Hay fever allergies

HAY FEVER ALLERGIES

Hay fever, also called allergic rhinitis, causes cold symptoms and signs like a runny nose, congestion, sneezing and sinus pressure. But unlike a cold, hay fever is not caused by a virus. Hay fever is caused by an allergic reaction to indoor allergens and outdoor allergens , such as pollen, dust mites or animal dander. Hay fever is common - affecting more than 1 in 5. Some people have symptoms all year round. For others, the symptoms of hay fever worse at certain times of year, usually in spring, summer or autumn. Hay fever can make you miserable and affect your performance at work or school, and interfere with recreation. But you do not have to endure the annoying symptoms. Learning to avoid triggers and find the right treatment can make a big difference.

CAUSES
Causes of hay fever If you have hay fever, contact with pollen or mold spores or fungi to produce a system, called immunoglobulin E (IgE). Antibodies are usually only released to fight infection, but in this case, the body believes is harmful to pollen. This affects the immune system fireworks is a fuse, trigger the release of certain chemicals in the cells of the nose, throat and eyes, when a lot of pollen. One of these chemicals is histamine  , that cause symptoms of hay fever.
You may be allergic to one or more types of pollen .This determines when symptoms are severe.

Possible causes are :

Grass pollen -   half the adults in the United Kingdom, who have hay fever are allergic to grass pollen, and the varieties that are more responsible for the ryegrass and Timothy ,.
Tree pollen - one of every four people in the UK with hay fever are allergic to birch pollen, but different trees produce pollen at different times of year, it depends on what you are allergic to when your symptoms are worst .
Weeds  - such as ragwort and other plants, and fungi and mold spores

SYMPTOMS
Symptoms of hay fever usually begin as soon as it is exposed to substances that cause allergies (allergens) and may include:

• A runny nose and eyes.
• Nasal congestion.
• Watery and itchy nose, scratchy palate or throat.
• Sinus pressure and facial pain.
• Swelling, skin color with blue under eyes  (eye allergies).
• Decreased smell or taste.
• The symptoms of hay fever can begin or worsen a particular time of year triggered by tree pollen, grasses or weeds, which flourish at different times. If you’re sensitive to indoor allergens such as dust mites, cockroaches, mold or pet hair, you may have symptoms all year round. Many people have allergy symptoms all year, but their symptoms worsen at certain times of the year.

DIAGNOSTIC INVESTIGATIONS
Examination and tests  :

Your doctor will ask the following:

• Medical history, including allergies, asthma, eczema .
• Seasonal symptoms associated with certain geographic areas .
• Family history of hay fever, asthma or anyother allergies .
• He or she can take a drop of runny nose, look under a microscope for many immune cells called eosinophils, which increase greatly in number during an allergic reaction.
• An specialist for allergy (allergist) may be able to determine the exact allergen is causing your hay fever. He or she uses a skin test in which dilute solutions of different allergens are introduced into the skin. A positive reaction is indicated by a typical wheal and flare reaction (a red bump).