ range of 93% to 96% in the context of acute asthma exacerbations.[131]
A systematic review including a meta-analysis of data from 25 randomised controlled trials, published in 2018 found that in adults with acute illness, liberal oxygen therapy (broadly equivalent to a target saturation >96%) is associated with higher mortality than conservative oxygen therapy (broadly equivalent to a target saturation ≤96%).[72] In-hospital mortality was 11 per 1000 higher for the liberal oxygen therapy group versus the conservative therapy group (95% CI, 2 to 22 per 1000 more). Mortality at 30 days was also higher in the group who had received liberal oxygen (RR 1.14, 95% CI 1.01 to 1.29). The trials included adults with sepsis, critical illness, stroke, trauma, myocardial infarction, cardiac arrest, and patients who had emergency surgery. Studies that were limited to people with chronic respiratory illness or psychiatric illness, or patients on extracorporeal life support, receiving hyperbaric oxygen therapy, or having elective surgery, were all excluded from the review.
An upper SpO ₂ limit of 96% is therefore reasonable when administering supplemental oxygen to patients with acute illness who are not at risk of hypercapnia. However, a higher target may be appropriate for some specific conditions (e.g., pneumothorax, carbon monoxide poisoning, cluster headache, and sickle cell crisis).[132]
In 2019 the BTS reviewed its guidance in response to this systematic review and meta-analysis and decided an interim update was not required.[113]
- The committee noted that the systematic review supported the use of controlled oxygen therapy to a target.
- While the systematic review showed an association between higher oxygen saturations and higher mortality, the BTS committee felt the review was not definitive on what the optimal target range should be. The suggested range of 94% to 96% in the review was based on the lower 95% confidence interval and the median baseline SpO ₂ from the liberal oxygen groups, along with the earlier 2015 TSANZ guideline recommendation.
Subsequently, experience during the COVID-19 pandemic has also made clinicians more aware of the feasibility of permissive hypoxaemia.[133]
Management of oxygen therapy in patients in intensive care is specialised and informed by further evidence that is more specific to this setting.[134][135][136]

Measure arterial blood gases in those with SpO ₂ <94%, those with a risk of hypercapnic ventilatory failure (CO ₂ retention), and all patients with high-severity CAP.[1][65]

Fluid resuscitation

Assess all patients for volume depletion and give intravenous fluids if required.[1][65]

Standard intensive care unit (ICU) supportive care

Arrange for patients with CURB-65 scores of 4 and 5 and an indication for ICU admission to be transferred to ICU and managed by ICU specialists together with respiratory physicians.[1][65]

Patients with respiratory failure despite appropriate oxygen therapy require urgent airway management and possible intubation.
Do not routinely give non-invasive ventilation (NIV) or continuous positive airways pressure (CPAP) support in patients with respiratory failure due to CAP.[1][65]
- If indicated, you should conduct a trial of non-invasive support only in a critical care area where immediate expertise is available to allow a rapid transition to invasive ventilation.[1][65]

Vasopressors

Start vasopressors if the patient is hypotensive during or after fluid resuscitation to maintain mean arterial pressure level greater than or equal to 65 mmHg.[137]

Venous thromboembolism (VTE) prophylaxis

Consider prophylaxis for VTE with a low molecular weight heparin for all patients who are not fully mobile.[1][65] In practice in the UK, prescription of heparin will be prompted if appropriate once you have recorded your VTE risk assessment in the patient’s electronic record.

Nutritional support

Arrange nutritional support (whether enteral, parenteral, or via nasogastric feeding) for patients with severe CAP who require a prolonged hospital stay.[1][65]

Airway clearance

Do not treat people with uncomplicated pneumonia with traditional airway clearance techniques routinely. If needed, offer these patients advice regarding expectoration of sputum.[1][65]
Consider airway clearance techniques if the patient has difficulty expectorating sputum or if they have a pre-existing lung condition.[1][65]

Analgesia

Give simple analgesia as appropriate (e.g., for pleuritic pain).[1]

Primary options

Consider – switch to pathogen-targeted antibiotic therapy

Back

Consider –

switch to pathogen-targeted antibiotic therapy

Additional treatment recommended for SOME patients in selected patient group

Consult with a microbiologist about appropriate pathogen-targeted antibiotic therapy.[1][65]

Switch from empirical antibiotics to pathogen-targeted antibiotics as soon as specific pathogens are identified (unless there are legitimate concerns about dual-pathogen infection).[1][65]

Only about one third to one quarter of patients with CAP admitted to hospital will have their pneumonia defined microbiologically.[1] Among these patients:

Around 14% have an atypical pathogen, of which:[21]
- 7% have Mycoplasma pneumoniae
- 4% have Chlamydophila pneumoniae
- 3% have Legionella pneumophila.
Those with infections due to Mycoplasma, Chlamydophila, and Coxiella burnetii will be diagnosed late in the illness on the basis of seroconversion, reducing the opportunity for early targeted therapy.[1]

Consider switching the choice of agent once the results of sensitivity testing are available or following consultation with a microbiologist, intensivist, or respiratory physician.[1][65]

BTS recommendations for pathogen-targeted antibiotics[1][65]

Pathogen	Preferred antibiotic	Alternative antibiotic
Mycoplasma pneumoniae Chlamydophila pneumoniae	Clarithromycin (orally or intravenously)	Doxycycline (orally) or a fluoroquinolone (orally or intravenously)
Legionella species	Fluoroquinolone (orally or intravenously)	Clarithromycin (orally or intravenously) or azithromycin (in countries where it is used for managing pneumonia)
Streptococcus pneumoniae	Amoxicillin (orally) or benzylpenicillin (intravenously)	Clarithromycin (orally) or cefuroxime or cefotaxime or ceftriaxone (intravenously)
Chlamydia psittaci Coxiella burnetii	Doxycycline (orally)	Clarithromycin (orally or intravenously)
Haemophilus influenzae	Non-beta-lactamase-producing: amoxicillin (orally or intravenously) Beta-lactamase-producing: amoxicillin/clavulanate (orally or intravenously)	Cefuroxime or cefotaxime or ceftriaxone (intravenously) or a fluoroquinolone (orally or intravenously)
Gram-negative enteric bacilli	Cefuroxime or cefotaxime or ceftriaxone (intravenously)	Fluoroquinolone (intravenously) or imipenem/cilastatin (intravenously) or meropenem (intravenously)
Pseudomonas aeruginosa	Ceftazidime (intravenously) plus Gentamicin or tobramycin (dose monitoring required)	Ciprofloxacin (intravenously) or piperacillin/tazobactam (intravenously) plus Gentamicin or tobramycin (dose monitoring required)
Staphylococcus aureus: non-MRSA	Flucloxacillin (intravenously) with or without Rifampicin (orally or intravenously)
Staphylococcus aureus: MRSA	Vancomycin (intravenously; dose monitoring required) or linezolid (intravenously) or teicoplanin (intravenously) with or without Rifampicin (orally or intravenously)

moderate-severity (CURB-65 = 2)

1st line – empirical oral or intravenous antibiotic therapy

Back

1st line –

empirical oral or intravenous antibiotic therapy

Consider patients with moderate-severity CAP for short-stay inpatient treatment or hospital-supervised outpatient treatment.[1][65]

Give antibiotics as soon as possible after diagnosis. This should be within 4 hours of presentation to hospital.[1][65][117]

Give broad-spectrum empirical oral antibiotics.

Most patients with moderate-severity CAP can be treated with dual oral antibiotic therapy.[1][65] British Thoracic Society guidelines recommend amoxicillin plus a macrolide (e.g., clarithromycin).[1][65]
For patients who are allergic to penicillin or macrolides, consider oral doxycycline.[1][65] Alternative choices include oral levofloxacin or moxifloxacin (after considering safety issues associated with fluoroquinolone use).[1][65]
If oral antibiotics are contraindicated (e.g., patient is unable to swallow or has gastrointestinal malabsorption for functional or anatomical reasons) give intravenous amoxicillin or benzylpenicillin plus clarithromycin.[1][65]
For patients who are allergic to penicillin in whom oral antibiotics are contraindicated, give a second-generation cephalosporin (e.g., cefuroxime) or a third-generation cephalosporin (e.g., cefotaxime or ceftriaxone) plus clarithromycin, or intravenous levofloxacin monotherapy.[1][65]
If the patient does not respond to a combination of amoxicillin and clarithromycin, consider changing treatment to doxycycline or a fluoroquinolone with effective pneumococcal cover (e.g., levofloxacin, moxifloxacin).[1][65]

More info: EMA and MHRA restrictions on the use of fluoroquinolone antibiotics

In November 2018, the European Medicines Agency (EMA) completed a review of serious, disabling, and potentially irreversible adverse effects associated with systemic and inhaled fluoroquinolone antibiotics. These adverse effects include tendonitis, tendon rupture, arthralgia, neuropathies, and other musculoskeletal or nervous system effects.

As a consequence of this review, the EMA now recommends that fluoroquinolone antibiotics be restricted for use in serious, life-threatening bacterial infections only. Furthermore, they recommend that fluoroquinolones should not be used for mild to moderate infections unless other appropriate antibiotics for the specific infection cannot be used, and should not be used in non-severe, non-bacterial, or self-limiting infections. Patients who are older, have renal impairment, or have had a solid organ transplant, and those being treated with a corticosteroid are at a higher risk of tendon damage. Co-administration of a fluoroquinolone and a corticosteroid should be avoided.[127] The UK-based Medicines and Healthcare products Regulatory Agency (MHRA) supports these recommendations.[128]
For this reason, fluoroquinolones (e.g., levofloxacin, moxifloxacin) should only be considered in moderate-severity CAP when it is considered inappropriate to use other antibiotics that are commonly recommended for the treatment of CAP. Consult with a microbiologist about whether a fluoroquinolone is an appropriate option for your patient.

Consider monotherapy with a macrolide for patients who have been treated in the community and who have not responded to an adequate course of amoxicillin prior to hospital admission.[1][65]

Deciding whether the course of amoxicillin was adequate is tricky and involves clinical judgement. Consult a senior clinician before prescribing monotherapy within the first 24 hours of admission.[1][65]

Review the need for intravenous antibiotics initially on the ward round following admission and then every day thereafter.[1][65]

NICE guidelines on antimicrobial prescribing in adults recommend reviewing intravenous antibiotics by 48 hours, and considering switching to oral treatment if possible.[117] Best practice is to review intravenous antibiotics every day; most intravenous antibiotics can be stopped and switched to oral treatment within 24 hours.

Switch to oral antibiotics as soon as clinical improvement occurs (see practical tip), and as long as there are no contraindications to oral administration (e.g., patient is unable to swallow or has gastrointestinal malabsorption for functional or anatomical reasons).[1][65]

Practical tip

Pointers to clinical improvement

The following clinical features should prompt you to consider switching from intravenous to oral antibiotic therapy:[1][65]

Pulse rate <100 beats/minute
Resolution of tachypnoea
Clinically hydrated and taking oral fluids
Resolution of fever for >24 hours
Resolution of hypotension
Absence of hypoxia
Improving white cell count
Non-bacteraemic infection
No microbiological evidence of legionella, staphylococcal, or gram-negative enteric bacilli infection
No concerns over gastrointestinal absorption.

Give antibiotic therapy for 5 days.[117][125] The National Institute for Health and Care Excellence recommends stopping treatment after 5 days unless microbiological results suggest a longer course or the patient is not clinically stable.[117] This should be based on your clinical judgement and the following criteria:[117][126]

Fever in past 48 hours, or more than one sign of clinical instability:
- Systolic blood pressure <90 mmHg
- Heart rate >100/minute
- Respiratory rate >24/minute
- Arterial oxygen saturation <90% or PaO ₂ <60 mmHg in room air.

Consult your local protocol for guidance on selection of antibiotic regimen.

Plus – supportive care

Back

Plus –

supportive care

Treatment recommended for ALL patients in selected patient group

Provide supportive care, which may include the following measures.[1][65]

Oxygen

Prescribe oxygen if oxygen saturation <94% and maintain at target range.[1][65] For patients at risk of hypercapnia prescribe oxygen if oxygen saturation <88%.[71]

Monitor controlled oxygen therapy. An upper SpO ₂ limit of 96% is reasonable when administering supplemental oxygen to most patients with acute illness who are not at risk of hypercapnia.

Evidence suggests that liberal use of supplemental oxygen (target SpO ₂ >96%) in acutely ill adults is associated with higher mortality than more conservative oxygen therapy.[72]
A lower target SpO ₂ of 88% to 92% is appropriate if the patient is at risk of hypercapnic respiratory failure.[71]

Evidence: Target oxygen saturation in acutely ill adults

Too much supplemental oxygen increases mortality.

Evidence from a large systematic review and meta-analysis supports conservative/controlled oxygen therapy versus liberal oxygen therapy in acutely ill adults who are not at risk of hypercapnia.

Guidelines differ in their recommendations on target oxygen saturation in acutely unwell adults who are receiving supplemental oxygen.
- The 2017 British Thoracic Society (BTS) guideline recommends a target SpO ₂ range of 94% to 98% for patients not at risk of hypercapnia, whereas the 2022 Thoracic Society of Australia and New Zealand (TSANZ) guideline recommends 92% to 96%.[71][130]
- The 2022 Global Initiative for Asthma (GINA) guidelines recommend a target SpO ₂ range of 93% to 96% in the context of acute asthma exacerbations.[131]
A systematic review including a meta-analysis of data from 25 randomised controlled trials, published in 2018 found that in adults with acute illness, liberal oxygen therapy (broadly equivalent to a target saturation >96%) is associated with higher mortality than conservative oxygen therapy (broadly equivalent to a target saturation ≤96%).[72] In-hospital mortality was 11 per 1000 higher for the liberal oxygen therapy group versus the conservative therapy group (95% CI, 2 to 22 per 1000 more). Mortality at 30 days was also higher in the group who had received liberal oxygen (RR 1.14, 95% CI 1.01 to 1.29). The trials included adults with sepsis, critical illness, stroke, trauma, myocardial infarction, cardiac arrest, and patients who had emergency surgery. Studies that were limited to people with chronic respiratory illness or psychiatric illness, or patients on extracorporeal life support, receiving hyperbaric oxygen therapy, or having elective surgery, were all excluded from the review.
An upper SpO ₂ limit of 96% is therefore reasonable when administering supplemental oxygen to patients with acute illness who are not at risk of hypercapnia. However, a higher target may be appropriate for some specific conditions (e.g., pneumothorax, carbon monoxide poisoning, cluster headache, and sickle cell crisis).[132]
In 2019 the BTS reviewed its guidance in response to this systematic review and meta-analysis and decided an interim update was not required.[113]
- The committee noted that the systematic review supported the use of controlled oxygen therapy to a target.
- While the systematic review showed an association between higher oxygen saturations and higher mortality, the BTS committee felt the review was not definitive on what the optimal target range should be. The suggested range of 94% to 96% in the review was based on the lower 95% confidence interval and the median baseline SpO ₂ from the liberal oxygen groups, along with the earlier 2015 TSANZ guideline recommendation.
Subsequently, experience during the COVID-19 pandemic has also made clinicians more aware of the feasibility of permissive hypoxaemia.[133]
Management of oxygen therapy in patients in intensive care is specialised and informed by further evidence that is more specific to this setting.[134][135][136]

Measure arterial blood gases in those with SpO ₂ <94%, those with a risk of hypercapnic ventilatory failure (CO ₂ retention), and all patients with high-severity CAP.[1][65]

Fluid resuscitation

Assess all patients for volume depletion and give intravenous fluids if required.[1][65]

Venous thromboembolism (VTE) prophylaxis

Consider prophylaxis for VTE with a low molecular weight heparin for all patients who are not fully mobile.[1][65]

Airway clearance

Do not treat people with uncomplicated pneumonia with traditional airway clearance techniques routinely. If needed, offer these patients advice regarding expectoration of sputum.[1][65]
Consider airway clearance techniques if the patient has difficulty expectorating sputum or if they have a pre-existing lung condition.[1][65]

Analgesia

Give simple analgesia as appropriate (e.g., for pleuritic pain).[1][65]

Primary options

Consider – switch to pathogen-targeted antibiotic therapy

Back

Consider –

switch to pathogen-targeted antibiotic therapy

Additional treatment recommended for SOME patients in selected patient group

Consult with a microbiologist about appropriate pathogen-targeted antibiotic therapy.[1][65]

Switch from empirical antibiotics to pathogen-targeted antibiotics as soon as specific pathogens are identified (unless there are legitimate concerns about dual-pathogen infection).[1][65]

Only about one third to one quarter of patients with CAP admitted to hospital will have their pneumonia defined microbiologically.[1] Among these patients:

Around 14% have an atypical pathogen, of which[21]
- 7% have Mycoplasma pneumoniae
- 4% have Chlamydophila pneumoniae
- 3% have Legionella pneumophila
Those with infections due to Mycoplasma, Chlamydophila, and Coxiella burnetii will be diagnosed late in the illness on the basis of seroconversion, reducing the opportunity for early targeted therapy.[1]

Consider switching the choice of agent once the results of sensitivity testing are available or following consultation with a microbiologist, intensivist, or respiratory physician.[1][65]

BTS recommendations for pathogen-targeted antibiotics[1][65]

Pathogen	Preferred antibiotic	Alternative antibiotic
Mycoplasma pneumoniae Chlamydophila pneumoniae	Clarithromycin (orally or intravenously)	Doxycycline (orally) or a fluoroquinolone (orally or intravenously)
Legionella species	Fluoroquinolone (orally or intravenously)	Clarithromycin (orally or intravenously) or azithromycin (in countries where it is used for managing pneumonia)
Streptococcus pneumoniae	Amoxicillin (orally) or benzylpenicillin (intravenously)	Clarithromycin (orally) or cefuroxime or cefotaxime or ceftriaxone (intravenously)
Chlamydia psittaci Coxiella burnetii	Doxycycline (orally)	Clarithromycin (orally or intravenously)
Haemophilus influenzae	Non-beta-lactamase-producing: amoxicillin (orally or intravenously) Beta-lactamase-producing: amoxicillin/clavulanate (orally or intravenously)	Cefuroxime or cefotaxime or ceftriaxone (intravenously) or a fluoroquinolone (orally or intravenously)
Gram-negative enteric bacilli	Cefuroxime or cefotaxime or ceftriaxone (intravenously)	Fluoroquinolone (intravenously) or imipenem/cilastatin (intravenously) or meropenem (intravenously)
Pseudomonas aeruginosa	Ceftazidime (intravenously) plus Gentamicin or tobramycin (dose monitoring required)	Ciprofloxacin (intravenously) or piperacillin/tazobactam (intravenously) plus Gentamicin or tobramycin (dose monitoring required)
Staphylococcus aureus: non-MRSA	Flucloxacillin (intravenously) with or without Rifampicin (orally or intravenously)
Staphylococcus aureus: MRSA	Vancomycin (intravenously; dose monitoring required) or linezolid (intravenously) or teicoplanin (intravenously) with or without Rifampicin (orally or intravenously)

low-severity (CURB-65 = 0-1)

1st line – empirical oral or intravenous antibiotic therapy

Back

1st line –

empirical oral or intravenous antibiotic therapy

Most patients with low-severity CAP can be discharged for treatment at home. However, consider admitting patients if:[1][63][65]

They are not able to take oral medication safely and reliably
Their social circumstances do not make them suitable for treatment at home
They have unstable comorbidities
They prefer to be treated in hospital.

Give antibiotics as soon as possible. This should be within 4 hours of presentation to hospital.[1][63][65]

Most patients with low-severity CAP managed in hospital can be treated with oral antibiotics.[1][65]

The preferred choice is amoxicillin.[1][65] Consider a macrolide (e.g., clarithromycin) or a tetracycline (e.g., doxycycline) for patients who are allergic to penicillin.[1][65]
If the patient does not respond to amoxicillin monotherapy, consider adding, or switching to, a macrolide (e.g., clarithromycin).[1][65]

If the oral route is contraindicated (e.g., impaired swallowing reflex, impaired consciousness, gastrointestinal malabsorption) consider intravenous amoxicillin, benzylpenicillin, or clarithromycin.[1]

Review the need for intravenous antibiotics initially during the ward round following admission and then every day after.[1]

NICE guidelines on antimicrobial prescribing in adults recommend reviewing intravenous antibiotics by 48 hours, and considering switching to oral treatment if possible.[117] Best practice is to review intravenous antibiotics every day; most intravenous antibiotics can be stopped and switched to oral treatment within 24 hours.

Switch to oral antibiotics as soon as clinical improvement occurs (see practical tip), and as long as there are no contraindications to oral administration.

Practical tip

Pointers to clinical improvement

The following clinical features should prompt you to consider switching from intravenous to oral antibiotic therapy:[1][65]

Pulse rate <100 beats/minute
Resolution of tachypnoea
Clinically hydrated and taking oral fluids
Resolution of fever for >24 hours
Resolution of hypotension
Absence of hypoxia
Improving white cell count
Non-bacteraemic infection
No microbiological evidence of legionella, staphylococcal, or gram-negative enteric bacilli infection
No concerns over gastrointestinal absorption.

Give antibiotic therapy for 5 days.[117][125] The National Institute for Health and Care Excellence recommends stopping treatment after 5 days unless microbiological results suggest a longer course or the patient is not clinically stable.[117] This should be based on your clinical judgement and the following criteria:[117][126]

Fever in past 48 hours, or more than one sign of clinical instability:
- Systolic blood pressure <90 mmHg
- Heart rate >100/minute
- Respiratory rate >24/minute
- Arterial oxygen saturation <90% or PaO ₂ <60 mmHg in room air.

Consult local protocols for guidance on selection of antibiotic regimen.

Plus – supportive care

Back

Plus –

supportive care

Treatment recommended for ALL patients in selected patient group

Provide supportive care, which may include the following measures.[1][65]

Oxygen

Prescribe oxygen if oxygen saturation <94% and maintain at target range.[1][65] For patients at risk of hypercapnia prescribe oxygen if oxygen saturation <88%.[71]

Monitor controlled oxygen therapy. An upper SpO ₂ limit of 96% is reasonable when administering supplemental oxygen to most patients with acute illness who are not at risk of hypercapnia.

Evidence suggests that liberal use of supplemental oxygen (target SpO ₂ >96%) in acutely ill adults is associated with higher mortality than more conservative oxygen therapy.[72]
A lower target SpO ₂ of 88% to 92% is appropriate if the patient is at risk of hypercapnic respiratory failure.[71]

Evidence: Target oxygen saturation in acutely ill adults

Too much supplemental oxygen increases mortality.

Evidence from a large systematic review and meta-analysis supports conservative/controlled oxygen therapy versus liberal oxygen therapy in acutely ill adults who are not at risk of hypercapnia.

Guidelines differ in their recommendations on target oxygen saturation in acutely unwell adults who are receiving supplemental oxygen.
- The 2017 British Thoracic Society (BTS) guideline recommends a target SpO ₂ range of 94% to 98% for patients not at risk of hypercapnia, whereas the 2022 Thoracic Society of Australia and New Zealand (TSANZ) guideline recommends 92% to 96%.[71][130]
- The 2022 Global Initiative for Asthma (GINA) guidelines recommend a target SpO ₂ range of 93% to 96% in the context of acute asthma exacerbations.[131]
A systematic review including a meta-analysis of data from 25 randomised controlled trials, published in 2018 found that in adults with acute illness, liberal oxygen therapy (broadly equivalent to a target saturation >96%) is associated with higher mortality than conservative oxygen therapy (broadly equivalent to a target saturation ≤96%).[72] In-hospital mortality was 11 per 1000 higher for the liberal oxygen therapy group versus the conservative therapy group (95% CI, 2 to 22 per 1000 more). Mortality at 30 days was also higher in the group who had received liberal oxygen (RR 1.14, 95% CI 1.01 to 1.29). The trials included adults with sepsis, critical illness, stroke, trauma, myocardial infarction, cardiac arrest, and patients who had emergency surgery. Studies that were limited to people with chronic respiratory illness or psychiatric illness, or patients on extracorporeal life support, receiving hyperbaric oxygen therapy, or having elective surgery, were all excluded from the review.
An upper SpO ₂ limit of 96% is therefore reasonable when administering supplemental oxygen to patients with acute illness who are not at risk of hypercapnia. However, a higher target may be appropriate for some specific conditions (e.g., pneumothorax, carbon monoxide poisoning, cluster headache, and sickle cell crisis).[132]
In 2019 the BTS reviewed its guidance in response to this systematic review and meta-analysis and decided an interim update was not required.[113]
- The committee noted that the systematic review supported the use of controlled oxygen therapy to a target.
- While the systematic review showed an association between higher oxygen saturations and higher mortality, the BTS committee felt the review was not definitive on what the optimal target range should be. The suggested range of 94% to 96% in the review was based on the lower 95% confidence interval and the median baseline SpO ₂ from the liberal oxygen groups, along with the earlier 2015 TSANZ guideline recommendation.
Subsequently, experience during the COVID-19 pandemic has also made clinicians more aware of the feasibility of permissive hypoxaemia.[133]
Management of oxygen therapy in patients in intensive care is specialised and informed by further evidence that is more specific to this setting.[134][135][136]

Measure arterial blood gases in those with SpO ₂ <94%, those with a risk of hypercapnic ventilatory failure (CO 2 retention), and all patients with high-severity CAP.[1][65]

Fluid resuscitation

Assess all patients for volume depletion and give intravenous fluids if required.[1][65]

Venous thromboembolism (VTE) prophylaxis

Consider prophylaxis for VTE with a low molecular weight heparin for all patients who are not fully mobile.[1][65]

Airway clearance

Do not treat people with uncomplicated pneumonia with traditional airway clearance techniques routinely. If needed, offer these patients advice regarding expectoration of sputum.[1][65]
Consider airway clearance techniques if the patient has difficulty expectorating sputum or if they have a pre-existing lung condition.[1][65]

Analgesia

Give simple analgesia as appropriate (e.g., for pleuritic pain).[1][65]

Primary options

Consider – switch to pathogen-targeted antibiotic therapy

Back

Consider –

switch to pathogen-targeted antibiotic therapy

Additional treatment recommended for SOME patients in selected patient group

Consult with a microbiologist about appropriate pathogen-targeted antibiotic therapy.[1][65]

Switch from empirical antibiotics to pathogen-targeted antibiotics as soon as specific pathogens are identified (unless there are legitimate concerns about dual-pathogen infection).[1][65]

Only about one third to one quarter of patients with CAP admitted to hospital will have their pneumonia defined microbiologically.[1] Among these patients:

Around 14% have an atypical pathogen, of which:[21]
- 7% have Mycoplasma pneumoniae
- 4% have Chlamydophila pneumoniae
- 3% have Legionella pneumophila
Those with infections due to Mycoplasma, Chlamydophila, and Coxiella burnetii will be diagnosed late in the illness on the basis of seroconversion, reducing the opportunity for early targeted therapy.[1]

Consider switching the choice of agent once the results of sensitivity testing are available or following consultation with a microbiologist, intensivist, or respiratory physician.[1]

BTS recommendations for pathogen-targeted antibiotics[1][65]

Pathogen	Preferred antibiotic	Alternative antibiotic
Mycoplasma pneumoniae Chlamydophila pneumoniae	Clarithromycin (orally or intravenously)	Doxycycline (orally) or a fluoroquinolone (orally or intravenously)
Legionella species	Fluoroquinolone (orally or intravenously)	Clarithromycin (orally or intravenously) or azithromycin (in countries where it is used for managing pneumonia)
Streptococcus pneumoniae	Amoxicillin (orally) or benzylpenicillin (intravenously)	Clarithromycin (orally) or cefuroxime or cefotaxime or ceftriaxone (intravenously)
Chlamydia psittaci Coxiella burnetii	Doxycycline (orally)	Clarithromycin (orally or intravenously)
Haemophilus influenzae	Non-beta-lactamase-producing: amoxicillin (orally or intravenously) Beta-lactamase-producing: amoxicillin/clavulanate (orally or intravenously)	Cefuroxime or cefotaxime or ceftriaxone (intravenously) or a fluoroquinolone (orally or intravenously)
Gram-negative enteric bacilli	Cefuroxime or cefotaxime or ceftriaxone (intravenously)	Fluoroquinolone (intravenously) or imipenem/cilastatin (intravenously) or meropenem (intravenously)
Pseudomonas aeruginosa	Ceftazidime (intravenously) plus Gentamicin or tobramycin (dose monitoring required)	Ciprofloxacin (intravenously) or piperacillin/tazobactam (intravenously) plus Gentamicin or tobramycin (dose monitoring required)
Staphylococcus aureus: non-MRSA	Flucloxacillin (intravenously) with or without Rifampicin (orally or intravenously)
Staphylococcus aureus: MRSA	Vancomycin (intravenously; dose monitoring required) or linezolid (intravenously) or teicoplanin (intravenously) with or without Rifampicin (orally or intravenously)

confirmed CAP on chest x-ray: presenting in the community

1st line – continue empirical antibiotics or switch to pathogen-targeted antibiotic therapy

Back

1st line –

continue empirical antibiotics or switch to pathogen-targeted antibiotic therapy

Continue empirical antibiotics in patients with CAP confirmed by chest x-ray in the community. However, where a pathogen has been identified, follow your local antibiotic protocol for the identified organism(s).[1][65]

BTS recommendations for pathogen-targeted antibiotics[1][65]

Pathogen	Preferred antibiotic	Alternative antibiotic
Mycoplasma pneumoniae Chlamydophila pneumoniae	Clarithromycin (orally or intravenously)	Doxycycline (orally) or a fluoroquinolone (orally or intravenously)
Legionella species	Fluoroquinolone (orally or intravenously)	Clarithromycin (orally or intravenously) or azithromycin (in countries where it is used for managing pneumonia)
Streptococcus pneumoniae	Amoxicillin (orally) or benzylpenicillin (intravenously)	Clarithromycin (orally) or cefuroxime or cefotaxime or ceftriaxone (intravenously)
Chlamydia psittaci Coxiella burnetii	Doxycycline (orally)	Clarithromycin (orally or intravenously)
Haemophilus influenzae	Non-beta-lactamase-producing: amoxicillin (orally or intravenously) Beta-lactamase-producing: amoxicillin/clavulanate (orally or intravenously)	Cefuroxime or cefotaxime or ceftriaxone (intravenously) or a fluoroquinolone (orally or intravenously)
Gram-negative enteric bacilli	Cefuroxime or cefotaxime or ceftriaxone (intravenously)	Fluoroquinolone (intravenously) or imipenem/cilastatin (intravenously) or meropenem (intravenously)
Pseudomonas aeruginosa	Ceftazidime (intravenously) plus Gentamicin or tobramycin (dose monitoring required)	Ciprofloxacin (intravenously) or piperacillin/tazobactam (intravenously) plus Gentamicin or tobramycin (dose monitoring required)
Staphylococcus aureus: non-MRSA	Flucloxacillin (intravenously) with or without Rifampicin (orally or intravenously)
Staphylococcus aureus: MRSA	Vancomycin (intravenously; dose monitoring required) or linezolid (intravenously) or teicoplanin (intravenously) with or without Rifampicin (orally or intravenously)

In community settings, the diagnosis of CAP is based on signs and symptoms of lower respiratory tract infection, focal chest signs, and illness severity, and management is based on a suspected diagnosis.[1][63][65] However, a chest x-ray is indicated in the community if:[1][63][65]

There is diagnostic doubt
The patient is deemed to be at risk of underlying lung pathology (e.g., they have risk factors for lung cancer)
Progress following treatment is not satisfactory at review.

Use of this content is subject to our disclaimer

Community-acquired pneumonia in adults (non COVID-19)

Treatment algorithm

suspected CAP: presenting in hospital with life-threatening illness

empirical intravenous antibiotic therapy

Practical tip

supportive care

Evidence: Target oxygen saturation in acutely ill adults

Practical tip

Primary options

These drug options and doses relate to a patient with no comorbidities.

Primary options

Drug choice, dose and interactions may be affected by the patient's comorbidities. Check your local drug formulary.

Primary options

suspected CAP: presenting in hospital without life-threatening illness

supportive care while confirming diagnosis

Evidence: Target oxygen saturation in acutely ill adults

Practical tip

Primary options

These drug options and doses relate to a patient with no comorbidities.

Primary options

Drug choice, dose and interactions may be affected by the patient's comorbidities. Check your local drug formulary.

Primary options

suspected CAP: presenting in the community

high-severity (CRB-65 = 3 or 4)

urgent hospital admission

Practical tip

empirical antibiotic prior to hospital transfer

moderate-severity (CRB-65 = 1 or 2)

hospital referral

low-severity (CRB-65 = 0)

empirical oral antibiotic therapy

supportive care

Primary options

These drug options and doses relate to a patient with no comorbidities.

Primary options

Drug choice, dose and interactions may be affected by the patient's comorbidities. Check your local drug formulary.

Primary options

hospital admission

confirmed CAP on chest x-ray: presenting in hospital

high-severity (CURB-65 = 3-5)

empirical intravenous antibiotic therapy

Practical tip

fluoroquinolone

supportive care

Evidence: Target oxygen saturation in acutely ill adults

Primary options

These drug options and doses relate to a patient with no comorbidities.

Primary options

Drug choice, dose and interactions may be affected by the patient's comorbidities. Check your local drug formulary.

Primary options

switch to pathogen-targeted antibiotic therapy

moderate-severity (CURB-65 = 2)

empirical oral or intravenous antibiotic therapy

More info: EMA and MHRA restrictions on the use of fluoroquinolone antibiotics

Practical tip

supportive care

Evidence: Target oxygen saturation in acutely ill adults

Primary options

These drug options and doses relate to a patient with no comorbidities.

Primary options

Drug choice, dose and interactions may be affected by the patient's comorbidities. Check your local drug formulary.

Primary options

switch to pathogen-targeted antibiotic therapy

low-severity (CURB-65 = 0-1)

empirical oral or intravenous antibiotic therapy

Practical tip

supportive care

Evidence: Target oxygen saturation in acutely ill adults

Primary options

These drug options and doses relate to a patient with no comorbidities.

Primary options

Drug choice, dose and interactions may be affected by the patient's comorbidities. Check your local drug formulary.

Primary options

switch to pathogen-targeted antibiotic therapy

confirmed CAP on chest x-ray: presenting in the community

continue empirical antibiotics or switch to pathogen-targeted antibiotic therapy

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