What is anaphylaxis?

Everything you need to know about the triggers, symptoms, misconceptions and diagnosis 

Anaphylaxis is a severe, potentially life-threatening allergic reaction occurring within seconds or minutes following exposure to an allergen, such as peanut or the venom from a bee sting.

It typically involves more than one system of the body and can be fatal if not treated immediately. Warning signs may include:

• Urticarial rash;
• Swelling of areas of the body or the throat;
• Wheezing;
• Loss of consciousness;
• Difficulty breathing;
• A hoarse voice;
• Vomiting;
• Diarrhoea;
• Stomach cramps;
• Redness or pallor of the skin.

Common anaphylaxis triggers include certain medications, especially anti-inflammatories, penicillin, and some foods such as peanuts and shellfish, and bee stings. Latex, anaesthetics and even physical exercise could be possible triggers but are far less common.

Determining the cause

If you’ve experienced anaphylaxis and are not sure what triggered it, a thorough history and clinical examination will need to be taken to get to the bottom of your reaction. This may include questions about the food or medicines consumed before your severe reaction and exposure to insects.

The medical examination is also necessary to eliminate possible conditions that are sometimes confused with anaphylaxis, such as fainting or an epileptic seizure or uncontrolled asthma and chronic urticaria.

If an allergy is suspected, this may be followed by allergy tests, which usually entails a blood test for allergen-specific IgE or skin prick testing to help confirm or exclude potential triggers.

Allergy testing must be done 4-6 weeks after acute anaphylaxis to prevent false negatives. Skin prick tests must be done with extreme caution in patients with a history of anaphylaxis.

Regular follow up to review the diagnosis as well as reviewing risk factors, and your personalised action plan all contribute to keeping allergic patients safe.

Co-factors for anaphylaxis

Co-factors for anaphylaxis are factors that can contribute to the severity and likelihood of anaphylaxis. These include infections, exercise, medications such as anti-inflammatories and ACE-inhibitors taken with a beta blocker, as well as blood pressure medication. Uncontrolled asthma, cardiovascular disease, COPD, menstruation all are recognised as co-factors that increases the risk as well as the severity of anaphylaxis.

Emergency treatment

The primary management of anaphylaxis is allergen avoidance as well as being prepared for an emergency. Auto-Injectable epinephrine (adrenaline – also referred to as EpiPens) should be readily accessible to people who have had previous anaphylaxis or suffer from a severe allergy such as peanut or shellfish allergy.

This is a single dose of medication that is injected into the thigh during an anaphylactic emergency.

Family members and colleagues should also be informed of the situation and be confident in using an EpiPen. Other medication needed in an acute emergency may include anti-histamines and an asthma inhaler.

The necessity of an action plan

An Anaphylaxis Action Plan should also be readily available at work, school or other places it may be necessary for other people to recognise the symptoms and provide life-saving treatment. The Anaphylaxis Action Plan should outline the specific treatment the patient requires in a simple, straight forward manner. Click here for an example of a thorough Anaphylaxis Action Plan. The Allergy Society of South Africa’s Anaphylaxis Action Plan also is a helpful resource.

In conclusion

Anaphylaxis is life-threatening, but with knowledge about avoiding the appropriate allergen, having a very clear action plan and adequate training can take the fear and uncertainty out of managing your anaphylaxis. Your healthcare provider must work closely with you to navigate this threat and the evolving challenges you might face.

Additional Reading:

• World Allergy Organization Guidelines for the Assessment and Management of Anaphylaxis
• A case study of anaphylaxis and its required treatment

(Photo by Kelly Sikkema on Unsplash)

© 2018 | Dr Marinda McDonald | Practice number 0015393 | All rights reserved

• The purpose of this article is to raise awareness of allergies and the treatment options that are available for it. This article should by no means be used, or viewed, as a primary source for medical advice – please arrange for a personal consultation with your medical practitioner before taking any decisions that could affect the wellbeing of you or your loved ones. Read our medical disclaimer for more information.