A food allergy is where your body reacts to certain foods. It's often mild, but can be very serious for some people.
Symptoms of a food allergy can affect any part of the body, including different parts of the body at the same time.
Common symptoms of a food allergy include:
You may get symptoms straight after eating the food you're allergic to, or days later.
A food allergy is different from having a food intolerance, which causes symptoms such as bloating and tummy pain, usually a few hours after eating the food you're intolerant to.
You or the person who's unwell may also have a rash that's swollen, raised or itchy.
These can be signs of a serious allergic reaction and may need immediate treatment in hospital.
If you or someone you're with is having a serious allergic reaction and has an adrenaline auto-injector (such as an EpiPen), you should use it immediately.
Instructions are included on the side of the injector if you forget how to use it or someone else needs to give you the injection.
Call 999 for an ambulance after using the injector, even if you or the person you're with seems to be feeling better.
A food allergy is caused by your immune system overreacting to certain types of food.
It's not clear why this happens, but certain foods are more likely to cause an allergic reaction in some people.
The most common allergic foods include:
But you can be allergic to any type of food, including celery, mustard, sesame seeds and lupin flour found in some baked goods.
You have a slightly higher chance of getting a food allergy if you or a close family member have other allergies, asthma or eczema.
Some people get an itchy mouth and throat after eating raw fruit or vegetables. This is called oral allergy syndrome.
It's not usually serious and eating fruit and vegetables that have been well cooked helps.
You may be referred to a specialist for tests if a GP thinks you have a food allergy.
Tests you may have include:
You may also be asked to keep a food and symptoms diary to help work out what may be triggering your symptoms.
If you have a food allergy, you will not be able to eat the food you're allergic to, including foods where you're allergic to any of the ingredients.
You'll be given medicines to help manage your symptoms or use in case of an emergency.
These include:
Your specialist will give you an allergy management plan that will explain how to manage your allergy.
Children with a peanut allergy may have immunotherapy to help their bodies become less sensitive to peanuts, but they should still avoid eating peanuts.
There are steps you can take to help manage your food allergy.
check food labels and restaurant menus carefully to make sure they do not contain the food you're allergic to
tell friends, family, nursery, school and work about your allergy
carry 2 adrenaline auto-injectors with you at all times, if you need them
tell staff at restaurants and cafés about your allergy
tell airlines and cabin staff about your allergy before you fly
wipe down surfaces in public before eating
do not eat foods without checking what ingredients are in them first
do not cut foods out of your diet without speaking to a GP