Pollen allergies

What is pollen?#

Pollen is a powdery, granular substance found in the flowers of trees, grasses and weeds, and it allows plants to reproduce. Pollen can be spread by insects or carried on the wind. Some people develop allergic symptoms when they are exposed to it. Plants that are not native to an area are more likely to cause seasonal allergies in local people.

It is difficult to avoid pollen, because it is carried in the wind and easily inhaled, but you can take steps to reduce your exposure. Your doctor can also prescribe medication for hay fever and asthma to reduce your symptoms.

If someone is having an asthma attack and breathing is difficult, in case of emergency call your local emergency number (for example 911 in the US and Canada, 112 across the EU and many countries, 999 in the UK, or 000 in Australia) and ask for an ambulance.

Symptoms of pollen allergies#

Everyone’s immune system is different, so allergies to pollen can cause many different signs and symptoms. This can make diagnosing an allergy difficult.

If you think you may have an allergy, keeping a record of your symptoms can help you and your doctor understand what is causing them. Keep a diary describing your symptoms and when and where they occur. It could note 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 a particular food or drink
• after taking a particular medication, whether prescription or bought over the counter
• after taking a herbal medicine

Asthma from pollen allergies#

Pollen can be breathed into the lungs and directly trigger asthma in some people. This can happen separately from hay fever symptoms. Symptoms of asthma include:

• coughing
• chest tightness or pain
• shortness of breath
• difficulty breathing
• wheezing - a whistling noise when breathing

Hay fever symptoms from pollen allergies#

Hay fever is also called allergic rhinitis. The term originally referred only to allergies caused by grass pollens, but it is now used for the symptoms of rhinitis (inflammation of the lining of the nose) in general. When symptoms appear only at certain times of year it may be called seasonal allergic rhinitis, but symptoms can also occur throughout the year.

Hay fever symptoms commonly include:

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

Severe hay fever can affect learning in children and productivity in adults, and can make asthma harder to control. People with hay fever are also more likely to develop sinus infections, and disturbed sleep can lead to extreme tiredness.

Causes of pollen allergies#

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

Pollen allergies are seasonal#

The season for pollen allergies can last several months and occurs when plants are flowering. This varies depending on your location and the type of plant. For example, many trees pollinate in late winter and spring, some grasses release pollen at other times, and certain trees can produce pollen throughout the year and cause symptoms at any time. Pollen counts also vary with the local landscape and wind direction.

Online pollen calendars and forecasts can show when common species cause allergies during the local pollen season, so you can plan to avoid exposure.

Herbal medicines and allergies#

Asteraceae is a family of flowering plants that includes many common species, some of which are used in herbal medicines. Pollen from this family is a common cause of hay fever, asthma and dermatitis. Plants in 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 and feverfew
• plants used in some herbal medicines - echinacea, dandelion, chamomile, feverfew, milk thistle and wormwood

Echinacea can cause severe allergic reactions in some people, including anaphylaxis, asthma attacks and severe hives, and this can occur when the first dose is taken.

Pollen from Asteraceae plants can also cause an allergic skin reaction on contact. The pollen can be found in some herbal medicines, shampoos, cosmetics and massage oils, including products made from plants such as chamomile, chrysanthemum, daisy, dandelion, echinacea, feverfew, sunflower and tansy, as well as royal jelly and bee pollen extracts.

Sensitisation to Asteraceae pollen has also been linked with allergic reactions to similar substances, known as cross-reactivity. This has caused allergic reactions to foods such as celery, honey, sunflower seeds, carrot, lettuce, watermelon and nuts. Always speak with your doctor before using a complementary medicine or therapy.

Diagnosis of pollen allergies#

If you have allergic symptoms that seem to appear at certain times of the year, see your doctor, who will ask questions about your reactions. You can also share the record of your symptoms.

To diagnose your allergy, your doctor may refer you to a clinical immunology or allergy specialist. To test for an allergy to pollen, the specialist may use a skin prick test or a blood test. The results are interpreted together with your clinical history.

Unproven methods to test for allergies#

A number of methods claim to test for allergies but have not been medically or scientifically proven. They can be costly and may lead to dangerous avoidance of certain foods. Methods that are not recommended include:

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

Treatment for pollen allergies#

A direct way to manage pollen allergies is to reduce your exposure. Tips to reduce exposure include:

• staying indoors in the morning if possible, as grass pollens mainly circulate then
• avoiding mowing grass, or wearing a mask if you do, and staying indoors while grass is being mowed
• keeping windows closed in your home and car
• avoiding picnics in parks or the countryside during the pollen season
• wearing sunglasses to protect your eyes
• planting a low-allergy garden around your home, especially near windows

Treatment for hay fever symptoms#

If you cannot avoid pollen, your doctor may suggest medication to reduce hay fever symptoms, including:

• antihistamines, either prescribed or bought over the counter
• nasal corticosteroid sprays to reduce symptoms in the nose, either prescribed or over the counter
• decongestants, taken orally or as a nasal spray

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

Treatment for asthma from pollen allergies#

Asthma can be well controlled with the right medication. If you have asthma triggered by pollen, your doctor will prescribe the correct medication and help you develop an asthma action plan. Make sure you follow it. The main types of medication are:

• relievers, which act quickly to relax the muscles around the airways and are used during an asthma attack
• preventers, which slowly make the airways less sensitive to triggers and reduce inflammation, and are taken daily
• combination therapies, which are preventers containing two different medications

If you have an asthma attack#

In an emergency, call your local emergency number (for example 911 in the US and Canada, 112 across the EU and many countries, 999 in the UK, or 000 in Australia) and ask for an ambulance, and tell the operator that someone is having an asthma attack. Signs of an emergency include when the person:

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

While waiting for the ambulance, follow the person’s asthma action plan and give 4 puffs of reliever medication every 4 minutes.

Immunotherapy for allergies to pollen#

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

Key points#

• It is difficult to avoid pollen because it is carried in the wind and easily inhaled, but you can take steps to reduce your exposure.
• Your doctor can prescribe medication to reduce the symptoms of your body reacting to pollen.
• Allergies to pollen can cause diverse signs and symptoms, which can make diagnosis difficult.
• Keep a diary that describes your symptoms and when and where they occur.
• Pollen can trigger asthma directly, which can be unrelated to hay fever symptoms.

Where to get help#