The fact that macrolide antibiotics may be of therapeutic benefit in some patients with asthma is not surprising because macrolides belong to a family of compounds that possess both immunomodulatory and antimicrobial activity. The proven efficacy of macrolide antibiotics in other chronic respiratory conditions, such as diffuse pan-bronchiolitis, bronchiectasis, and cystic fibrosis,4 has led some physicians to use macrolides in patients with difficult to control asthma. However, whether macrolides “treat” occult atypical bacterial infections or reduce inflammatory processes is unclear. Thus, routine use of macrolide antibiotics in the management of chronic stable asthma cannot be recommended because of the lack of available evidence for their efficacy. Despite these facts, however, there is increasing evidence that some asthmatic patients may be chronically infected or colonized with atypical bacteria and may benefit from macrolide therapy. However, it remains unclear how to best identify this group of patients, as well as the appropriate dose, frequency, and duration of therapy required to eradicate these organisms. Clearly, more research is needed to better elucidate the role of atypical bacteria in the pathogenesis of asthma and to better define the antiinflammatory mechanisms of macrolide antibiotics. Only then will we be able to assess the therapeutic value of macrolides in chronic asthma.