Constant clear runny nose: common causes and care

Clear nasal fluid is produced when the lining of the nose reacts to an irritant or infection. Allergic rhinitis may cause repeated sneezing, itchy eyes, and symptoms around pollen, dust mites, or pets. A common cold, influenza, or COVID-19 can begin with clear drainage and may add sore throat, cough, tiredness, or fever.

Sinusitis more often causes blocked breathing, facial pressure, reduced smell, or thicker discharge, although symptoms can vary. Non-allergic triggers include smoke, strong scents, dry air, temperature changes, and spicy food. The colour of nasal fluid alone does not establish a diagnosis.

Use saline nasal spray or rinse with properly prepared water, keep rooms free of smoke and strong fragrance, and wash hands after blowing your nose. If an allergy pattern is clear, reduce exposure to the suspected trigger and discuss a suitable antihistamine or nasal treatment with a pharmacist or clinician.

Arrange a routine review if the runny nose persists, repeatedly returns, disrupts sleep, or causes mouth breathing. Note triggers, season, home or workplace exposures, accompanying eye symptoms, and any medicines already tried.

Seek prompt medical help for difficulty breathing, swelling of the lips or face, severe facial pain, eye swelling, confusion, dehydration, or a severe headache with neck stiffness. A clear one-sided leak after a head injury also needs urgent assessment.

Ask whether the pattern fits allergic rhinitis, infection, sinusitis, or non-allergic irritation; which nasal treatment is appropriate; and whether persistent one-sided symptoms need examination.