Basis for not recommending antibiotics for people with acute bronchitis who are otherwise well

• Antibiotics should be reserved for people where there is a risk of serious harm from even a modest deterioration in their chronic condition, or for people who are at risk of a more severe infection because their ability to deal with infection is impaired.
• For people with acute bronchitis who do not have pre-existing pulmonary disease, there is evidence from a Cochrane systematic review that antibiotics have a modest effect in reducing the duration of cough in some individuals.
• Although there is evidence of benefit, the magnitude of this benefit needs to be balanced against the probability of harm from antibiotics for the individual. Some studies have estimated that adverse effects of antibiotics are as frequent as any beneficial effects [SIGN, 2002].
• Current evidence suggests that resistance to the main pathogens implicated in acute bronchitis is not yet widespread in the UK, but increased prescribing of antibiotics is a known mechanism of bacterial resistance, and countries with widespread prescribing of antibiotics in primary care also tend to exhibit greater levels of resistance. Therefore it is prudent not to prescribe antibiotics for self-limiting illnesses whenever possible.
• Based upon considerations of benefit, harms, and increased antibiotic resistance, there is widespread agreement amongst experts that antibiotics are not recommended for people with acute bronchitis who do not have any significant pre-existing conditions.

[Fahey et al, 2004; Braman, 2006]

Basis for considering a delayed prescription strategy for people with acute bronchitis who are otherwise well

• There is evidence that delayed antibiotic prescribing is an effective strategy for managing acute bronchitis. There is no difference in antibiotic consumption between the delayed and no prescribing strategies, and people given delayed prescriptions do not develop diarrhoea significantly more than people offered a no antibiotic prescribing strategy.
• A potential advantage of the delayed prescribing strategy is that it offers a safety net for the small proportion of people with acute bronchitis who develop complications or whose symptoms worsen significantly. A person with acute bronchitis may also prefer to have a delayed prescription rather than no prescription at all, and this could help to maintain the doctor-patient relationship [NICE, 2008].

Basis for considering antibiotics for people with acute bronchitis who are unwell with other conditions

• With the exception of people with COPD, CKS found no direct evidence to support the use of antibiotics for people with acute bronchitis and other conditions.
• Recommendations for when to prescribe an antibiotic in people with a pre-existing condition are therefore based upon:
• Extrapolation from the evidence of the benefit of antibiotics for people who do not have a pre-existing condition, and the assumption that people with pre-existing conditions who are at greater risk of harm from acute bronchitis would gain greater benefit from treatment.
• Evidence of benefit of antibiotics for people with acute bronchitis and COPD. For further information, see the CKS topic on Chronic obstructive pulmonary disease.
• Expert opinion issued in guidelines for the management of adult respiratory tract infections by the European Respiratory Society [Woodhead et al, 2005]. This recommends prescribing antibiotics for people with certain co-existing conditions and people over 75 years of age with fever.
• Additional advice to treat people who are immunocompromised is a pragmatic recommendation from CKS.
• Antibiotics should be reserved for people where:
• There is a risk of serious harm from even a modest deterioration in their chronic condition caused by acute bronchitis.
• They are at risk of a more severe infection because their ability to deal with infection is impaired.