Hay fever occurs once your body comes into contact with an allergen, usually through the nose, mouth or eyes. Allergens are a foreign substance that triggers an allergic reaction by the immune system.

The reaction involves the release of histamine, the chemical responsible for the symptoms of hay fever.

Allergens are unique to each individual and are often harmless substances that the immune system mistakes for something dangerous. Even small amounts of allergens can cause hay fever in some people if they are particularly sensitive to an allergen.

Common allergens that cause hay fever are dust mites, dust, mould, assorted pollens, animal furs, cigarette smoke, general air pollutants, gluten and latex.

Some people experience what’s known as seasonal hay fever. This occurs during particular seasons of the year due to high amounts of allergens in the air such as pollen.

Unlike most of the world which experiences their hay fever/ allergy season mostly during spring, Australian hay fever season can vary from state to state due to Australia’s size, variety of pollen and different climates. Exactly when you may experience your allergy season may be different to others, but there are general rules.

Melbourne peaks during spring September to November.

Sydney, Adelaide and Canberra have moderate pollen count around spring which then peaks from September to December.

Darwin and Perth have moderate levels all year long with peaks during summer into Autumn from November to February.

In Brisbane, the pollen count remains quite high all year, with peaks from December to April. 

The Northern Territory is quite similar to Brisbane high all year round, peaking in April

Common hay fever symptoms are a runny nose, watery eyes, irritated red eyes, nasal congestion (blocked nose), cough, sneezing and itching of the eyes, mouth or skin.

Less common but more severe hay fever symptoms include fatigue, ear pain, sinus pain, headaches, wheezing, and shortness of breath. Shortness of breath and wheezing tends to occur more in those with asthma and could require a reliever asthma inhaler.

It can be easy to mistake the symptoms of hay fever for the common cold as there are many similarities. The best way to distinguish the difference between the two is the duration of the symptoms. The common cold tends to last for 4 to 7 days whereas hay fever may last hours to days depending on exposure to allergens.

Hay fever can persist long term if you are regularly exposed to allergens.

Allergies and hay fever can be treated and managed in a number of ways. One is lifestyle modification, where you identify what your triggers are and try to avoid them. You can also use medications to help reduce your body’s immune reaction and relieve symptoms. These medications may come in the form of antihistamines, nasal corticosteroids or eye drops. For more persistent allergies, your doctor may recommend immunotherapy.

If you are experiencing a severe allergic reaction, please call 000 for urgent medical attention.

Common side effects will vary depending on which medication you are prescribed.

For nasal sprays and eye drops, common side effects can include: nosebleeds, distaste, irritation or burning sensation in the nose, headaches, dizziness, tiredness, increased amount of nasal discharge or discoloured nasal discharge, coughing, swelling of the face, lips, mouth, tongue or throat, difficulty breathing or swallowing, rashes, blurred vision, irritated eyes and swelling of the eyelids.

For lubricating eye drops, common side effects can include: eye irritation or pain, blurred vision, allergic reactions, headaches, drowsiness and dry mouth.

For antihistamines, common side effects can include: headaches, drowsiness or sedation, lethargy, dry mouth, diarrhoea, gastric upset, reduced appetite, blurred vision, disturbed coordination, sweating, palpitations, hypotension and urinary retention.

Long-term daily use of medications has the potential to cause side effects. Your doctor will advise you on when and how to take your medication in order to manage your symptoms and to minimise any long-term complications.