Allergies And Anaphylaxis Symptoms

Adult and child


Anaphylaxis is pronounced anna-fill-axis. This is the most serious reaction to an allergen; the symptoms onset is quick and could be life threatening. Fatalities are rare but anaphylaxis must be treated seriously and seek medical attention immediately. In most people two or more systems are involved.

A food allergy can be life threatening; a food intolerance is where your body has a problem digesting a food, a food intolerance is not life threatening.

Sometimes, anaphylaxis can occur when there is no known trigger. This is referred to as ‘idiopathic anaphylaxis’.

Signs and symptoms

An allergic reaction can cause symptoms within minutes to exposure of an allergen, in some cases it can vary and can be several hours after exposure, this is because the mouth and throat are still absorbing the food which has the allergen present.

In every person the reaction can be different, anaphylaxis normally include 2 or more of the symptoms below, also anaphylaxis can occur without hives. Always act quickly from onset of first symptoms.

Antihistamines can help with hives, stop itching, but they cannot stop anaphylaxis, if having anaphylactic symptoms use adrenaline auto-injector first before taking any other medications.

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Hives (urticaria) anywhere on the body 
Swelling (face, lips, tongue) – this is called angioedema, and other parts of the body can swell. There could be difficulty in speaking due to swelling.
Warmth, skin hot to touch, or feels clammy.
Pale or blue colouring of the skin


Coughing, wheezing, shortness of breath, chest pain or tightness, feeling of burning in chest area, severe asthma, fast and shallow breathing, laboured, noisy breathing.
Throat tightness (problems with swallowing), hoarse voice, there could be difficulties with speaking.
Nasal congestion or hay fever-like symptoms, (runny, itchy nose and watery eyes, sneezing) Nasal congestion could cause breathing through nose restricted.


Pain or cramps (Pain can vary in severity)
Diarrhoea and can be acidic


Cardiac arrest

Paler than normal skin colour/blue colour
Weak pulse
Passing out, dizziness or light-headedness, loss of consciousness (in extreme cases) confusion
Low blood pressure
Pounding heart, heart rate increased.


Anxiety, sense of doom (the feeling that something bad is about to happen), disorientation, confusion, distress, clumsiness, or panic.
Uterine cramps
Swelling of eyes, eyes maybe difficult to open due severity of swelling. Eyes could be reddened.
Metallic taste
Pain in inner ears
Sores on tongue
Itching mouth
Sore mouth 
Tingling lips, tingling tongue, tingling mouth
Angioedema may occur in the face, tongue, larynx, abdomen, or arms and legs
Floppiness in a child
Urinary urgency, or incontinence

Please note a child might have different symptoms to an adult, also they might use different language.

  1. Pulling or scratching at their tongue
  2. Placing their hands in their mouths
  3. If they can talk, their words maybe slurred or understandable.
  4. They might say my throat feels funny.
  5. Their tongue feels funny.
  6. Change in the voice tone.
  7. I don’t feel well.
  8. My tummy hurts
  9. I feel itchy
  10. My eyes are sore
  11. My ears are sore
  12. My lips feel funny
  13. My mouth feels funny
  14. The food doesn’t taste good

Symptoms in babies up to 2 years of age

Change in the sound of their cry
Spitting up of food or drink after feeding
Uncontrolled passing of stool or urine
Very sleepy or difficult to wake up
Appear very frightened
Upset want to be held or comforted
Change in the sound of their cry
Spitting up of food or drink after feeding
Uncontrolled passing of stool or urine
Very sleepy or difficult to wake up
Appear very frightened
Upset want to be held or comforted

Please note not all symptoms can be present and some people will react differently, always seek medical attention.

Not All Reactions Are the Same!
Past reactions do not predict future reactions!

People with certain health conditions are more likely to have severe allergic reactions, such as asthma.

There are certain situations that can make a reaction more severe such as:

Larger the dose of allergen or if allergen is within another food.
The situation that the person was exposed to the allergen
Exercise can affect either before or after consuming food
Travel such as flying as allergen is in air conditioning (airborne allergen)
If the person has consumed alcohol
The body can also react differently if unwell, experiencing anxiety, experiencing stress, hormones in the body can affect severity. (Menstrual cycle)
Some medications e.g., beta-blockers, ACE inhibitors, non-steroidal anti-inflammatory medication (NSAIDs) e.g., ibuprofen, may interfere with the action of adrenaline auto-injector and worsen the allergic reaction.

What is a Biphasic Reaction?

An anaphylactic event can happen in 2 stages, this means after the initial anaphylaxis is treated and symptoms has disappeared, they return without you being exposed to the allergen again. The second reaction can occur between up to 2-72 hours after the first reaction. Therefore, it is important to have a 2nd adrenaline auto-injector as it may be required for the 2nd reaction.

Increased risk factor for having a second reaction.

The patient is a child
A delay in receiving treatment or a delay in administering adrenaline auto-injector pen of greater than 90 minutes after the symptoms first appear.
More than one dose of adrenaline auto-injector pen is required.
Respiratory symptoms require a dose of inhaled salbutamol. (Ventolin)

Individual Food Allergy And Anaphylaxis Action Plan

Advisable to have with anyone caring for your child, your workplace, places you go often for example clubs/meetings to have an emergency action plan, ask your doctor or consultant for an action plan.

This information is only given as guidance and not extensive. Information to be used at individual’s responsibility.  Always seek medical advice.

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