People with chronic rhinosinusitis or sinus infection are sometimes advised to use steam inhalation or nasal irrigation to relieve symptoms. There is some evidence for nasal irrigation, but little for steam inhalation.
Researchers assigned 871 patients with chronic or recurrent sinusitis to receive usual care, daily nasal saline irrigation, daily steam inhalation or both interventions.
The rhinosinusitis disability index (RSDI) scores showed greater improvement at three and six months in patients given nasal irrigation compared with those without. By six months, more patients maintained a 10-point clinically important RSDI score improvement with nasal irrigation (44.1% versus 36.6%). Steam inhalation only reduced headache.
Reporting in the Canadian Medical Association Journal (online, 18 July 2016)
, the researchers conclude that steam inhalation is not effective and nasal irrigation is less effective than previously thought but provides some benefit.
 Little P, Stuart B, Mullee M et al. A primary care randomised controlled trial of steam inhalation and nasal irrigation for recurrent or chronic sinus symptoms. Canadian Medical Association Journal. doi: 10.1503 /cmaj.160362