Topically administered hyaluronic acid in the upper airway: A narrative review

Hyaluronic acid plays a role in controlling inflammatory airway processes and mucociliary clearance, and it is also involved in tissue healing and remodelling. Some studies have tested the effectiveness of topically administered hyaluronic acid in patients with upper airway diseases with positive preliminary results. This article describes the use of topically administered hyaluronic acid in patients with otolaryngological disorders. Pertinent studies published between January 2000 and October 2016 were selected by means of a MEDLINE search using the following terms: 'hyaluronic acid' and 'otolaryngology', 'otitis', 'pharyngitis', 'tonsillitis', 'rhinitis', 'rhinosinusitis' and 'nose'. Twelve of the 19 initially identified papers were selected, corresponding to 902 patients as a whole. There is some evidence that topically administered hyaluronic acid is effective or moderately effective in different otolaryngological conditions, as it improves the global subjective and clinical status of patients with inflammation of the nasopharyngeal and oto-tubaric complex, those with rhinitis or rhinosinusitis and those who have undergone nasal and sinonasal surgery. However, these findings should be viewed cautiously as they are based on a limited number of studies, some of which were probably under-powered because of their small patient samples.