Oral versus inhaled antibiotics for people with bronchiectasis

Review question

We wished to know whether oral antibiotics (taken by mouth) or inhaled antibiotics are more effective for reducing the duration and frequency of infective episodes of bronchiectasis, admissions to hospital and side effects, as well as reducing the risk of chest infections not responding to treatment with antibiotics.


Bronchiectasis is a long-term incurable condition where people get repeated bacterial chest infections that lead to frequent cough, breathlessness and mucus production. These often occur three or more times a year and require treatment with antibiotics, either short-term for the presenting chest infection, or long-term to prevent chest infections recurring. It was once thought to be an uncommon disease but recent figures show that up to 5 people in every 1000 may have bronchiectasis and the death rate for people with the condition may be more than twice that of the general population.

Antibiotics are commonly used to treat chest infections in people with bronchiectasis, to eliminate the specific types of bacteria that cause the infection. Some antibiotics are more effective against particular types of bacteria compared to others, and these different types of bacteria can develop resistance to treatment with antibiotics, making them less effective and reducing the subsequent choice of antibiotic. Antibiotics can also be given to people in different ways, such as by mouth in pill form or breathed in as an inhalation.

We do not currently know which method of administering antibiotics, orally or by inhalation, is the most effective for treating recurrent chest infections in terms of eliminating the bacteria, reducing the chances of people developing resistance to antibiotics and reducing the symptoms of bronchiectasis.

We searched for all the published and unpublished available evidence, up until March 2018, which compared orally administered antibiotics versus inhaled antibiotics.

Study characteristics

While there have been a few studies investigating the benefits of antibiotics for people with bronchiectasis, none have compared orally administered antibiotics with inhaled antibiotics.

Quality of the evidence

There is no high-quality evidence available to determine whether oral or inhaled antibiotics are more helpful for people with bronchiectasis. More research studies are needed to evaluate the effectiveness of oral antibiotics compared to inhaled antibiotics for reducing the rate of chest infections and the chances of developing resistance to antibiotic therapy.

Authors' conclusions: 

There is currently no evidence indicating whether orally administered antibiotics are more beneficial compared to inhaled antibiotics. The recent ERS bronchiectasis guidelines provide a practical approach to the use of long-term antibiotics. New research is needed comparing inhaled versus oral antibiotic therapies for bronchiectasis patients with a history of frequent exacerbations, to establish which approach is the most effective in terms of exacerbation prevention, quality of life, treatment burden, and antibiotic resistance.

Read the full abstract...

Bronchiectasis is a chronic inflammatory disease characterised by a recurrent cycle of respiratory bacterial infections associated with cough, sputum production and impaired quality of life. Antibiotics are the main therapeutic option for managing bronchiectasis exacerbations. Evidence suggests that inhaled antibiotics may be associated with more effective eradication of infective organisms and a lower risk of developing antibiotic resistance when compared with orally administered antibiotics. However, it is currently unclear whether antibiotics are more effective when administered orally or by inhalation.


To determine the comparative efficacy and safety of oral versus inhaled antibiotics in the treatment of adults and children with bronchiectasis.

Search strategy: 

We identified studies through searches of the Cochrane Airways Group's Specialised Register (CAGR), which is maintained by the Information Specialist for the group. The Register contains trial reports identified through systematic searches of bibliographic databases including the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, CINAHL, AMED, and PsycINFO, and handsearching of respiratory journals and meeting abstracts. We also searched ClinicalTrials.gov and the WHO trials portal. We searched all databases in March 2018 and imposed no restrictions on language of publication.

Selection criteria: 

We planned to include studies which compared oral antibiotics with inhaled antibiotics. We would have considered short-term use (less than four weeks) for treating acute exacerbations separately from longer-term use as a prophylactic (4 weeks or more). We would have considered both intraclass and interclass comparisons. We planned to exclude studies if the participants received continuous or high-dose antibiotics immediately before the start of the trial, or if they have received a diagnosis of cystic fibrosis (CF), sarcoidosis, active allergic bronchopulmonary aspergillosis or active non-tuberculous Mycobacterial infection.

Data collection and analysis: 

Two review authors independently applied study inclusion criteria to the searches and we planned for two authors to independently extract data, assess risk of bias and assess overall quality of the evidence using GRADE criteria. We also planned to obtain missing data from the authors where possible and to report results with 95% confidence intervals (CIs).

Main results: 

We identified 313 unique records through database searches and a further 21 records from trial registers. We excluded 307 on the basis of title and abstract alone and a further 27 after examining full-text reports. No studies were identified for inclusion in the review.