Aggressive allergens
Aggressive allergens are those more likely to cause symptoms in a patient, because the body reacts to them in a more intense way. Some allergens are simply more aggressive than others, where a smaller amount is needed to trigger an allergic reaction. Some allergens can be made more aggressive by interaction with the environment, as is the case with pollens affected by air pollution.
Allergic disease
The term ‘allergic disease' refers to a group of medical conditions that are experienced as a result of an allergic reaction; these include allergic rhinitis, allergic rhinoconjunctivitis, allergic asthma, allergic dermatitis, food allergy, urticaria and atopic eczema.
Allergic reaction
An allergic reaction is experienced when the body attacks something that it should not normally attack. By-products of this immune system response are allergic symptoms, such as a runny or blocked nose, watery and itchy eyes, or severe itching of the skin. Experiencing these symptoms is commonly referred to as an ‘allergic reaction'.
Allergic rhinitis
Allergic rhinitis is the medical term for symptoms of the nose experienced as a result of the immune system being oversensitive to a given allergen. Hayfever can be considered a type of allergic rhinitis but allergens that cause allergic rhinitis can come from both indoor and outdoor environments, such as house dust mites and pollen. The symptoms of allergic rhinitis may be experienced all year round. This can be explained due to the diverse range of allergens that can cause allergic rhinitis and other allergic symptoms.
Allergy medication
Some allergy medications simply ease the symptoms of an allergic reaction whereas others address the root cause of the symptoms, namely, the body's release of excess histamine. Some common medications available to reduce allergic symptoms are:
- decongestants
- antihistamines (as tablets, nasal sprays or eye drops)
- intranasal corticosteroid spray
Patients suffering from allergic symptoms should seek advice from healthcare professionals to decide on the best allergy medication to treat their symptoms.
Allergy protective bedding
Allergy protective bedding is designed to reduce an individual's likelihood of suffering an allergic reaction. It is thought that by reducing contact with house dust mite faeces, a common cause of allergy, allergy protective bedding may reduce allergic symptoms caused by this allergen.
Allergy symptoms
Allergy symptoms are physical symptoms experienced as a result of the immune system “over reacting” to exposure to a given allergen(s). Allergy symptoms are often likened to those of cold and flu. Allergy symptoms include repeated sneezing; blocked, runny or itchy nose; watery and itchy, or sore and swollen eyes; distorted sense of smell or taste and difficulty breathing. These types of allergy symptoms are referred to as allergic rhinitis or rhinoconjunctivitis, which includes hayfever. Other allergy symptoms include difficulty sleeping and tiredness during the day. Some allergy sufferers will be polysymptomatic and may also suffer from additional atopic disorders such as allergic asthma, allergic dermatitis, allergic eczema and urticaria.
Allergy triggers
An allergy trigger is an external factor that can increase or exacerbate a person's likelihood of experiencing an allergic reaction when exposed to an allergen. As such, an allergy trigger amplifies the effect of an allergen. Examples of triggers include tobacco smoke, indoor or outdoor pollution, and psychological stress.
Anaphylaxis
Anaphylaxis is the most severe type of allergic reaction. It is a systemic allergic reaction. Anaphylaxis may start by swelling of the mouth, tongue, lips, skin and eyelids. In serious cases, an anaphylactic episode progresses to vomiting, wheezing, breathing difficulties and even cardiovascular collapse. If not treated promptly, anaphylactic reactions may be fatal.
Antihistamine treatment
Antihistamines are an effective treatment available for the symptoms of an allergic reaction. During an allergic reaction, histamine is released. Histamine particles bind with histamine receptors, which directly cause allergic symptoms and initiates allergic inflammation. Antihistamine treatment interrupts the binding of histamine particles to receptors and as such, reduces the impact of an allergic reaction.
Blood test
Over 400 different allergens may be tested by measuring the amount of specific Immunoglobulin E antibodies (IgE) in your blood to various environmental and food allergens.
Challenge test
Challenge tests are conducted in hospital, by introducing a suspected allergen directly into the nose, lung or eye, or orally, to see if it can provoke an allergic reaction that can then be measured.
Exotic fruit
Exotic fruits that have become available in countries where they do not naturally grow have contributed to the increase in allergic reactions across Europe. It is thought that exotic fruit allergies are experienced due to the body's lack of exposure to such food compounds. Due to this lack of familiarity, the body believes that the exotic fruit is a threatening substance and hence issues an immune system response against it.
Food allergy
A food allergy is an immune system response to a food type that the body believes is harmful. Once this food type has mistakenly been identified as an “invader”, the immune system creates antibodies to attack it. Subsequent consumption of the food type results in the antibodies causing the release of a number of mediators, including histamine.
Hayfever
Hayfever is a term that is used to describe the symptoms of allergic rhinitis. However, the term hayfever specifically refers to allergic reactions due to pollen. Pollen is the male reproductive part of plants and trees. Hayfever is experienced when these pollen particles come into contact with the inside of the nose of an individual allergic to pollen.
Occupational allergens
Occupational allergens are those allergens that we become sensitised to in the workplace. Work-related sneezing and nasal discharge may alert one to possible occupational allergens. There are also a lot of work-related dermatological allergies affecting the skin. Individuals such as nurses, hairdressers, printers, clothes manufacturers and florists are particularly likely to be affected by occupational allergens.
Patch test
This test is used to diagnose delayed allergic reactions such as contact dermatitis. Allergy to rubber, nickel, lanolin, dyes, and cosmetics, certain types of medications, solvents and preservatives may be identified this way.
Pollen screens
Pollen screens have been developed in an attempt to reduce the impact of pollen upon individuals who are allergic to it. Pollen screens are designed to stop pollen entering a room by acting as a filter.
Skin allergies
Skin allergies are reactions caused by substances that come into contact with the skin. Atopic dermatitis, allergic eczema, and urticaria, or hives, are types of skin allergies.
Skin-prick test (SPT)
These are conducted by pricking the skin with a needle across a drop of a known allergen. A positive reaction occurs when the skin around the needle prick becomes itchy and red, developing into a white swelling called a wheal, which reaches its peak after 15-20 minutes.