Pollen allergies

What is pollen?

Pollen is a powdery, granular substance in the flowers of trees, grasses and weeds that leads to fertilisation of plants. Pollen can be spread by insects or dispersed in the wind. Some people develop symptoms to pollen, such as hay fever (runny nose and itchy and watery eyes), and/or asthma.

Trees and grasses that are not native to Australia are more likely to cause seasonal allergies. It is difficult to avoid pollen because it is in the wind and easily inhaled, but you can take steps to reduce your exposure. Your doctor can prescribe medication for hay fever and/or asthma.

A clinical immunology/allergy specialist may give you a series of injections, which is a treatment called aeroallergen immunotherapy, to reduce the symptoms of your body reacting to the pollen.

If you have an asthma attack and breathing is difficult, in case of emergency, call triple zero (000) and ask for an ambulance.

Symptoms of pollen allergies

Everyone’s immune system is different and allergies to pollens can cause diverse signs and symptoms. This means that diagnosing an allergy can be difficult. If you think you may have an allergy, keeping a record of your symptoms can help you and your doctor to understand what is causing your symptoms.

Keeping a record of your symptoms

Keep a diary that describes your symptoms and when and where they occur. Your diary could include information about whether your symptoms occur:

• inside your home, outside or both
• for a short time or longer
• at night, during the day or when you wake up
• at a particular time of the year
• near animals
• after you have been stung or bitten by an insect
• after you have had a particular food or drink
• after you have taken a particular medication, either prescription or over the counter from a pharmacy or supermarket
• after you have taken a herbal medicine.

Asthma from pollen allergies

Pollen can be breathed into the lungs and directly cause asthma in some people. This can be unrelated to hay fever symptoms. Symptoms of asthma include:

• chest tightness or pain
• shortness of breath
• difficulty breathing
• wheezing – whistling noise when breathing
• coughing.

Hay fever symptoms from pollen allergies

Hay fever may also be referred to as seasonal allergic rhinitis, if the symptoms appear only when it is pollen season. Hay fever originally only referred to allergies caused by grass pollens, but the term is now also used to describe the symptoms of rhinitis (inflammation of the mucous membrane inside the nose). This can occur throughout the year.

Allergies to pollen commonly cause symptoms of hay fever including:

• runny, itchy, congested nose
• sneezing
• irritable, itchy, watery and red eyes
• itchy ears, throat and palate.

People with hay fever are more likely to develop sinus infections, and can have interrupted sleep that leads to extreme tiredness. Severe hay fever symptoms can affect learning in children and productivity in adults. Hay fever can also make it more difficult to control asthma in those who are more likely to get it. People with hay fever are also at risk of thunderstorm asthma.

Causes of pollen allergies

For all allergies, the immune system reacts to specific allergy trigger molecules (allergens). Your immune system produces antibodies that detect the allergen and cause inflammatory reactions and the release of a chemical called histamine. Histamine causes hay fever symptoms, such as itchy and watery nose and eyes, and sneezing.

In Victoria, inland areas tend to have higher pollen counts and northerly winds can bring pollens from inland regions to the coastal areas, including Melbourne. In contrast, the east coast of Australia often has less pollen, because winds tend to blow in from the sea and the Great Dividing Range protects the coast from inland winds. In South Australia and Western Australia, levels of pollen in the air vary, depending on wind direction.

Pollen allergies are seasonal

The season for pollen allergies can last for several months and occurs when the plants are flowering. This will vary depending on location and the type of plant. For instance:

• Non-native trees tend to pollinate in late winter and spring.
• In Victoria, winds from the north tend to bring pollen from non-native grasses growing inland between October and December.
• White Cypress (Murray) pine is the only Australian tree that produces highly allergenic pollen and it flowers approximately between late July and the end of August.
• Species of Casuarina or Australian oak trees produce pollen throughout the year and can cause hay fever symptoms at any time.

Clinical immunology/allergy specialists who diagnose allergies (Australasian Society of Clinical Immunology and Allergy members) have online calendars showing when common species of pollen cause allergies in the states and territories of Australia.

Herbal medicines and allergies

Asteraceae is a family of flowering plants, including many common species, and some are used in herbal medicines. Pollen from plants in this family is a common cause of hay fever, asthma and dermatitis.

Plants from the Asteraceae family include:

• plants grown for their flowers – chrysanthemums, dahlias, sunflowers, marigolds, safflower and daisies
• edible foliage plants – lettuce, safflower, chicory and artichoke
• weeds – ragweed, mugwort, sagebrush, wormwood, feverfew
• plants used in some herbal medicines – echinacea, dandelion, chamomile, feverfew, milk thistle and wormwood.

Echinacea can cause severe allergic reaction (anaphylaxis), asthma attacks, severe hives and swelling in some people, and this can occur when the first dose of echinacea is taken.

Pollen from plants in the Asteraceae family can also cause an allergic skin reaction on contact. The pollen can be found in herbal medicines, shampoos, cosmetics and massage oils, and includes pollen from plants such as the:

• chamomile
• chrysanthemum
• daisy
• dandelion
• echinacea
• feverfew
• sunflower
• tansy.

Sensitisation to pollen of plants from the Asteraceae family has also been linked with allergic reactions to other substances that are similar. This is known as cross-reactivity and has caused allergic reactions to:

• plant-derived herbal medicines – echinacea, royal jelly, bee pollen extracts and chamomile
• foods – celery, honey, sunflower seeds, carrot, lettuce, watermelon and nuts.

Diagnosis of pollen allergies

If you have allergic symptoms that seem to appear at certain times of the year, you should visit your doctor, who will ask some questions about your allergic reactions. You can also discuss your record of your symptoms. To diagnose your allergy, your doctor may refer you to a clinical immunology/allergy specialist.

Clinical immunology/allergy specialists can test for allergies using a number of methods depending on the type of potential allergy. To test for an allergy to pollens, the clinical immunology/allergy specialist may use a skin prick test or a blood test for allergies. The results will be interpreted and considered together with your clinical history.

Information about evidence based allergy testing is available on the Australasian Society of Clinical Immunology and Allergy website.

Unproven methods to test for allergies

A number of methods claim to test for allergies, but they have not been medically or scientifically proven. They can be costly and could lead to dangerous avoidance of certain foods. The organisation representing allergists (Australasian Society of Clinical Immunology and Allergy) recommends that you do not use certain methods to have potential allergies tested. These methods include:

• cytotoxic food testing
• electrodermal testing
• hair analysis
• iridology
• kinesiology
• pulse testing
• reflexology
• Vega testing.

Always speak with your doctor if you are thinking of using a complementary medicine or therapy to test for allergies.

Treatment for pollen allergies

A direct way to manage pollen allergies is to reduce your exposure to pollens. Refer to pollen forecasts so that you can plan to avoid exposure.

Tips to reduce your exposure to pollen include:

• Stay indoors in the morning, if possible – grass pollens mainly circulate in the morning.
• Avoid mowing grass or wear a mask if you do – stay indoors when grass is being mowed.
• Keep windows closed in your home and car.
• Avoid picnics in parks or in the country during the pollen season.
• Wear sunglasses to protect your eyes.
• Plant a low-allergy garden around your home, especially near the windows of your home.

Treatment for hay fever symptoms from pollen allergies

If you are unable to avoid pollen, your doctor may suggest medication to reduce hay fever symptoms including:

• antihistamines – either prescribed or over the counter at a pharmacy
• decongestants – either oral or as a nasal spray
• nasal corticosteroid sprays to reduce symptoms in the nose – either prescribed or over the counter at a pharmacy.

Decongestant tablets and sprays can cause side effects, so use with caution or ask your doctor or pharmacist for advice.

Treatment for asthma from pollen allergies

If you have asthma caused by pollens, your doctor will prescribe the correct medication and help you to develop a plan to manage your asthma. Make sure you follow your asthma action plan.

Asthma can be well controlled with the appropriate medication in almost all people. The main types of medication are:

• Relievers – act quickly to relax the muscles around the airways. This is the medication used during an asthma attack.
• Preventers – slowly make the airways less sensitive to allergy triggers and reduce inflammation inside the airways. These are taken daily.
• Combination therapies – preventers containing 2 different medications.

If you have an asthma attack, follow your asthma action plan. In case of emergency, call triple zero (000) and ask for an ambulance. Tell the operator that someone is having an asthma attack.

The signs of an emergency include when the person:

• finds it very difficult to breathe
• is unable to speak comfortably or if their lips are turning blue
• has symptoms that get worse very quickly
• is getting little or no relief from their reliever inhaler.

While waiting for the ambulance, give 4 puffs of reliever medication every 4 minutes.

Immunotherapy for allergies to pollen

In some cases, your clinical immunology/allergy specialist may suggest allergen immunotherapy which is also known as desensitisation. It involves a series of injections, tablets, sprays or drops given under the tongue of very small doses of the allergen over a long time. This can help to improve tolerance of the pollens that are triggering your allergy and reduce symptoms.

Where to get help

• In an emergency, always call triple zero (000)
• Emergency department of your nearest hospital
• Your GP (doctor)
• NURSE-ON-CALL Tel. 1300 606 024 – for expert health information and advice (24 hours, 7 days)
• Australasian Society of Clinical Immunology and Allergy (ASCIA)
• Asthma Australia Tel. 1800 278 462
• Allergy & Anaphylaxis Australia