Typical symptoms of sinusitis and hay fever include a blocked runny nose, sneezing, itchy eyes, nose or throat.

Rinsing (douching) the sinuses

Nasal irrigation with saltwater has been proven to improve symptoms of allergic rhinitis in adults and children. It works by washing away allergens and mucus, as well as reducing inflammation and swelling in the nasal cavities. The evidence is so strong, it was included as part of the international  2021 consensus on how to manage common sinus issues. There a number of apparatus available commercially but the one featured in the video below called Rhineeze stands out as it does not require batteries or refills and, speaking from experience, it has just the right amount of saline volume and power to comfortably wash out the nose. 2-3 times is the recommended amount.