Antibiotics not effective for cough and coloured sputum (acute bronchitis)

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Antibiotics not effective for cough and coloured sputum (acute bronchitis)

In this clinical trial, 416 adults presenting with less than one week of cough, discoloured sputum, and at least one other symptom of lower respiratory tract infection (dyspnoea, wheezing, chest discomfort, or chest pain) were randomised to amoxicillin clavulanate 500 mg/125 mg, ibuprofen 600 mg TDS or placebo for 10 days.1

Patients with asthma, COPD, CHF, immunosuppression, severe symptoms or contraindications to NSAIDs were excluded.

At 10 days there was no difference in the resolution of cough between the three groups. This suggests that the coloured sputum in respiratory tract infections is either not representative of infection or if it is then antibiotics make no difference.

Either way, antibiotics do not change the outcome in respiratory tract infection with cough and coloured sputum (sometimes called acute bronchitis).

This is consistent with the findings of another large study using amoxicillin versus placebo.2 Both studies have a low risk of bias.


  1. Efficacy of anti-inflammatory or antibiotic treatment in patients with non-complicated acute bronchitis and discoloured sputum: randomised placebo controlled trial. BMJ 2013. Click here
  2. Amoxicillin for acute lower-respiratory-tract infection in primary care when pneumonia is not suspected: a 12-country, randomised, placebo-controlled trial. Lancet Infectious Diseases 2013. Click here 

    Gems are chosen by the Goodfellow director Dr. Bruce Arroll to be either practice changing or practice maintaining. The information is educational and not clinical advice.


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    As published in NZ Doctor 01/02/2017