Allergies are abnormal reactions of the immune system that occur in response to otherwise harmless substances.

An Allergy is a type of immune reaction. Normally, the immune system responds to foreign microorganisms or particles by producing specific proteins called antibodies. These antibodies are capable of binding to identifying molecules, or antigens, on the foreign particle. This reaction between antibody and antigen sets off a series of chemical reactions designed to protect the body from infection. Sometimes, this same series of reactions is triggered by harmless, everyday substances such as pollen, dust, and animal dander’s. When this occurs, an allergy develops against the offending substance (an allergen). A substance that provokes an allergic response is called Allergen.

Types of Allergies

There are many different forms of Allergies, ranging from food and pollen to drugs and chemicals to insects and dust mites, a variety of symptoms, triggers and treatment options accompany them. Your first step in getting relief is to understand what’s causing your particular reactions. Some of the common allergies are:-

• Hay fever.
• Conjunctivitis (inflammation of the tissue that lines the eyelid).
• Asthma.
• Eczema. Eczema is sometimes called atopic dermatitis because it is a hypersensitivity Allergic reaction that affects a part of the body that is not in direct contact with the allergen.
• Sneezing,
• Wheezing,
• Coughing
• Skin rashes.

  

Causes of Allergy

The immune system normally protects the body against injurious substances, such as bacteria and viruses. It also reacts to alien substances called allergens, which are generally harmless and in most people do not cause a problem. But in a person with allergies, the immune response is oversensitive. When it recognizes an allergen, it releases chemicals such as histamines that fight off the allergen, this causes allergy symptoms. Common allergens include:

• Drugs
• Dust
• Food
• Insect bites
• Mold
• Pet dander
• Pollen

Symptoms of Allergy

• Skin.  Allergens that touch the skin can cause redness, itching, bumps or wheals, crusting, weeping patches, blisters.
• Respiratory Tract.  Allergens that you breathe often cause wheezing, sneezing, coughing, difficulty in breathing
• Stuffy or Runny Nose.
• Digestive Tract.  Eating something you are allergic to can cause nausea, vomiting, diarrhea, stomach cramps.
• Eyes. Allergens that touch the eyes may cause Itching, watering, bloodshot or puffy appearance.
• Other. Headache, dizziness, ringing in the ears.
• Drug allergiesusually involve the whole body and can lead to a variety of symptoms

  

Treatment of Allergies

The best way to reduce symptoms is to avoid what causes your allergies. This is especially important for food and drug allergies. There are several types of medications to prevent and treat allergies. Illnesses that are caused by allergies (such as asthma, hay fever, and eczema) may need other treatments. Medications that can be used to treat allergies include:

1. Antihistamines. Antihistamines are available over-the-counter and by prescription. They are available in many forms, including:-

• Capsules and pills
• Eye drops
• Injection
• Liquid
• Nasal spray

1. Corticosteroids. Anti-inflammatory medications (corticosteroids) are available in many forms, including:-

• Creams and ointment for the skin
• Eye drops
• Nasal spray
• Lung inhaler

Patients with severe allergic symptoms may be prescribed corticosteroid pills or injections for short periods of time.

1. Decongestants.  Decongestants can help relieve a stuffy nose. Do not use decongestant nasal spray for more than several days, because they can cause a “rebound” effect and make the congestion worse. Decongestants in pill form do not cause this problem. People with high blood pressure, heart problems, or prostate enlargement should use decongestants with caution.
2. Other Medicines. Leukotriene inhibitors are medicines that block the substances that trigger allergies. Zafirlukast (Accolate) and montelukast (Singulair) are approved for people with asthma and indoor and outdoor allergies.
3. Allergy Shots. Allergy shots (immunotherapy) are sometimes recommended if you cannot avoid the allergen and your symptoms are hard to control. Allergy Shots keep your body from over-reacting to the allergen. You will get regular injections of the allergen. Each dose is slightly larger than the last dose until a maximum dose is reached. These shots do not work for everybody and you will have to visit the doctor often.

Severe Allergic Reactions (anaphylaxis) need to be treated with a medicine called Epinephrine, which can be life saving when given right away. After administration of this medicine, straight away go to the hospital.

CAUTION: NEVER USE DRUGS WITHOUT PRESCRIPTION OF A DOCTOR

 

Difference between Allergy, Sensitivity and Intolerance

Allergy.  Allergy is a reaction produced by the body’s immune system when it encounters a normally harmless substance.

Sensitivity.   Sensitivity is the exaggeration of a normal side effect produced by contact with a substance. For example, the caffeine in a cup of coffee may cause extreme symptoms, such as palpitations and trembling, when it would usually only has this effect when taken in much larger doses.

Intolerance.  Intolerance is where a substance (such as lactose) causes unpleasant symptoms (such as diarrhoea) for a variety of reasons, but does not involve the immune system. People with intolerance to certain foods can typically eat a small amount without having any problems. In contrast, people with a food allergy will have a bad reaction even if they come into contact with a tiny amount of the food to which they are allergic.

 

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