Allergies can cause vastly different arrays of symptoms, depending on the exact triggers causing the allergic reaction, the severity of the condition and personal susceptibility. Those struggling with allergies might experience just one or several symptoms during each allergic reaction – some of the symptoms might be very mild and easy to handle with proper treatment, while others might begin to significantly impact the quality of life of those affected, even requiring medical attention.

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Naturally, the exact nature and severity of symptoms will mostly depend on the exact type of allergy you have. For example, while airborne allergens mostly cause respiratory and ocular problems, contact allergies will tend to result in symptoms affecting the skin such as rash or hives. Finally, food allergies and allergic reactions to different drugs can cause a number of different symptoms, both within the gastrointestinal track and on the outside of the body.

In this article, we will take a look at the a number of most common symptoms and clusters of symptoms.

Allergic rhinitis

One of the most common allergic conditions in the UK, allergic rhinitis will cause the characteristic inflammation of the nasal passages, resulting in flu-like symptoms including sneezing, itchy nose, excess mucus production and blocked airways. While these symptoms aren’t dangerous, they can be rather uncomfortable and frustrating to handle.

The severity of this condition is very varied among individuals, but it can usually be successfully managed with the use of antihistamines or decongestants. Prescription medicines will be recommended by the doctor if the condition starts to affect the quality of life, for example, by disrupting sleep patterns.

Breathing difficulties

Breathing difficulties occur when the airways become obstructed due to the characteristic swelling, making breathing increasingly difficult. As a result, an individual might experience symptoms such as coughing, wheezing, chest tightness and shortness of breath – all of these might seem frightening for people experiencing them, but it is not without reason. So-called allergic asthma should definitely be discussed with a medical professional as it might require the use of preventive or reliever inhalers, usually based on either corticosteroids or beta-2 agonists that are used to prevent an exacerbation or calm the inflamed airways and facilitate easier breathing, respectively.

Allergic conjunctivitis

The cluster of symptoms usually designated as allergic conjunctivitis affects the eyes, causing them to become red, itchy and excessively watery. During conjunctivitis flare up, the front layer of the eye (called conjunctiva, hence the name of the condition) will become inflamed and irritated. Most commonly, allergic conjunctivitis will be treated with antihistamine eye drops.


Eczema is a skin reaction that occurs as a symptom of numerous types of allergic reactions, including food and medicine allergies as well as contact allergies, of course. It is characterised by excessive dryness and inflammation of the skin. These irritations can cause an itchy sensation, causing the person affected to scratch and potentially injure the skin, thus increasing the risk of a secondary infection.

Dermatitis also commonly occurs as a first symptom of contact allergies like allergy to nickel, hair dye or latex.

Abdominal discomfort and indigestion

Another cluster of potential symptoms related to food allergies include stomach pain, diarrhoea, nausea and vomiting. Gastric problems of this kind can occur if the histamine is released and directed to that specific area of the body which can occur if the allergen has been introduced through the gastrointestinal tract, which is the case with food allergies and most drug allergies.

Hives and rash

Some allergies can cause rather prominent skin reactions, most commonly in the form of the rash known as urticarial or hives. The affected area of the skin will be covered by patches of varying sizes that are itchy and raised. In most cases, hives will disappear as soon as the allergen is removed from the system, but in some cases, the rash might remain, requiring the use of antihistamines or orally administered corticosteroids.


As the allergic reaction progresses, numerous areas of the body can become swollen. Called angioedema in the medical community, swelling caused by allergies can affect the face, lips, genitals, hands or feet, commonly in parallel with urticarial outbreak. In majority of cases, the swelling will pass on its own, but in certain especially severe cases, antihistamines or steroids will have to be administered.


Certainly the single most dangerous symptom of an allergic reaction, anaphylaxis will occur once the person affected goes into anaphylactic shock, a life-threatening condition during which the airways will become so narrowed that breathing becomes almost impossible. The person affected will usually experience a sudden feeling of weakness and signs of fainting, as the dramatic blood pressure drop occurs.

People experiencing anaphylaxis must receive urgent medical attention – in a majority of cases, it will involve administration of adrenaline directly into the body via an injection (adrenaline auto-injector device), commonly known as Epipen. Epipens are designed to allow quick administration of adrenaline into the body, so that the hormone can in turn instantly relax airway muscles, allowing the person affected to breathe again. In addition to this, adrenaline will also increase the dangerously low blood pressure.

People who might be at risk of experiencing a severe allergic reaction should get the appropriate treatment in order to prevent anaphylactic shock. And if their condition is very severe and the risk of anaphylaxis remains high despite treatment, an Epipen might be prescribed to ensure you remain safe wherever you are. In any case, if you are struggling with severe allergic reactions, you should definitely consult with a doctor so you can devise the most suitable allergy management plan.