The natural way to breathe Stérimar Nasal Hygiene is a completely natural Isotonic* sea water nasal spray. The salt concentration has been reduced to the same salt level as cells in the human bodies to make it extremely gentle for the nose. It clears allergens, dust and other airborne contaminants from the nose and moisturises nasal passages. It relieves symptoms associated with allergies, hayfever, cold, rhinitis, sinusitis.