Allergies

An allergy is an immune system response to a foreign

substance that’s not typically harmful to your body. These

foreign substances are called allergens. They can include

certain foods, pollen, or pet dander.

Your immune system’s job is to keep you healthy by fighting

harmful pathogens. It does this by attacking anything it thinks

could put your body in danger. Depending on the allergen, this

response may involve inflammation, sneezing, or a host of

other symptoms.

Your immune system normally adjusts to your environment. For

example, when your body encounters something like pet

dander, it should realize it’s harmless. In people with dander

allergies, the immune system perceives it as an outside invader

threatening the body and attacks it.

Allergies are common. Several treatments can help you avoid symptoms.

Allergens

An allergen is a usually harmless substance capable of triggering a response that starts in the immune system and results in an allergic reaction.

For instance, if you have an allergy to pollen, your immune system identifies pollen as an invader or allergen. The immune system responds by releasing chemicals that typically cause symptoms in the nose, throat, eyes, ears, skin or roof of the mouth.

In addition to pollen, other common allergens include dust mites, animal dander, mould, medications, insect venoms and various

foods.

Allergic reactions

Some people sneeze like crazy. Others get itchy hives or watery eyes. But whatever the reaction, it boils down to one thing: allergies.

Learning why these reactions happen can help you keep things under control and feel better.

Why Allergic Reactions Happen

Your immune system has an important job: to defend your body from invaders such as bacteria and viruses that mean you harm.

But when it makes war on substances it shouldn’t, that’s an allergy.

Peanuts, eggs, or pollen, for example, can trigger reactions. They are called allergens.

During a reaction, your immune system releases antibodies. These are proteins that deliver a message to cells: Stop that substance! The cells then send out histamine, which causes blood vessels to expand, and other chemicals, and these trigger the allergy symptoms.

These antibodies are singled-minded. Each one targets only one type of allergen. That explains why someone might be allergic to peanuts but not to eggs.

You can come into contact with allergens in many ways: through the skin, eyes, nose, mouth, or stomach. This can cause your sinuses to clog up, inflame your skin, make it harder to breathe, or cause stomach problems.

What Things Most Often Cause an Attack?

Why do some people have such bad allergies and others don’t? Experts don’t have all the answers, but they say family history is important.

Some common allergens include:

Animal dander Bee stings Certain medications such as penicillin Dust mites Foods -- particularly peanuts, tree nuts, fish,

shellfish, eggs, milk, wheat, and soy

Insect bites Latex or other materials you touch Mould Plants and pollens

The Symptoms, From Itchy Eyes to Sneezing

Your allergy attacks might range from mild and annoying to more severe and even life-threatening. It all depends on the way your body reacts and how much of the allergen got into your system.

If the allergy is severe, the person may have a serious reaction called anaphylaxis. Some cases could be life-threatening and need urgent attention.

Here are some common types of allergies:

Hay fever: Also known as allergic rhinitis, it can cause:

Sneezing Runny or stuffy nose Itchy eyes, nose or roof of mouth Red, swollen, watery eyes -- a condition known

as allergic conjunctivitis

Food allergies: You may feel tingling in your mouth. Your tongue, lips, throat, or face might swell up. Or you could get hives. In the worst cases, you might have anaphylaxis and will need medical help right away.

Eczema: Also known as atopic dermatitis, it is a skin

condition. Most types of eczema are not allergies. But the disease can flare up when you're around things that cause an allergic reaction. Your body's immune system overreacts to substances, called allergens that are usually not harmful. You might get hives, itching,

swelling, sneezing, and a runny nose. You might have it if you have itching, redness, and peeling or flaking.

Medications: If you’re allergic to a certain drug, you may get a rash, facial swelling, or hives. You could find yourself wheezing. In severe cases, you may develop anaphylaxis.

Stings: If you’re allergic to bees or other insects you may get:

A large area of swelling, known as edema, at the site of the sting

Itching or hives all over your body Shortness of breath, wheezing, chest tightness, or

a cough

As with some other allergies, such as food and medication, a severe reaction to a sting can lead to anaphylaxis.

Anaphylaxis: What Is It and How to Get Help

Most people with allergies get only mild to moderate symptoms, but bad cases can lead to anaphylaxis.

It’s a serious situation and can put your body into shock. Food, medications, insect bites, or latex are the most

likely causes.

A second anaphylactic episode can happen up to 12 hours after the first one.

The symptoms of anaphylaxis can come on suddenly.

They can quickly go from a mild rash or runny nose to serious problems such as a hard time breathing, tightness in the throat, hives or swelling, nausea or vomiting, and fainting or dizziness. Some people can get a rapid pulse or their heart will stop beating.

Treatment:

You can find treatment options for mild to moderate allergic reactions. Antihistamines and decongestants can help treat certain symptoms, as can nasal sprays.

If you have an allergic-type asthma, your doctor might also prescribe an inhaler to ease attacks. Or she may inject a special antibody to manage symptoms.

If you don’t get enough relief by avoiding your allergens and using medications, your doctor may want to give you allergy shots. This type of treatment is called

immunotherapy, and it can be effective for hay fever and allergic asthma.

Another type of immunotherapy involves tablets that dissolve under your tongue.

For your sinuses, an over-the-counter medication might ease your symptoms.

Complications of allergies

While you may think of allergies as those pesky sniffles and sneezes that

come around every new season, some of these allergic reactions can

actually be life-threatening.

Anaphylaxis, for example, is a serious reaction to the exposure of

allergens. Most people associate anaphylaxis with food, but any allergen

can cause the signs:

suddenly narrowed airways

increased heart rate

possible swelling of the tongue and mouth

Allergy symptoms can create many complications. Your doctor can help

determine the cause of your symptoms as well as the difference between a

sensitivity and a full-blown allergy. Your doctor can also teach you how to

manage your allergy symptoms so that you can avoid the worst

complications.

Asthma and allergies

Asthma is a common respiratory condition. It makes breathing more difficult

and can narrow the air passageways in your lungs.

Asthma is closely related to allergies. Indeed, allergies can make existing

asthma worse. It can also trigger asthma in a person who’s never had the

condition.

When these conditions occur together, it’s a condition called allergy-

induced asthma, or allergic asthma. Allergic asthma affects about 60

percent of people who have asthma in the United States, estimates the

Allergy and Asthma Foundation of America.

Types of allergies

1. Perennial Allergens

Perennial (or year-round) allergies may be less intense than pollen-based or seasonal allergies. These are most often seen indoors and

include dust mites, cockroaches, moulds and pets. Pets and moulds

can cause a quicker and more obvious response with itching, sneezing, and nasal congestion. But dust mites and cockroaches cause

more of a general feeling of nasal fullness, congestion and eye

irritation. Asthma can also be triggered by the dust mite and cockroach allergen, which is not always as obvious as a cat or dog allergy.

E.g. for perennial allergies: food allergies

Food allergies can trigger swelling, hives, nausea, fatigue, and more. It

may take a while for a person to realize that they have a food allergy. If you

have a serious reaction after a meal and you’re not sure why, see a

medical professional immediately.

2. Seasonal allergies

Hay fever (caused due to pollen grains) symptoms can mimic those of a

cold. They include congestion, runny nose, and swollen eyes. Most of the

time, you can manage these symptoms at home using over-the-counter

treatments.

Allergies on skin

Skin allergies may be a sign or symptom of an allergy. They may also be

the direct result of exposure to an allergen.

For example, eating a food you’re allergic to can cause several symptoms.

You may experience tingling in your mouth and throat. You may also

develop a rash.

Contact dermatitis, however, is the result of your skin coming into direct

contact with an allergen. This could happen if you touch something you’re

allergic to, such as a cleaning product or plant.

Types of skin allergies include:

Rashes. Areas of skin are irritated, red, or swollen, and can be

painful or itchy.

Eczema. Patches of skin become inflamed and can itch and bleed.

Contact dermatitis. Red, itchy patches of skin develop almost

immediately after contact with an allergen.

Sore throat. Pharynx or throat is irritated or inflamed.

Hives. Red, itchy, and raised welts of various sizes and shapes

develop on the surface of the skin.

Swollen eyes. Eyes may be watery or itchy and look “puffy.”

Itching. There’s irritation or inflammation in the skin.

Burning. Skin inflammation leads to discomfort and stinging

sensations on the skin.

Allergy treatments

The best way to avoid allergies is to stay away from whatever triggers the

reaction. If that’s not possible, there are treatment options available.

Medication

Allergy treatment often includes medications like antihistamines to control

symptoms. The medication can be over the counter or prescription. What

your doctor recommends depends on the severity of your allergies.

Allergy medications include:

antihistamines like diphenhydramine (Benadryl)

corticosteroids

cetirizine (Zyrtec)

Immunotherapy

Many people opt for immunotherapy. This involves several injections over

the course of a few years to help the body get used to your allergy.

Successful immunotherapy can prevent allergy symptoms from returning.

Emergency epinephrine

If the person has a severe, life-threatening allergy, they need to carry an

emergency epinephrine shot. The shot counters allergic reactions until

medical help arrives.

How allergies are diagnosed

The doctor can diagnose allergies in several ways:

First, the doctor will ask about your symptoms and perform a physical

exam. They’ll ask about anything unusual you may have eaten recently and

any substances you may have come in contact with. For example, if you

have a rash on your hands, your doctor may ask if you put on latex gloves

recently.

Lastly, a blood test and skin test can confirm or diagnose allergens your

doctor suspects you have.

Allergy blood test

Your doctor may order a blood test. Your blood will be tested for the

presence of allergy-causing antibodies called immunoglobulin E (IgE).

These are cells that react to allergens. Your doctor will use a blood test to

confirm a diagnosis if they’re worried about the potential for a severe

allergic reaction.

Skin test

Your doctor may also refer you to an allergist for testing and treatment. A

skin test is a common type of allergy test carried out by an allergist.

During this test, your skin is pricked or scratched with small needles

containing potential allergens. Your skin’s reaction is documented. If you’re

allergic to a particular substance, your skin will become red and inflamed.

Preventing symptoms

There’s no way to prevent allergies. But there are ways to prevent the

symptoms from occurring. The best way to prevent allergy symptoms is to

avoid the allergens that trigger them.

Avoidance is the most effective way to prevent food allergy symptoms. An

elimination diet can help you determine the cause of your allergies so you

know how to avoid them. To help you avoid food allergens, thoroughly read

food labels and ask questions while dining out.

Preventing seasonal, contact, and other allergies comes down to knowing

where the allergens are located and how to avoid them. If you’re allergic to

dust, for example, you can help reduce symptoms by installing proper air

filters in your home, getting your air ducts professionally cleaned, and

dusting your home regularly.

Proper allergy testing can help you pinpoint your exact triggers, which

makes them easier to avoid. These other tips can also help you avoid

dangerous allergic reactions.

https://www.youtube.com/watch?v=hmb066Vzdek

WORK SHEET

FILL IN THE BLANKS

1. __________ is a serious life threatening reaction.

2. The basic medications for allergies are ________.

3. Antibodies cause certain cells in the body to release __________ which

causes the symptoms of allergic reactions.

4. The substances that can trigger an immune response are called

_________.

5. __________ allergies rise with the change in the season.

CHOOSE THE BEST.

1. Allergy is an example of

a) Communicable disease

b) Non communicable disease

c) None of the above

2. Food allergy is a type of __________.

a) Perennial allergy

b) Seasonal allergy

c) Both

3. Chemicals that immune cells release are called

a) Histamine

b) Anti histamine

c) Fluids

4. Pollens, animal fur and house dust are examples of

a) Air borne allergens

b) Drug allergens

c) Food allergens

5. Asthma affects the __________.

a) Skin

b) Lungs

c) Heart

6. Allergic reaction mark by red, raised areas of the skin.

a) Hives

b) Nausea

c) Cramps

CORRECT THE FALSE STATEMENTS.

1. Allergy is the reaction of hyposensitivity of the body tissues to certain

substances.

2. Perennial allergy is caused during certain seasons.

3. Histamines are the basic medication provided for allergies.

4. Substances that trigger an allergy are called allergic reactions.

5. Asthma is a serious, life threatening allergic reaction.

WORK SHEET ANSWERS.

Fill ups

1. Anaphylaxis

2. Anti-histamine

3. Histamine

4. Antigens

5. Seasonal

Choose the best

1. Non communicable disease.

2. Perennial allergy

3. Histamine

4. Air borne allergens

5. Lungs

6. Hives

CORRECT THE FALSE STATEMENT

1. Allergy is the reaction of hypersensitivity of the body tissues to certain

substances.

2. Seasonal allergy is caused during certain seasons.

3. Anti-histamines are the basic medication provided for allergies.

4. Substances that trigger an allergy are called allergens.

5. Anaphylaxis is a serious, life threatening allergic reaction.

Text book short Question and Answers.

1. Name the five most common allergens.

Ans: Pollen grain, animal fur, strong sunlight, house dust, certain food

items.

2. What are the two major types of allergies?

Ans: Perennial allergy

This allergy may occur any time of the year. Unrelated to the season and

may last all year round. Example: food allergy.

Seasonal allergy

The allergy that occur during certain seasons of the year are called as

seasonal allergy. Example: hay fever.

3. What is the inexpensive way to avoid allergen?

Ans: The most certain treatment for allergies is to avoid the substances that

trigger them and strictly follow the preventive measures to avoid allergens.

4. (Omit)

5. What are the precautions taken against dust and pollen allergies?

Ans:

To avoid dust allergies, we must keep the house dust free and clean.

And wear a mask if we go outside.

To avoid pollen allergies immunotherapy (allergy shots) can be taken

or decrease exposure to the pollen grains by wearing a mask.

6. What is Anaphylaxis?

Ans: Anaphylaxis is a severe life threatening reaction to certain allergens.

The body tissues may swell including tissues in the throat and there is a

sudden drop in the blood pressure.

7. (omit)