Food Allergy
Symptoms of a food allergy
Source: NHS
In this topic (7)
The symptoms of a food allergy almost always develop afew seconds or minutes after eating the food.
Some people may develop a severe allergic reaction (anaphylaxis), which can be life threatening.
Themost common type ofallergic reaction to food is known as an IgE-mediated food allergy.
Symptoms include:
- tingling or itching in the mouth
- a raised, itchy red rash (urticarial) in some cases, the skin can turn red and itchy, but without a raised rash
- swelling of the face, mouth (angioedema) , throator other areas of the body
- difficulty swallowing
- wheezing or shortness of breath
- feeling dizzy and lightheaded
- feeling sick (nausea) or vomiting
- abdominal pain or diarrhoea
- hay fever -like symptoms, such as sneezing or itchy eyes (allergic conjunctivitis)
Anaphylaxis
The symptoms of a severe allergic reaction (anaphylaxis) can be sudden and get worse very quickly.
Initial symptoms of anaphylaxis are often the same as those listed above and can lead to:
- increased breathing difficultiessuch as wheezing and a cough
- a sudden and intense feeling of anxiety and fear
- a rapid heartbeat (tachycardia)
- a sharp and sudden drop in your blood pressure, which can make you feel lightheaded and confused
- unconsciousness
Anaphylaxis is a medical emergency. Without quick treatment, it can be life threatening. If you think you or someone you know is experiencing anaphylaxis, dial 999 and ask for an ambulance as soon as possible.
Non-IgE-mediated food allergy
Another type ofallergic reaction is a non-IgE-mediated food allergy. The symptoms of this type of allergy cantake much longer to develop sometimesup to several days.
Some symptoms of a non IgE-mediated food allergymay be what you would expect to see in an allergic reaction, such as:
- redness and itchiness of the skinalthough not a raised, itchy red rash (urticarial)
- the skin becomes itchy, red, dry and cracked (atopic eczema)
Other symptoms can be much less obvious and are sometimes thought of as being caused by something other than an allergy. They include:
- heartburn and indigestion caused by stomach acid leaking up out of the stomach (gastro-oesophageal reflux disease)
- stools (faeces)becoming much more frequent or loose though not necessarily diarrhoea
- blood and mucus in the stools
- in babiesexcessive and inconsolable crying, even though the baby is well fed and doesn't need a nappy change (colic)
- constipation
- redness around the anus, rectum and genitals
- unusually pale skin
- failure to grow at the expected rate
Mixed reaction
Some children can have a mixed reaction where they experience both IgE symptoms, such as swelling, and non-IgE symptoms, such as constipation.
This can happen to children who have a milk allergy.
Articles for Food Allergy
Causes of a food allergy
A food allergy is caused when your immune system mistakenly treats harmless proteins found in certain foods as a threat. It releases a number of chemicals, which then triggers an allergic reaction.
Diagnosing food allergy
If you think you or your child has a food allergy, make an appointment with your GP.
Introduction
A food allergy is when the body's immune system reacts unusually to specific foods. Allergic reactions are often mild, but they can sometimes be very serious.
Living with a food allergy
The advice here is primarily written for parents of a child with a food allergy. However, most of it is also relevant if you're an adult with a food allergy.
Patient story: "I had my first anaphylactic reaction when I was 18."
Alexis Manning has a peanut allergy. She first found out that she was allergic to peanuts as a child. Some sweets just tasted bad and made her lips swell a bit, and it didn't take long to work out the cause.
Symptoms of a food allergy
Symptoms of a food allergy include a raised, itchy red rash, swelling of the face, eyes, lips and tongue, and shortness of breath.
Treating a food allergy
Once you have been diagnosed as having a food allergy, you will receive advice about antihistamines, adrenaline and using an auto-injector.