A recent review paper entitled “Optimising inhaled mannitol for cystic fibrosis in an adult population” published in the Breathe journal, discusses the advantages of mannitol inhalation in Cystic Fibrosis (CF) patients and provides a general procedure for its appropriate administration.

Cystic Fybrosis is a genetic disorder that affects secretory cells that produce mucus, sweat and digestive juices, causing the thickening and stickiness of these secretions. Instead of acting as lubricant, secretions clog up body ducts and airways with severe consequences for the respiratory and digestive systems. CF patients frequently develop chronic airways inflammation and infection, persistent coughing and breathlessness, which untreated could lead to bronchiectasis, hemoptysis and ultimately to a full respiratory failure. Primary treatments to alleviate these symptoms are based on the clearance of secretions from the airways, either mechanically with chest physical therapy or recurring to inhaled dugs.

Mannitol, a natural occurring osmotic agent, has been studied for the treatment of CF as a dry powder of 3-micron spheres. This particle size was optimized to facilitate mannitol inhalation through a disposable inhaler device developed by Pharmaxis Limited. After inhalation, mannitol particles seem to fluidize respiratory mucus and increase the surface hydration of respiratory ducts, promoting the clearance of secretions and thus contributing for an improved lung function.

Two large stage III clinical trials (CF301 and CF302), demonstrated that mannitol inhalation significant improves patients’ lung function. Respiratory progress could be sustained with prolonged treatment, resulting in a lower risk for pulmonary complications even for patients heavily treated with standard therapies. Adverse effects were generally mild or moderate and similar to those of alternative CF treatments, and most of the patients were able to tolerate the treatment. Due to these impressive results, the use of inhaled mannitol in adults was recently approved in Europe.

Despite its benefits, the acceptance of a therapy involving the inhalation of a dry powder by the patients is challenging, especially when higher doses are required. Authors suggest a series of practical considerations to facilitate mannitol inhalation treatment acceptance and efficacy, in which physicians and therapist have a central role. These should provide a clear demonstration of the proper inhaler technique to the patient, encourage the administration of the correct dose, inform patients about inhaled mannitol side effects and set clear expectations with respect to the treatment. In this way, patients will know what to expect from mannitol inhalation and will be motivated to continue with the therapeutics.

Before initiating therapy, patients should be subjected to a mannitol tolerance test to avoid hyperresponsiveness to the treatment and thus further complications. Further information about these guidelines can be found on the original article.