Anaphylaxis – avoiding dietary triggers

True allergic reactions are rare but when they occur they can be life threatening. One particularly alarming type of allergic reaction is known as anaphylaxis and there are several foods that trigger this type of reaction.
What is anaphylaxis?
Anaphylaxis is a type of allergic reaction that can develop quickly. The symptoms can be quite alarming and include:
- Itchy skin or a raised, red skin rash
- Swelling around the eyes, lips, tongue throat, hands and feet
- Wheezing and breathing difficulties
- Abdominal pain, nausea and vomiting
- Feeling faint
What causes anaphylaxis?
This type of allergic reaction is the result of the body’s immune system overreacting to components in food or other usually harmless substances, such as antibiotics or latex.
Substances that trigger allergic reactions are known as allergens.
More than half of all food related anaphylaxis is caused by peanuts. Other dietary triggers include:
- Tree nuts such as walnuts, cashew nuts, almonds, brazil nuts and hazelnuts
- Milk
- Fish and shellfish
- Eggs
- Some types of fruit – such as bananas, kiwi fruit, grapes and strawberries
How quickly does anaphylaxis happen?
Most reactions occur within minutes of contact with an allergen but sometimes the reaction can take up to four hours.
Who is affected by anaphylaxis?
People of all ages can be affected by anaphylaxis. People who suffer from allergic conditions such as asthma and eczema are most at risk.
Preventing an anaphylaxis reaction
If you have experienced an allergic reaction it is important to identify the allergen that triggered it so steps can be taken to avoid the allergen in future.
Sometime it is clear what the allergen is but not always. A referral to a specialist allergy clinic can help to identify triggers for anaphylaxis.
What is allergy testing?
Allergy testing aims to identify the allergen responsible for causing anaphylaxis. It may include skin prick tests and taking a blood sample to test the body’s reaction to a range of established allergens.
Management of anaphylaxis.
Anaphylaxis is managed by strict avoidance of the offending allergen and the prescription of emergency medication when required.
Avoiding a food trigger may be complicated because leaving whole food groups out of the diet can lead to a dietary deficiency. Consultation with a dietitian can provide individualised advice regarding the foods to avoid and suitable substitute foods.
Food labels
It is important to check food labels for information on problem ingredients. Food manufacturers frequently change their ingredients so it is important to check labels each time you buy a food.
Some manufacturers use the phrase ‘may contain’ to indicate accidental traces of an allergen on a seemingly unrelated product. Strict avoidance of these products is necessary if your anaphylaxis is triggered by even a trace of an allergen.
EU Labelling of major food allergens
Since December 2014 all the 14 major food allergens need to be clearly identified on food labels. In addition food businesses are required to provide allergy information on food sold unpackaged, in for example catering outlets, deli counters, bakeries and sandwich bars. The Food Standards Agency website has further information on this at www.food.gov.uk
Eating out
There are a growing number of ‘Free From’ restaurants that provide a detailed account of the ingredients used in the dishes, and any potential food allergens. Always ask the restaurant manager or chef if any food you are allergic to is present in the meal you would like to eat.
If you are not sure about a dish or about the information you have been provided, don’t risk it. Don’t order the dish or eat at the premises.
Getting help in an emergency
A person with anaphylaxis should not be moved. Emergency medication should be administered if available otherwise call 999 for an ambulance and a paramedic.