What is hay fever?

The immune system treats a normally harmless substance such as grass, tree or weed pollen as a threat. Chemical signals then cause swelling and mucus in the nasal lining. This explains sneezing, an itchy nose, congestion and a clear runny nose. The same response can affect the eye surface, causing watering and itchiness.

Hay fever is also called seasonal allergic rhinitis, although symptoms can occur whenever a triggering pollen is present. It is different from a cold because it is not caused by a virus and does not spread between people. [Allergic Rhinitis](/conditions/allergic-rhinitis/) covers the related condition in more detail.

Track when symptoms appear and reduce contact with the suspected pollen. Keep bedroom windows closed during high-pollen periods, rinse your face after outdoor time and change clothes before bed. A pharmacist can recommend an antihistamine, nasal spray or eye treatment suited to your age and health.

If the eyes are the main problem, information about [Allergic Conjunctivitis](/conditions/allergic-conjunctivitis/) may help. Cough or wheeze can occur alongside [Asthma](/conditions/asthma/) and should not be dismissed as nasal allergy alone.

Get urgent help if breathing becomes difficult or the lips, tongue or throat swell. Arrange a routine assessment if symptoms interfere with sleep, daily activities or exercise, or if pharmacy treatment is not helping. Persistent facial pain, reduced smell or a long-lasting cough may need evaluation for another condition such as [Sinusitis](/conditions/sinusitis/) or [Chronic Cough](/conditions/chronic-cough/).

Which pollen or exposure might be triggering me? What is the safest treatment with my other medicines? How can I tell allergy symptoms from asthma or infection? When should I return for review?