COVID-19 acute respiratory infection (Adults)

  • covid smallCOVID-19 is a viral infection.
  • Antivirals or agents with antiviral properties for COVID-19 should not be prescribed for treatment or prophylaxis in the community, unless as part of a clinical trial.
  • Secondary bacterial infection appears uncommon in COVID-19 patients.
  • Role for inhaled budesonide PDF
  • Differentiating viral (COVID-19) versus bacterial pneumonia
    • Viral more likely if;
      • history of typical COVID-19 symptoms for about a week
      • severe muscle pain (myalgia),
      • loss of sense of smell (anosmia), taste (dysgeusia)
      • breathless but has no pleuritic pain
      • history of exposure to known or suspected COVID-19, such as a household or workplace contact.
    • Bacterial more likely if;
      • became rapidly unwell after only a few days of symptoms
      • does not have a history of typical COVID-19 symptoms
      • purulent sputum
      • pleuritic pain
      • underlying chronic lung disease with history of secondary bacterial infection in winters e.g. in acute infective exacerbation of COPD.
  • If antibiotics are prescribed remember:
    • Keep duration as short as possible
    • May cause side effects
    • Broad-spectrum antibiotics in particular may lead to Clostridioides difficile infection
    • Consider drug interactions
    • Consider renal impairment dose adjustment
    • Frail elderly patients are at greater risk of complication and death from all infections. Although there may be a lower threshold for prescribing antibiotics, older patients are also at greater risk of harm from antibiotics.
    • Doxycycline is preferred because it has a broader spectrum of cover than amoxicillin, particularly against Mycoplasma pneumoniae and Staphylococcus aureus, which are more likely to be secondary bacterial causes of pneumonia during the COVID-19 pandemic.
  • Use the following symptoms and signs to help identify patients with more severe illness to help make decisions about hospital admission:
    • severe shortness of breath at rest or difficulty breathing
    • coughing up blood
    • blue lips or face
    • feeling cold and clammy with pale or mottled skin
    • collapse or fainting (syncope)
    • new confusion
    • becoming difficult to rouse
    • little or no urine output.
  •  Further information on COVID-19 Clinical Advice and Guidelines including medicines management is available at the HSE COVID-19 repository



* Alternative doxycycline dose: 100mg every 12 hours.  

 In non-severe infection, 200mg stat then 100mg every 24 hours can be considered.

Patient Information

HSE website: Coronavirus information

Safe Prescribing (visit the safe prescribing page)

  • Doses are oral and for adults unless otherwise stated
  • Penicillin allergy – tips on prescribing in penicillin allergy
  • Renal impairment dosing table
  • Drug interactions table. Extensive drug interactions for clarithromycin, fluoroquinolones, azole antifungals and rifampicin. Many antibiotics increase the risk of bleeding with anticoagulants.
  • Visit the Health Products Regulatory Authority (HPRA) website for detailed drug information (summary of product characteristics and patient information leaflets). Dosing details, contraindications and drug interactions can also be found in the Irish Medicines Formulary (IMF) or other reference sources such as British National Formulary (BNF) / BNF for children (BNFC).

Reviewed May 2021