3 Initial approach to antibiotic treatment choices

3 Initial approach to antibiotic treatment choices

3.1 Be aware that:

  • When a patient first presents with suspected pneumonia, it is difficult to differentiate between COVID‑19 pneumonia and bacterial pneumonia on clinical features alone (see recommendations 4.2 and 4.3).

  • During the COVID‑19 pandemic to date most pneumonia has been viral. Evidence so far suggests that bacterial co-infection occurs in less than about 10% of patients with COVID‑19. But patients in critical care have an increased likelihood of bacterial infection compared with patients in other hospital wards or settings.

  • Because COVID‑19 pneumonia is caused by a virus, antibiotics are ineffective unless there is a bacterial co-infection.

  • Inappropriate antibiotic use may reduce their availability, and indiscriminate use may lead to Clostridioides difficile infection and antimicrobial resistance.

When to start antibiotics

3.2 If there is confidence that the clinical features are typical for COVID‑19, it is reasonable not to start empirical antibiotics.

3.3 Empirical antibiotics should be started if there is clinical suspicion of bacterial infection, including characteristic symptoms and localised chest findings. A neutrophil count outside the normal range or lobar consolidation on chest imaging may suggest a bacterial infection but their absence does not exclude it. When a decision to start antibiotics has been made:

  • Start empirical antibiotic treatment as soon as possible after establishing a diagnosis of pneumonia, and certainly within 4 hours.

  • Do not wait for microbiological test results.

  • Start treatment within 1 hour if the patient has suspected sepsis and meets any of the high-risk criteria for this outlined in the NICE guideline on sepsis.

Antibiotic choice

3.4 To guide decision making about antibiotics, use:

  • antibiotic prescribing table 1 for patients with suspected community-acquired pneumonia (that is, pneumonia that has developed before or within 48 hours of admission)

  • antibiotic prescribing table 2 for patients with suspected hospital acquired pneumonia (that is, pneumonia that develops 48 hours or more after admission and that was not incubating at admission).

3.5 When choosing antibiotics, take account of:

  • local antimicrobial resistance data and

  • other factors such as their availability.

3.6 For patients who are already taking an antibiotic that was started in the community for suspected pneumonia:

  • review the antibiotic choice and

  • change the antibiotic in line with antibiotic prescribing table 1, if appropriate.

3.7 Give oral antibiotics if the patient can take oral medicines and their condition is not severe enough to need intravenous antibiotics.

3.8 Seek specialist advice on antibiotic treatment for patients who:

  • are immunocompromised

  • have a history of infection with resistant organisms

  • have a history of repeated infective exacerbations of lung disease

  • are pregnant

  • are in critical care.

Prescribing tables to guide decision making about antibiotic choice

A 2-page summary version of these prescribing tables is also available to download.

Table 1 Antibiotics for people 18 and older with suspected community-acquired pneumonia

Empirical treatment

Antibiotics and dosage (oral doses are for immediate-release medicines)

Oral antibiotics for moderate or severe pneumonia

Options include:

Doxycycline: 200 mg on first day, then 100 mg once a day

Co‑amoxiclav: 500 mg/125 mg three times a day with

Clarithromycin: 500 mg twice a day

In severe pneumonia, and if the other options are unsuitable:

Levofloxacin: 500 mg once or twice a day (consider the safety issues with fluoroquinolones)

Intravenous antibiotics for moderate or severe pneumonia

Options include:

Co-amoxiclav: 1.2 g three times a day with

Clarithromycin: 500 mg twice a day

Cefuroxime: 750 mg three or four times a day (increased to 1.5 g three times a day if infection is severe) with

Clarithromycin: 500 mg twice a day

In severe pneumonia and if the other options are unsuitable:

Levofloxacin: 500 mg once or twice a day (consider the safety issues with fluoroquinolones)

See the BNF for appropriate use and dosing in specific populations, for example, for hepatic impairment, renal impairment, pregnancy and breast-feeding, and when administering intravenous antibiotics.

There are no validated tools to assess the severity of community-acquired pneumonia in the context of the COVID‑19 pandemic; severity should be based on clinical judgement.

Consult a local microbiologist for alternative options, including for pregnant women.

If there is a penicillin allergy, avoid using co‑amoxiclav and use cefuroxime with caution.

For safety issues with fluoroquinolones, see the Medicines and Healthcare products Regulatory Agency advice. This covers restrictions and precautions for using fluoroquinolone antibiotics because of very rare reports of disabling and potentially long-lasting or irreversible side effects affecting musculoskeletal and nervous systems. Warnings include: stopping treatment at the first signs of a serious adverse reaction (such as tendonitis), prescribing with special caution for people over 60 years and avoiding coadministration with a corticosteroid (March 2019).

Table 2 Antibiotics for people 18 and older with suspected hospital‑acquired pneumonia

Empirical treatment

Antibiotics and dosage (oral doses are for immediate-release medicines)

Oral antibiotics for non-severe pneumonia when there is not a higher risk of resistance

Options include:

Doxycycline: 200 mg on first day, then 100 mg once a day

Co-amoxiclav: 500 mg/125 mg three times a day

Co-trimoxazole: 960 mg twice a day (see the BNF for information on monitoring of patient parameters)

If the other options are unsuitable:

Levofloxacin: 500 mg once or twice a day (consider the safety issues with fluoroquinolones)

Intravenous antibiotics for severe pneumonia (for example, symptoms or signs of sepsis or ventilator-associated pneumonia) or when there is a higher risk of resistance

Options include:

Piperacillin with tazobactam: 4.5 g three times a day, increased to 4.5 g four times a day if infection is severe

Ceftazidime: 2 g three times a day

If the other options are unsuitable:

Levofloxacin: 500 mg once or twice a day(use a higher dosage if infection is severe; consider the safety issues with fluoroquinolones)

Antibiotic to be added if meticillin-resistant Staphylococcus aureus infection is suspected or confirmed (dual therapy with an intravenous antibiotic listed above)

Vancomycin: 15 mg/kg to 20 mg/kg two or three times a day intravenously, adjusted according to serum vancomycin concentration. Maximum 2 g per dose (see the BNF for information on patient parameter and therapeutic drug monitoring)

Teicoplanin: Initially 6 mg/kg every 12 hours for 3 doses intravenously, then 6 mg/kg once a day (see the BNF for information on patient parameter and therapeutic drug monitoring)

Linezolid: 600 mg twice a day orally or intravenously (with specialist advice only; see the BNF for information on monitoring of patient parameters)

See the BNF for appropriate use and dosing in specific populations, for example, for hepatic impairment, renal impairment, pregnancy and breast-feeding, and when administering intravenous antibiotics.

There are no validated tools to assess the severity of hospital-acquired pneumonia in the context of the COVID-19 pandemic; severity should be based on clinical judgement.

Consult a local microbiologist for alternative options, including for pregnant women.

If there is a penicillin allergy, avoid using co‑amoxiclav and piperacillin with tazobactam, and use cefuroxime and ceftazidime with caution.

Higher risk of resistance includes symptoms or signs starting more than 5 days after hospital admission, relevant comorbidity such as severe lung disease or immunosuppression, recent use of broad-spectrum antibiotics, colonisation with multidrug-resistant bacteria, and recent contact with a health or social care setting before current admission.

For antibiotics not licensed for hospital-acquired pneumonia (co-trimoxazole, levofloxacin), use would be off-label. See NICE's prescribing medicines for more information.

For safety issues with fluoroquinolones, see the Medicines and Healthcare products Regulatory Agency advice. This covers restrictions and precautions for using fluoroquinolone antibiotics because of very rare reports of disabling and potentially long-lasting or irreversible side effects affecting musculoskeletal and nervous systems. Warnings include: stopping treatment at the first signs of a serious adverse reaction (such as tendonitis), prescribing with special caution for people over 60 years and avoiding coadministration with a corticosteroid (March 2019).