Allergy Definition, types and treatment

What does Allergy mean?
Allergy is an immune response of your body to a certain allergen ( foreign substance ) like pollen, dust, pet dander. Then your immune system produces a proteins Antibodies against that certain allergen. By this antibodies our immune system defends us against foreign material and invaders that may be harmful to you.
So what happens when your immune system discovers and intruder ( Allergen ): your immune system will produce antibodies against that allergen result in histamine release by mast cells which with other immune mediators result in the symptoms of allergy

Seasonal Allergy Hay Fever

 

Allergy symptoms:
Allergy symptoms depends on which type of allergy you have. Allergy may affect your nasal passages, digestive system or your skin. Allergic reaction differ widely from mild itching to sever life threatening spasm of the respiratory passages and asphyxia.
Allergy symptoms by type of allergy:
Hay fever, also called allergic rhinitis, may cause:
•    Congestion
•    Itchy, runny nose
•    Itchy, watery or swollen eyes (conjunctivitis)
Atopic dermatitis, an allergic skin reaction also called eczema, may cause:
•    Itchy skin
•    Red skin
•    Flaking or peeling skin

Urticaria

A food allergy may cause:
•    Tingling mouth
•    Swelling of the lips, tongue, face or throat
•    Hives
•    Anaphylaxis
An insect sting allergy may produce:
•    A large area of swelling (edema) at the sting site
•    Itching
•    Cough, chest tightness, wheezing 
•    Anaphylaxis
A drug allergy may produce:
•    Hives
•    Itchy skin
•    Rash
•    Facial swelling
•    Wheezing
•    Anaphylaxis
Anaphylaxis
it is a severe allergic reaction known as anaphylaxis. Anaphylaxis is a life-threatening medical emergency, this reaction involves several of the body's organ systems and can cause you to go into shock. Signs and symptoms of anaphylaxis include:
•    Loss of consciousness
•    Lightheadedness
•    Severe shortness of breath
•    A rapid, weak pulse
•    Skin rash
•    Nausea and vomiting
•    Swelling airways, which can block breathing
Allergy treatment :
1-    First of all avoidance of the causative allergen.
2-    Symptomatic treatment: to relieve symptoms of allergy like nasal spary decongestant, antihistamines, cromolyn or even steroid in severe or resistant cases of allergy.
3-    Immunotherapy: if allergy not relieved via the previously mentioned methods or in cases of severe allergy
4-    Emergency treatment if Anaphylaxis

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