An allergy is your body’s reaction to a particular food or substance. Allergies are extremely common — it’s estimated that more than 1 in 4 people will be affected at some point in their lives. They’re especially widespread among children. Some allergies fade as a child grows older, though many last a lifetime. Understanding the key allergy symptoms can help you identify what’s going on and take action early.
Adults can also develop allergies to things that never bothered them before. While allergies can be unpleasant and affect your day-to-day activities, most allergic reactions are mild and can largely be kept under control.
Signs and symptoms of an allergy
Symptoms of an allergic reaction usually develop within minutes of exposure to something you’re allergic to, although they can occasionally build up gradually over several hours.
Although allergic reactions can be unpleasant and get in the way of your normal activities, most are mild.
On rare occasions, a severe reaction called anaphylaxis can occur.
Common symptoms of an allergic reaction:
- Sneezing and itching,
- runny nose or blocked nose (allergic rhinitis),
- itchy, red, watery eyes,
- wheezing, chest tightness,
- shortness of breath, coughing, asthma,
- a raised, itchy, red rash (hives), eczema,
- swollen lips, tongue, eyes or face,
- stomach pain, nausea, vomiting or diarrhoea,
- dry, red and cracked skin.
Symptoms vary depending on what you’re allergic to and how you come into contact with it.
TIP: Allergic reaction on the face
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For instance, you might get a runny nose when exposed to pollen or dust mites. A rash may appear if you have a skin allergy, or you might feel nauseous after eating something you’re allergic to.
If you or your child may have had an allergic reaction to something, see your GP. They can help determine whether the symptoms are caused by an allergy or another condition.
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Severe allergic reaction (anaphylaxis)
In rare cases, an allergy can lead to a severe reaction called anaphylaxis or anaphylactic shock, which can be life-threatening. It affects the whole body and usually develops within minutes.
Signs of anaphylaxis include any of the symptoms listed above, plus:
- Swelling of the throat and mouth.
- Difficulty breathing.
- Dizziness, confusion.
- Blue skin or lips.
- Collapse and loss of consciousness.
What types of allergies are there?
The substances that trigger allergic reactions are called allergens.
Common allergens include:
- grass and tree pollen – an allergy to these is known as hay fever (allergic rhinitis)
- dust mites (also known as dust and feather allergy)
- animal dander
- food – especially nuts, fruit, shellfish, eggs and cow’s milk
- insect bites and stings
- medications – including ibuprofen, aspirin and certain antibiotics
- latex – used to make some gloves and condoms
- mould – which can release tiny particles into the air that you breathe in
- household chemicals – including those found in detergents and hair dyes
Most of these allergens are generally harmless to people who aren’t allergic to them.
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How to find out if you have an allergy
See your GP if you think you or your child may have had an allergic reaction to something. The symptoms of an allergic reaction can also be caused by other conditions (such as chronic fatigue).
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See your doctor
Your GP can help determine whether you’re likely to have an allergy. If they think you may have a mild allergy, they can offer advice and treatment to help you manage the condition. If your allergy is particularly severe — or it’s unclear what you’re reacting to — they may refer you to an allergy specialist for testing and treatment guidance.
Blood tests
Blood tests can be used instead of, or alongside, skin prick tests to help diagnose common allergies. A sample of your blood is taken and analysed for specific antibodies produced by your immune system in response to an allergen.
Patch tests
Patch tests are used to investigate a type of eczema known as contact dermatitis, which can be caused by your skin being exposed to an allergen. A small amount of the suspected allergen is applied to special metal discs, which are then taped to your skin for 48 hours and monitored for a reaction.
Skin prick testing
This involves placing a drop of liquid on your forearm that contains a substance you may be allergic to. The skin beneath the drop is then gently pricked. If you’re allergic to the substance, an itchy red bump will appear within 15 minutes. Most people don’t find skin prick testing particularly painful, though it can be a little uncomfortable.
The skin prick test is one of the most common allergy tests.
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Allergy medications
There are also several medications that can help control the symptoms of allergic reactions.
- Antihistamines – these can be taken when you notice symptoms of a reaction, or before exposure to an allergen, to prevent a reaction from happening.
- Decongestants – tablets, capsules, nasal sprays or liquids that can be used as a short-term treatment for a blocked nose.
- Nasal sprays and drops – sprays that are non-addictive and can be used repeatedly.
- Steroid medications – sprays, drops, creams, inhalers and tablets that can help reduce redness and swelling caused by an allergic reaction.
For some people with very severe allergies, a treatment called immunotherapy may be recommended. This involves controlled exposure to the allergen over a period of years, so the body gradually gets used to it and stops reacting so strongly.
Allergy prevention
Avoid your allergens. It sounds simple, but it isn’t always easy. Some allergens are easier to dodge than others. When you can’t avoid an allergen completely, try to reduce your contact with it as much as possible.
If you suffer from pollen allergy, we recommend following a pollen calendar, where you can see exactly what’s in bloom each month. This can be a real lifesaver when it comes to preventing pollen allergy flare-ups.
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Another fantastic ally for allergy sufferers at home is an air purifier. These devices are designed to clean the air in a room by capturing allergens and pushing filtered, clean air back into the space. Most air purifiers trap particles like dust and pollen, but the best air purifiers remove particles larger than 0.3 microns, including animal dander — a common allergy trigger.
Got a blocked nose from an allergy or a cold? A nasal rinse can help. You pour a saline (physiological) solution into one nostril, and as it flows through the nasal cavity and out the other nostril, it flushes out mucus and allergens. Using a saline rinse just once a day can help thin mucus, reduce post-nasal drip and clear bacteria from the nasal passages.
And what’s the best way to prevent dust mites? Anti-dust-mite covers for duvets, pillows and mattresses, along with anti-dust-mite duvets, pillows, sheets and bedding. High-quality anti-allergy textile products with nano-fabric won’t just make your life easier — they’ll improve the quality of your sleep, too.
