Saline Rinsing for Allergic Rhinitis: A Cochrane Review

Allergic rhinitis is one of the most common reasons a nose gets blocked, and a blocked nose is one of the most common reasons a child or adult starts breathing through the mouth. This Cochrane review — the most rigorous form of evidence synthesis — examined whether rinsing the nasal cavity with saltwater (nasal irrigation, also called douching or lavage) helps relieve the symptoms.

The procedure is deliberately simple: isotonic or hypertonic saline flushed through the nasal passages to wash out allergens and mucus. The review gathered the trials testing it against the full picture of rhinitis symptoms — obstruction, rhinorrhoea, sneezing, and itching — and the toll those take on quality of life.

This matters because keeping the nose clear is the first line of defence against the cascade this project tracks. If a low-cost rinse can ease nasal obstruction, it helps a person stay on the nasal route — preserving the filtering, humidifying, and nitric-oxide functions the mouth can't replicate. Protecting nasal breathing early is far cheaper than treating the facial and airway consequences of chronic mouth breathing later.