Allergies can cause lots of different symptoms, and those who living with an allergic condition may experience several or just one.

Some may only notice mild symptoms and they feel they can cope without treatment; whereas others may encounter symptoms to an extent which affects their quality of life, and warrants medical attention.

Symptoms largely depend on the type of allergy you have. Airborne allergens tend to cause respiratory and ocular reactions; those allergens which come into contact with the skin may result in skin symptoms; and ingested allergens such as food and drugs may cause a range of internal and external effects.

You can read more on the causes of allergies on our information page.

Here are some of the more common symptoms of allergic conditions explained in more detail:

Allergic rhinitis

This is one of the most common allergic reactions in the UK. It results in inflamed nasal passages causing flu-like symptoms such as sneezing, an itchy nose, excess mucus or a blocked airways; all of which can be considerably frustrating to deal with.

The severity of rhinitis can vary greatly. Those who experience this type of reaction can control their symptoms with antihistamines or decongestants in most cases, however worsened cases can disrupt sleeping patterns and start to impinge on quality of life.

Breathing difficulties

A consequence of the airways becoming constricted due to swelling is a reduced capacity to breathe.

This can cause coughing, wheezing, chest tightness and breathlessness. These symptoms might be prevalent in the morning or at nighttime, potentially disturbing sleep.

Experiencing breathing problems due to an allergic reaction can be scary. The symptoms should be taken seriously and discussed with a medical professional.

Allergic asthma can be effectively treated with both preventative and relief-offering inhalers. The majority of inhalers contain either corticosteroids or beta-2 agonists that work to either prevent a reaction from happening or calm inflamed airways during a reaction.

Allergic conjunctivitis

This symptom presents itself through red, itchy and excessively runny eyes. The front layer of the eye known as the conjunctiva becomes inflamed and irritated.

Antihistamine eye drop treatments can be used to directly treat the cause and soothe the eye.


This skin reaction can occur when certain foods are ingested, medications are taken or the skin directly touches an irritant substance. The skin can become extremely dry and inflamed which can also be painful.

Irritated skin can also provoke the person to scratch the area which can lead to infections if the skin is broken.

Skin infections should be prevented as much as possible as they can be problematic to treat and take longer to recover from.

Dermatitis can also be a result of the skin coming into direct contact with an allergy substance. Common triggers include nickel, hair dye and latex.

Abdominal discomfort

Gastric problems can occur if the immune system releases the chemical histamine into that area of the body.

If this reaction takes place in the gut the person might experience stomach pain, diarrhoea, nausea or vomiting.


Allergies can sometimes cause a rash to form on areas of the body, known clinically as urticaria. The patch or patches can be small and limited to one area or be much bigger and take over large portions of the body.

The itchy, raised rash may calm down once the trigger allergen is removed or passes through the system. However, in some cases the rash may need to be treated with antihistamines or oral corticosteroids.


Areas of the body can become swollen during and following on from an allergic reaction.

Known medically as angioedema, the condition tends to affect the face, lips, genitals, hands and feet. This reaction is often seen in conjunction with urticaria.

For many, the symptoms will dissipate without the need for treatment. However, there are some people who will require treatment with either antihistamines or steroids.


Severe allergies can result in life threatening situations where the person goes into anaphylactic shock.

During this, the airways become extremely constricted making it very difficult for the person to breathe. Another common sign of anaphylaxis is a sudden feeling of weakness or collapse caused by a dramatic drop in blood pressure.

It is very important for those who experience anaphylaxis to receive urgent medical attention. People at risk of anaphylactic episodes and those who have experienced severe allergies in the past are frequently prescribed with an adrenaline auto-injector device often referred to as an Epipen.

These devices allow for the quick administration of adrenaline into the body. The adrenaline contained therein enters the system and works fast to relax airway muscles, improving breathing and increasing dangerously low blood pressure.

It is important to get the appropriate treatment for your allergy condition. If you notice symptoms similar to those listed above then you should see your doctor. They may wish to send you for allergy testing as the results will help them to come up with the most suitable allergy management plan.

Page last reviewed:  17/05/2016