Allergies: What they are, why you get them and what to do

Allergic disease is on the rise globally, but Australia has one of the highest rates of allergies in the world.

From hay fever (allergic rhinitis) to asthma and food allergies, more than 5 million Australians live with allergies.¹

Allergies happen when a person’s body reacts to something called an allergen that to most people is harmless.

When the allergen enters your body (through the airways when we breathe, the eyes, digestive system or skin) it triggers the immune system to react. This reaction causes the release of a chemical called histamine which can then cause inflammation in the body. This can result in sneezing, itching or other symptoms.

You might have a reaction if you have an intolerance to something, but it’s only technically considered an allergy when the immune system is activated and overreacts to a foreign substance.

Almost anything can cause an allergic reaction and will depend on the person, but common allergens include:

• food allergies
• bee and insect stings or bites
• latex
• medication
• dust mites
• pollen and grass seed
• pet dander (skin, saliva, fur).

There are many things that can contribute to developing allergies, says CEO of Allergy & Anaphylaxis Australia and National Allergy Council Director, Maria Said.

“There is an allergic gene. So, if one or both of your parents have an allergic disease, you have a much higher chance of getting one too,” says Said.

Climate change may also be part of the reason we’re seeing more allergies. This may be due to increased pollution, prolonged pollination periods and more extreme weather events.²

Overzealous hygiene practices may also be a culprit.

“We live in very clean society,” says Said. “Our immune systems are meant to be able to fight infection, but lack of microorganisms due to cleaning and changes in healthy microorganisms meant to be in our gut causes some of our bodies to lose the plot when we come into contact with things that are actually harmless.”

While genetics plays a big part in whether you will develop an allergy, there may be ways to reduce some risks.

Early and consistent exposure to common allergy causing foods may help prevent food allergies.

“We recommend offering babies at around 6 months old when the baby is ready, not before 4 months old, smooth peanut butter and hard-boiled egg twice a week,” says Said.

If your baby does have an allergic reaction, stop the food and see your doctor.

While hay fever (allergic rhinitis) can’t be prevented, there are ways to reduce symptoms. One is to avoid the allergen as much as you can.

For a dust mite allergy, this might include:

• using dust mite covers for pillows, mattresses and doonas
• washing bedding weekly in hot water (over 60°C)
• washing soft toys in hot water. You can also put them in the freezer to kill dust mites
• reducing soft furnishings such as carpet, curtains, throw pillows and soft toys on or around the bed
• dusting and vacuuming regularly.

For a pollen or grass allergy, this might include:

• wearing sunglasses when outside
• keeping long hair tied up under a cap when outside
• keeping windows closed on windy days
• using the dryer for clothes and sheets to prevent pollen contact when drying outside.

If you have an allergy, you have a higher risk of developing asthma and eczema, but it’s not inevitable.

There’s no way to prevent these allergic diseases, but it’s important to seek medical advice so you can find the most effective management plan for you.

Avoiding your allergen whenever possible can help reduce symptoms, but it’s not always possible.

“Telling someone to get rid of the family pet or rip up their new carpets just isn’t realistic for many,” says Said.

There are over the counter medications that can help treat symptoms of allergies and other issues, but Said recommends seeing a GP to determine what’s best for you.

“Anyone can go into the chemist and get an intranasal corticosteroid spray, but if you’re not using it correctly, or only use it for a few days, you’re unlikely to get the results you need.”

Said suggests thinking about some of these medications as preventative, which can help you get ahead of symptoms.

“If you know you’re allergic to grass and pollen, it might be worth starting medications before spring hits. But always speak to your GP or an allergy specialist first.”

An allergy specialist may recommend testing to see what your exact allergies are. Knowing your allergens can make it easier to treat or avoid them. They may also suggest a treatment called allergen immunotherapy that can take place over several years and has a high rate of success for sufferers of allergic rhinitis.⁴

Allergen immunotherapy involves regularly exposing the person to their allergen in small amounts via injection or orally, over a long period of time. This aims to help the body see the allergen as a harmless entity.

While we may all think we know a thing or 2 about allergies, Said says we don’t always have it right.

“Allergic rhinitis or hay fever is often trivialised. People say, ‘It’s just a runny nose, it’s just a cough’. This can lead to not getting diagnosed with a GP and not treating symptoms, which can have a detrimental impact on sleep, productivity and overall wellbeing. Allergic rhinitis can be well managed, but people need to see a GP or an allergy specialist to learn how to do this effectively.”

“This isn’t true. Sadly, we have also seen deaths from egg and milk allergies in Australia, and any food allergy needs to be taken very seriously.”⁵

While some people only experience symptoms in spring due to having a pollen or grass allergy, a dust mite, grass or mould allergy can be year-round.

This is a popular myth, but it’s not true. Allergies stem from a pet’s dander (skin, saliva and fur), so it’s impossible to completely eradicate allergens in any type of animal.⁶

Allergy & Anaphylaxis Australia has online support resources available. You can also call for help and support on 1300 728 000.

Allergy 250K provides support for teenagers and young adults.