An allergy is the response of the body's immune system to normally harmless substances, such as pollens, foods, and house dust mite. Whilst in most people these substances (allergens) pose no problem, in allergic individuals their immune system identifies them as a’ threat’ and produces an inappropriate response.
The most common causes of allergic reactions are:
- pollen from trees and grasses
- proteins secreted from house dust mites
- foods such as peanuts, tree nuts, milk and eggs
- pets such as cats and dogs, and other furry or hairy animals such as horses, rabbits and guinea pigs
- insects such as wasps and bees
- medicines (these may cause reactions by binding to proteins in the blood, which then trigger the reaction)
What Happens When You Have an Allergic Reaction?
When a person comes into contact with a particular allergen they are allergic to, a reaction occurs. This begins when the allergen (for example, pollen) enters the body, triggering an antibody response. When the allergen comes into contact with the antibodies, these cells respond by releasing certain substances, one of which is called histamine. These substances cause swelling, inflammation and itching of the surrounding tissues, which is extremely irritating and uncomfortable.
Common symptoms associated with allergic conditions include:
- wheezing / coughing / shortness of breath
- sinus pain / runny nose
- nettle rash / hives
- itchy eyes, ears, lips throat and mouth
- sickness, vomiting & diarrhoea
How to Help Your Doctor Diagnose an Allergy
The first step in managing an allergy is identifying the cause(s) of the problem. Diagnosing allergy can be difficult since the symptoms may be similar to other conditions. You may be referred by your GP to a specialist allergy service and our helpline can tell you where your nearest specialist clinic is and give you details to take to your GP. If you think you may be allergic to something and do not know what it is, you should start to keep a record of your symptoms. In particular, the following information may help your doctor make a diagnosis
- Do they occur at any particular time of the day?
- Do you only get symptoms at certain times of the year?
- Do you suffer more at night time or during the day?
- Do your symptoms occur when you are in the house as well as outside?
- Does exposure to animals bring on your symptoms?
- Do you think that any food or drink brings on your symptoms?
- Do the symptoms occur every time you come into contact with the allergen?
- Do your symptoms improve when you are on holiday?
How Do I Manage My Allergy?
You can find specific information on a range of allergies on our website but here are 3 key things to remember when it comes to managing your allergy:
- Documenting where and when a reaction occurs
- Reducing the risk of an allergic reaction by avoiding the allergen, wherever possible.
- Medical treatments to reduce symptoms including medications and immunotherapy.
For more detailed information about allergy please find further useful resources below…
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