What are the Causes and Symptoms?
Anaphalaxis affects approximately 1% of the Canadian population. It is critical for people who have food allergies to identify them and to avoid foods that cause allergic reactions. Some foods can cause severe illness and, in some cases, a life-threatening allergic reaction (anaphylaxis) that can constrict airways in the lungs, severely lower blood pressure, and cause suffocation by the swelling of the tongue or throat.
Food allergy patterns in adults differ somewhat from those in children. The most common foods to cause allergies in adults are shrimp, lobster, crab, and other shellfish; peanuts (one of the chief foods responsible for severe anaphylaxis); walnuts and other tree nuts; fish; and eggs.
In children, eggs, milk, peanuts, soy and wheat are the main culprits. Children typically outgrow their allergies to milk, egg, soy and wheat, while allergies to peanuts, tree nuts, fish and shrimp usually are not outgrown.
Adults usually do not lose their allergies.
The only way to treat food allergies is to avoid the foods that trigger reactions. Even the most diligent label-readers and ingredient-checkers likely will be inadvertently exposed to proteins that elicit an allergic response at some point.
Anaphylactic allergic reactions can be fatal even when they begin with mild symptoms such as a tingling in the mouth and throat or gastrointestinal discomfort. Antihistamines and bronchodilators can be used to treat less severe symptoms.
- What are the symptoms of an anaphylactic reaction?
- An anaphylactic reaction may begin with a tingling sensation, itching,
or metallic taste in the mouth. Other symptoms can include hives, a
sensation of warmth, asthma symptoms, swelling of the mouth and throat
area, difficulty breathing, vomiting, diarrhea, cramping, a drop in
blood pressure, and loss of consciousness. These symptoms may begin in
as little as five to 15 minutes to up to two hours after exposure to the
allergen, but life-threatening reactions may progress over hours.
What are the symptoms?
swelling of throat and mouth difficulty in swallowing or speaking
alterations in heart rate
difficulty breathing - due to severe asthma or throat swelling
hives anywhere on the body, especially large hives
generalised flushing of the skin
abdominal cramps, nausea and vomiting
sudden feeling of weakness (drop in blood pressure)
sense of impending doom
collapse and unconsciousness
Nobody would necessarily experience all of these symptoms. Some people find that the symptoms they experience are always mild. For example, there may be a tingling or itching in the mouth - nothing more. This is not serious in itself, and may be treated with oral antihistamines. Nevertheless, it is wise in all cases to make an appointment with the doctor and seek a referral to a specialist allergy clinic.
If there is marked difficulty in breathing or swallowing, and/or a sudden weakness or floppiness, regard these as serious symptoms requiring immediate treatment.
How can you tell if someone is having anaphylaxis?
Anaphylaxis usually happens quickly.Anaphylaxis can produce:
An itchy nettlerash (urticaria, hives) Faintness and unconsciousness due to very low blood pressure. Unlike an ordinary fainting attack, this does not improve so dramatically on lying down. Swelling (angioedema) Swelling in the throat, causing difficulty in swallowing or breathing Asthma symptoms Vomiting Cramping tummy pains Diarrhoea A tingling feeling in the lips or mouth if the cause was a food such as nuts Death due to obstruction to breathing or extreme low blood pressure (anaphylactic shock) Faintness with a rash or swelling coming on quickly is probably anaphylaxis, and if there is also difficulty in breathing the danger is greater. Faintness with difficulty in breathing alone will sometimes be due to a panic attack, but can also be due to anaphylaxis.
In the early stages it may be difficult, even for a doctor, to be sure whether the cause of symptoms is anaphylaxis or fainting or a panic attack. If there is doubt, it is sometimes best to use the treatment for anaphylaxis, but the treatment should then be reviewed with a doctor because unnecessary treatment for anaphylaxis is a bad idea. Learn the rules for knowing when to treat, to minimise the chance that you will use the treatment when you should not.
Fainting and Anaphylaxis: clues which may help you tell the difference
(this guide is not perfect; you need a doctor if in doubt.)AnaphylaxisFaintingColourPink, typicallyPale, typicallyPulseFast, usuallySlow, usuallyBlood pressureCan remain low lying downNormal when lying downOther features which may be presentNettlerash
Swelling
Difficulty breathing
Tummy pain or diarrhoeaThe person has probably fainted before.
(Some people do faint, others don't.)
The fact that previous anaphylaxis has been mild does not guarantee that it will not be dangerous in future. Most sufferers with mild attacks do seem to have relatively mild ones if they occur again. But deaths have occurred in people who had only mild attacks before. The answer is to be prepared.
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