What is Anaphylaxis?

Key Takeaways on Anaphylaxis and Severe Allergic Reactions

• Anaphylaxis is a severe allergic reaction that can develop within minutes to two hours of allergen exposure, often escalating rapidly.

• Common causes of anaphylaxis include food allergies (e.g., peanuts, shellfish, eggs), insect stings, certain medications, latex, and even exercise.

• Mild allergy symptoms such as hives, swelling, and itching can quickly progress to life-threatening signs like difficulty breathing, shock, or collapse.

• Anaphylaxis symptoms to watch for include swelling of the tongue or throat, hoarse voice, wheezing, dizziness, rapid heartbeat, and loss of consciousness.

• Allergens can enter the body by ingestion, inhalation, injection (e.g., insect stings, medication), or absorption through the skin.

• First aid for anaphylaxis involves following DRS ABCD, laying the person flat (or upright if breathing is difficult), and administering adrenaline via an EpiPen.

• Call emergency services (000 or 112 in Australia) immediately after giving adrenaline and monitor the casualty’s airway, breathing, and circulation.

• Prevention of anaphylaxis includes avoiding known allergens, reading food labels, informing restaurants and caregivers, and considering allergy treatments like immunotherapy.

• Always carry an adrenaline autoinjector (EpiPen or Anapen) if prescribed, and ensure family, friends, and colleagues know where it is and how to use it.

• Training in anaphylaxis first aid through accredited courses, such as CPR First Aid training, improves preparedness and can save lives.

Anaphylaxis is a severe, sometimes sudden reaction to allergies. It can occur when a susceptible person is exposed to an allergen (such as food or an insect sting). It can strike in minutes—sometimes within 20 to 2 hours after contact with an allergen. It often starts subtly but can escalate dangerously fast. In rare cases, severe symptoms appear suddenly without warning signs of a milder allergic reaction.

Anaphylaxis is potentially life-threatening and always requires a medical emergency response.

Common Causes of Anaphylaxis:

• Food allergies, such as peanuts, shellfish, tree nuts, fish, lactose, eggs, wheat, seafood, fish, soy
• Insect stings, such as bees, wasps, or even ants
• Tick bites
• Some materials, such as latex
• Medications, both over-the-counter and prescribed, can cause life-threatening allergic reactions, e.g. aspirin and antibiotics such as penicillin.
• Some herbal remedies can also induce reactions
• Exercise
  

Mild to moderate reactions might begin with hives or an itchy rash. But don’t let your guard down—severe symptoms can follow swiftly, including life-threatening breathing difficulties or shock. Stay alert and act fast if you notice these warning signs!
Here’s what to watch for:

Soon after hives develop, more severe symptoms (Anaphylaxis) may occur, which indicate moderate allergic reactions, including:

• Shock
• Altered mental status
• Difficulty breathing, or shortness of breath and gasping
• The casualty may become very anxious and have a great sense of fear
• Respiratory or cardiac arrest and unconsciousness
• Difficulty and noisy breathing
• Swelling of the tongue
• Swelling or tightness in the throat
• Difficulty talking or having a hoarse voice
• Wheeze or persistent cough
• Loss of consciousness and collapse
• Pale and floppy (young children)

Disclaimer: The following first aid instructions are guidance only and should not replace professional medical advice or treatment.

What is an Allergy?

An allergy occurs when a person’s immune system reacts to triggers (allergens) that the person is hypersensitive to. These triggers are usually harmless to most people. Symptoms of an allergy can range from mild to potentially life-threatening (severe). An allergy occurs when the body mistakes something harmful and creates a defence system (antibodies) to fight it.

The ways allergens can enter the body:

• Ingested (most commonly, in the mouth)
• Inhaled (breathed in)
• Injected (bees, wasps, ants, or medication)
• Absorbed (through touching the skin)
• Allergy symptoms develop when the antibodies are battling the “invading” allergen.

Signs and Symptoms (Allergy):

• Initial signs (these can be used as warning signs to get help)
• It may begin with itchy hands, mouth, or feet
• Eyes may become red, watery, and puffy
• Tingly around the mouth
• Swollen lips and face
• Rash or hives (red welts) can develop, especially on the chest, armpits, and groin (hives are white, itchy bumps that look and feel like insect bites)
• Stomach pain, vomiting, diarrhoea
• Abdominal pain
• Vomiting

Management of an Allergic Reaction (Mild to Moderate):

• Follow DRS ABCD as required
• If you have an insect allergy, flick out the sting if it is visible. If you have a tick bite and there is no history of tick allergy, immediately remove the tick.
• If the casualty has a history of tick allergy, the tick must be killed where it is rather than removed.
• Apply a cold compress to the bite/sting site
• Stay with casualty and reassure
• Call for help. Get someone to contact Triple Zero / 112 for an ambulance in Australia.
• If prescribed, first aid for anaphylaxis should be given as noted on the Australian ASCIA Action Plan, which a health professional approves for the casualty.
  -First aid for an anaphylactic shock (drop in blood pressure) may require the injection of a prescribed dose of adrenaline (epinephrine) using Anapen or Epipen
  -E-training and face-to-face courses teach the proper usage of such injectors and the correct execution of other first-aid responses to severe allergies
• Continue to monitor the casualty for signs of anaphylaxis
• Contact parent/guardian or other emergency contacts

Management of Anaphylaxis (Severe Allergic Reaction)

Anaphylaxis is unpredictable. Symptoms may improve initially but can worsen suddenly. Even if the injection helps, getting to a hospital ensures proper care and prevents a recurrence.

Stay prepared, act quickly, and always prioritise safety. Here are some tips:

• Follow DRS ABCD
• Lay the casualty flat. If having difficulty breathing, sit them upright and try to calm them.
• If known and possible, remove the source of the allergy
• Bring the EpiPen to the casualty. Use the autoinjector (EpiPen) to inject adrenaline. Specific training is required (Note that EpiPens have been designed for use by anyone in an emergency as instructions are shown on the label)
• Call 000 / 112 for St John ambulance
• Continually monitor the casualty’s airways, breathing, and respiration, as a sudden change may occur, requiring resuscitation at any time. Ensure that the EpiPen has been administered before commencing CPR.
• Contact parent/guardian or other emergency contacts
• If available, further adrenaline doses may be given if there is no response after 5 minutes
• If uncertain whether it is asthma or anaphylaxis, give adrenaline autoinjector FIRST, then asthma reliever

EpiPen:

• An EpiPen is a small, hand-held, automatic injection device.
• It contains adrenaline and is injected into the fleshy part of the casualty’s thigh when experiencing an anaphylactic reaction.
• EpiPens are prescribed to people with known allergies, and they may be able to inject themselves or may need assistance from first aid.
• Note: Single use only

Child Green Auto-Injector (<20kg).
Adult Yellow Auto-Injector (>20kg)

Anaphylaxis Management Plan

Ensure that all patients prescribed an adrenaline autoinjector have an anaphylaxis management plan that includes the following:

• Referral to an appropriate specialist
• Identification of the relevant allergen(s)
• Education on avoiding allergen(s)
• An anaphylaxis action plan (see image)
• Appropriate follow-up and review
• Train patients to recognise the symptoms of anaphylaxis and how to use their adrenaline auto-injector correctly.

Parents should advise preschools or schools of their child’s adrenaline autoinjector prescription and provide a completed anaphylaxis action plan illustrating the prescribed device.

Some high-risk patients can be prescribed two adrenaline autoinjectors, but they must be of the same brand.

Advise patients to check the expiry date of their adrenaline auto-injector regularly.

The Australasian Society of Clinical Immunology and Allergy (ASCIA) website offers health information, fact sheets, and consumer anaphylaxis resources.

Note: Severe allergic reactions or anaphylaxis symptoms can occur without a history of known allergies. This situation should be treated as an emergency. An adrenaline Autoinjector should be administered, and an ambulance should be called if available. First aid should be provided until expert help arrives.

How Can I Prevent Anaphylaxis?

While you can’t eliminate the risk of anaphylaxis, being proactive can make all the difference. Whether you’re managing food allergies, medication sensitivities, or insect stings, these tips will help you minimise exposure and stay prepared for the unexpected.

Avoiding Triggers: Your First Line of Defense

 What is the best way to prevent anaphylaxis? Avoiding your known allergens. Here’s how:

Food Allergies:

• Read labels like a pro. Check every ingredient list—even for products you’ve bought before, as recipes can change.
• Speak up when dining out. Let restaurant staff know about your allergies and ask how dishes are prepared. Cross-contamination is a hidden danger!
• Keep caregivers in the loop. If your child has allergies, inform their school, teachers, or other caregivers.

Medication Allergies:

• Share your history. Always inform healthcare providers about your allergies to ensure they prescribe safe alternatives.
• Explore options. If no alternatives exist, ask your doctor about drug desensitisation treatments.

Insect Allergies:

• Stay vigilant outdoors. Avoid walking barefoot in grass, drinking from open cans, or wearing bright clothing and perfumes that attract insects.
• Consider immunotherapy. An allergist can provide venom immunotherapy to reduce your sensitivity to stings.

Always Be Prepared

Preparation is key to managing severe allergies. Follow these steps to stay ready:

• Carry your epinephrine injector everywhere. Make it a non-negotiable habit. If you have severe allergies, this simple step could save your life.
• Wear a medical ID bracelet. This can alert medical staff to your condition in an emergency if you can’t speak for yourself.
• Educate your support system. Let friends, family, coworkers, and caretakers know about your allergies and where to find your emergency medication.
• Complete an anaphylaxis first-aid course. Free resources, like ASCIA’s e-training, can help you and those around you be better prepared.

CONCLUSION

Anaphylaxis is a severe allergic reaction that can be deadly. Knowing the signs and symptoms is essential to get help immediately if someone experiences anaphylaxis. If you have an EpiPen, it’s also necessary to understand how to use it properly in an emergency. Ensure you have a plan for managing anaphylaxis in case of an emergency. Knowing what to do could save someone’s life. And you can learn the right skills and knowledge with any first aid course or some with CPR training at CPR First Aid.