ALLERGIES

GOOD MORNING BOYS.
MARK YOUR ATTENDANCE FIRST!!

Today we will achieve the following LEARNING OUTCOMES :-

Students will be able to -

1. Define Allergy.
2. List the major Allergens .
3. Enumerate the Mechanism involved in our Immune system to  cause Allergy.
4. State the Treatment given for Allergy .


GENERAL INSTRUCTIONS :-

1. Write your notes in your register.
2. There are two YouTube video link shared with the blog . Kindly watch it before you start reading the Blog.

3. Complete the Home work task given today & email me your yesterday & today's homework at vcn@stcolumbas.edu.in latest by 8:00 pm.



LET'S BEGIN

Allergies

Your immune system usually protects you from pathogens and keeps you well. However, like any other body system, the immune system itself can develop problems. Sometimes it responds to harmless foreign substances as though they were pathogens. Sometimes it attacks the body’s own cells. Certain diseases can also attack and damage the immune system and interfere with its ability to defend the body.

An allergy is a disease in which the immune system makes an inflammatory response to a harmless antigen. Any antigen that causes an allergy is called an allergen. Allergens may be inhaled or ingested, or they may come into contact with the skin. Two common causes of allergies are shown in Figure below. Inhaling ragweed pollen may cause coughing and sneezing. Skin contact with oils in poison ivy may cause an itchy rash. Other common causes of allergies include dust mites, mold, animal dander, insect stings, latex, and certain food and medications. Symptoms of a common allergy such as pollen can include sneezing, a runny nose, nasal congestion and itchy, watery EYES.

MECHANISM OF ANTIBODY IgE.

The exaggerated response of the immune system to certain antigens present in the environment is called allergy. The substances to which such an immune response is produced are called allergens. The antibodies produced to these are of IgE type. Common examples of allergens are mites in dust, pollens, animal dander, etc. Symptoms of allergic reactions include sneezing, watery eyes, running nose and difficulty in breathing. Allergy is due to the release of chemicals like histamine and serotonin from the mast cells. For determining the cause of allergy, the patient is exposed to or injected with very small doses of possible allergens, and the reactions studied. The use of drugs like anti-histamine, adrenalin and steroids quickly reduce the symptoms of allergy. Somehow, modern-day life style has resulted in lowering of immunity and more sensitivity to allergens – more and more children in metro cities of India suffer from allergies and asthma due to sensitivity to the environment. This could be because of the protected environment provided early in life.

The symptoms of allergies can range from mild to severe. Mild allergy symptoms are often treated with antihistamines. These are drugs that reduce or eliminate the effects of the histamines that cause allergy symptoms. Recall that histamines trigger the inflammatory response. The most severe allergic reaction is called anaphylaxis. This is a life-threatening response caused by a massive release of histamines. It requires emergency medical treatment.

Summary

• Allergies occur when the immune system makes an inflammatory response to a harmless antigen.
• An antigen that causes an allergy is called an allergen.

HOMEWORK TASK :-

1. What is an allergen? Give two examples.
2. Define anaphylaxis. What causes the symptoms of anaphylaxis?
3. Sometimes people with an allergy get allergy shots. They are injected with tiny amounts of the allergen that triggers the allergic reaction. The shots are repeated at regular intervals, and the amount of allergen that is injected each time gradually increases. How do you think this might help an allergy? Do you think this approach just treats allergy symptoms or might it cure the allergy?

That's all for today .

I will see your tomorrow according to DAY 3 time table.

ASK YOUR DOUBTS ???