Overview
Allergies occur when your immune system acts to foreign substances or the allergens that are pollen, beet venom, or a food that causes a reaction in most people. Your immune system produces substances which are known as antibodies. The immune system is a complex system that normally prevents the body from foreign invaders such as bacteria and viruses while also surveying for abnormal changes in an individual’s own cells.
Allergens are substances that are foreign to the body and that are the source of an allergic reaction. IgE is the allergic antibody whereas the other antibodies are IgG, IgM, and IgA, which fight against the infection. Although many individuals outgrow allergies over a period of time, allergies can also develop at any age.
What Is An Allergy?
An allergy is an exaggerated reaction by the immune system relevant to exposure to certain foreign substances. The response is exaggerated because these irritant substances are normally seen as harmless by the immune system that generates the response.
What Causes Allergy?
An allergy begins when your immune system mistakes a safe substance for an invader. The immune system generates the antibodies that remain on the alert for that particular allergen. When you are exposed to the allergen, the antibodies can release a number of immune system chemicals such as histamine that causes the symptoms of allergy.
Common allergy triggers are:
- Airborne allergens like pollen, dust mites, and mold.
- Certain foods such as peanuts, tree nuts, wheat, soy, fish, egg, and milk.
- Insect stings such as bees.
- Medications such as penicillin or other antibiotics.
- Latex or other substances you touch causes an allergy reaction.
Common Type Of Allergy With Its Sign And Symptoms
The part of the body that is prone to allergic symptoms includes the eyes, nose, lungs, skin although the various allergic diseases may appear different as they all result from an exaggerated immune response to the substances in sensitive individuals.
The following are brief about common allergic disorders. They are:
1)Allergic rhinitis (hay fever)
Allergic rhinitis is the most common allergic disease and this refers to the nasal symptoms that are due to aeroallergens. Year-round, allergic rhinitis is usually caused by indoor allergens such as dust mites, molds. Seasonal allergic rhinitis is typically caused by trees, grass. Many individuals have both seasonal and perennial allergies. Symptoms result from the inflammation of the tissue that lines the inside of the nose after exposure to irritants. The ears, sinuses, and throat can also be involved which is the most common symptoms that include:
- Runny nose
- Stuffy nose
- Sneezing
- Postnatal drip
- Itchy nose, ears as well as throat
In 1819, an English physician whose name is John Bostock first described hay fever by detailing his own seasonal nasal symptoms which are called the “summer catarrh”. The condition was called hay fever as it was thought to be caused by the “new hay”.
2) Asthma
Asthma is a respiratory condition that results from inflammation and hyperactivity of the airways, results in recurrent, reversible constriction of the airways. Asthma can often coexist with allergic rhinitis. Other common triggers include respiratory viral infections. Common symptoms include:
- Shortness of breath
- wheezing
- coughing
- chest tightness
3) Allergic Eyes (Conjunctivitis)
Allergic eyes are the inflammation of the tissue layers that cover the surface of the eyeball and the undersurface of the eyelid. The inflammation occurs as a result of an allergic reaction and may produce the following symptoms which present in both of the eyes that includes:
- Redness under the lids
- Watery, itchy eyes
- Swelling of the membranes
4) Eczema (atopic dermatitis)
Eczema is a condition that is commonly found in infants which tends to occur in individuals at risk for other allergic conditions but is not usually caused by direct allergens. The rash result from a complicated inflammatory process in which the common symptoms include:
- Dry skin associated with significant itching
- Involvement of the face, the front of elbows, and behind knees where the rash can occur.
5) Hives ( urticaria)
Hives are the skin reaction that appears as red, raised, itchy welts which can occur at any part of the body. Short-lived hives are often due to an allergic reaction to a food or medication as they also commonly result from a viral infection in children. They can also result from contacts such as licking from the dogs, cats, or any of the pets. Hives that recur over a longer period are rarely due to a reaction of the allergens. It is characterized by:
- Intense itching
- No residual marks
- Swelling particularly of the lips, face, and hands.