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• » Introduction
• » Symptoms of anaphylaxis
• » Causes of anaphylaxis
• » Treating someone who has anaphylaxis
• » Preventing anaphylaxis
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If you have anaphylaxis, you should be offered advice and medication to help prevent further episodes.

Allergy clinic

To discover what caused the anaphylaxis you should be referred to a specialist allergy clinic for tests. Knowing what allergen triggered the allergic reaction may help you avoid further episodes of anaphylaxis.

Some of the tests commonly used to determine allergies include:

• a skin prick test - your skin is pricked with a tiny amount of a suspected allergen to see if it reacts by becoming red, raised and itchy
• a blood test - a sample of your blood is taken to test its reaction to a suspected allergen

Read more about diagnosing allergies and allergy testing.

Adrenaline auto-injectors

If you have experienced a previous episode of anaphylaxis and there's a risk of you having another episode in the future, you may be prescribed an adrenaline auto-injector.

There are three types of auto-injector:

• EpiPen
• Anapen (although these are being withdrawn from use)
• Jext

Each type is slightly different, so you should make sure you know how to use your device correctly.

A health professional should train you how to use the auto-injector. You can also ask for a ‘trainer’ kit so you can practice giving yourself (or your child) injections.

Instructions about how to use the different auto-injectors will be also provided with the device and can be found on their websites.

The following points are important.

• Carry your auto-injector at all times; there should be no exceptions. In some case you may be recommended to carry multiple injectors. Check with your GP or the doctor in charge of your care. It may also be recommended you get an emergency card or bracelet with full details of your allergy and contact details of your doctor, to alert others.
• Extremes of heat can make adrenaline less effective so do not leave your auto-injector in places such as your fridge or the glove compartment of your car.
• Check the expiry date regularly. An out-of-date injector will only offer limited protection.
• The manufactures offer a reminder service where you can be contacted near the date of expiry. Check the information leaflet that comes with your medication for more information.
• If your child has an auto-injector they will need to change over to an adult dose once they reach 30 kilos (4.7 stone).
• Do not delay in injecting yourself if you think you may be experiencing the beginning of anaphylaxis, even if your initial symptoms are mild. It is better to use adrenaline early and then find out it was a false alarm than delaying treatment until you are sure you are experiencing severe anaphylaxis.

Avoid triggers

If a trigger has been identified as being responsible for your episode of anaphylaxis, you will need to take steps to avoid it in future.

Food

If the trigger was a certain type of food, then taking some basic precautions should help you avoid an episode of anaphylaxis in the future. You can reduce the chances of being exposed to a food allergen by:

• checking the labels of foods you eat
• letting staff at a restaurant know what you are allergic to so it's not included in your meal
• remembering some types of food may contain small traces of potential allergens – for example, some sauces contain wheat and peanuts

See living with a food allergy for more information.

Insect stings

You can reduce your risk of being stung by an insect by taking basic precautions, such as:

• if you encounter wasps, hornets or bees, move away from them slowly without panicking, do not wave your arms around or swat at them
• use an insect repellent if you are planning to spend time outdoors, particularly in the summer
• wear a long sleeved top and long trousers, socks and shoes and avoid bright colours and strong perfumes or lotions
• keep the windows of your car closed to stop insects getting inside

Some specialist allergy centres can also offer special treatment to help desensitise you to insect stings if you are at a particularly high risk (such as being a beekeeper or gardener).

Read more about preventing insect stings.

Medication

If you are allergic to certain types of medication, there are normally alternatives that can be safely used. For example, if you are allergic to:

• penicillin you can normally safely take a different group of antibiotics known as macrolides
• the non-steroidal anti-inflammatory drugs (NSAIDs) type of painkillers, such as ibuprofen and aspirin, you can normally safely take paracetamol - read the ingredients of things like cold medicines carefully to ensure they do not contain NSAIDs
• one type of general anaesthetic, others are available, or it may be possible to perform surgery using a local anaesthetic or an epidural injection
• angiotensin-converting enzyme (ACE) inhibitors, then alternative blood pressure medications such as calcium channel blockers can be used

It is important you tell anybody giving you medical care about any medication allergies you have. It is safer not to assume they already know.

Contrast agents

There may be times when it is necessary to use contrast agents - for example, if you had bleeding inside your brain - even if this places you at risk of anaphylaxis.

In such circumstances, you can be given injections of antihistamines and corticosteroids before the contrast agents, which may help prevent symptoms occurring or at least make symptoms less severe.