Aerosolized antimicrobial agents have been used in clinical practice since the 1950s. The main advantage and aim of using this route of administration is delivery of the drug to the site of infection in the lung. Achieving this aim may produce high concentrations in the site of infection or colonization and reduce systemic toxicity to a minimum. The most convincing data to support the use of aerosolized antimicrobials comes from their use as maintenance treatment in patients with cystic fibrosis. In addition to this indication, the use of aerosolized antimicrobials has also been studied in the treatment or prevention of a series of other diseases, including noncystic fibrosis bronchiectasis, ventilator-associated pneumonia, prophylaxis against fungal lung infections, mycobacterial lung infections and, more recently, in chronic obstructive pulmonary disease. Although the theoretical bases underlying aerosol antibiotic administration seem convincing, there is insufficient evidence to support its routine use. Due to the gaps in knowledge that persist in the routine use of aerosolized antibiotics, caution should be exercised in situations without clearly established indications for this modality, such as the treatment of patients with cystic fibrosis, bronchiectasis or Pneumocystis pneumonia.
