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All about asthma types of asthma bronchial asthma exercise induced asthma adult-onset asthma status asthmaticus causes of asthma asthma triggers asthma and allergy asthma attack asthma in children asthma and pregnancy asthma in adults and older people complications of asthma symptoms of asthma warning signs of asthma asthma diagnosis asthma treatments asthma relief (rescue) medications asthma long-term control medications asthma inhalers asthma nebulizers control acute asthma attacks management of chronic asthma symptoms asthma relievers asthma preventers childhood asthma cures treatment for asthma in the elderly asthma prevention

Asthma and allergy

Asthma attacks (worsening of asthma symptoms) can be triggered by allergies, which can temporarily increase the inflammation of the airways in a susceptible person. Allergy is the leading cause of asthma, and about 90% of children under the age of 10 with asthma have allergies. About 70% of people under 30 with asthma and 50% of those over 30 with asthma also have allergies. In relation to the home environment, triggers can be grouped into two primary categories:

allergens and irritants. Allergens are typically defined as something that causes an allergic reaction in some people, but not others. Indoor allergens include dust mites, cockroach debris, pet dander, and mold. Irritants are substances that irritate the respiratory tract and include tobacco smoke and paint fumes.

Allergies are the immune system's reaction when exposed to what is otherwise a harmless substance, such as plant pollen, mold or animal hair, skin or saliva. For people with allergies, the immune system treats these substances, called "allergens," as if they are harmful, causing a disruption to normal body functions. Allergies cause the body to have a physical response to substances known as allergens. When this response occurs, the immune system is overreacting to a substance that does not cause any reaction at all in most people.

Essentially, an allergic reaction occurs when the body sends a signal to the immune system that a harmful substance is present. When one of these substances enters the body -- pollen, for example -- the person with an allergy develops an excess of an antibody called immunoglobulin E. These antibodies react with allergens to release histamines. It’s the histamines that produce allergic symptoms (stuffy nose, sneezing, etc.). If a person has allergies, his immune system reacts to these allergens as if the allergens were invading the body. To fight the allergen, his immune system produces an antibody called immunoglobulin E (IgE). If the IgE combines with the allergen, this sets a process in motion that results in the release of certain substances in the body. One of the substances released is histamine, which causes allergic symptoms that can affect the eyes, nose, throat, skin, gastrointestinal tract, or lungs. When the airways in the lungs are affected, symptoms of asthma (such as coughing, wheezing, or difficulty breathing) can occur when the body is exposed to the allergen.

An Allergy is a response to a substance, called allergens, that produce a reaction in the body. When the immune system is exposed to allergens, it produces antibodies which attach themselves to certain cells in the body called "mast cells." These mast cells see the invading particle as a threat and release substances such as Histamine to destroy the intruder particle, but these substances also produce undesirable allergic reactions. When the reaction takes place in the nose and sinuses, it is called Hay Fever or allergic rhinitis. When the reaction to allergens occurs in the skin it is called Hives. An allergic reaction that occurs over the whole body can be life threatening and is called Anaphylaxis. A reaction in the stomach is a Food Allergy and when an allergic reaction due to allergens happens in the lungs, it is called allergic Asthma. Asthma is a chronic illness that causes breathing problems and is considered a lung disease. The rarest type of allergic reaction is called anaphylactic shock. This is a severe reaction that can affect many organs at once. Symptoms include rapid decrease in blood pressure, rash or hives, difficulty breathing, abdominal pain, swollen tongue or throat, diarrhea, fainting and sometimes.

Many different substances cause allergic reactions. Some are toxic, such as exhaust fumes, and others are non-toxic, like pollen and food. The most common allergens include pollen from trees, grasses and weeds, dust mite particles, cockroaches, tobacco smoke, paint fumes, gasoline fumes, pet dander (skin, saliva, hair or fur), mold spores, and foods (most commonly, peanuts, shellfish, milk, eggs and wheat). Parents who have allergies or asthma often pass along the tendency to have these conditions to their kids.

An allergy is an abnormal reaction by the body to substances which it is sensitized to. These substances are called allergens, and an allergic person produces antibodies against these allergens. Each time the allergic person comes in contact with an allergen after that first contact, certain cells in the body release chemical substances called mediators. Mediators, like histamine and leukotrienes, can cause one or more of the following symptoms: redness, swelling, itching and increased mucous production. With an allergy to pollens, there may be itchy eyes and runny nose. With an allergy to cats, there may be itchy eyes and swelling in the lungs.

More information on asthma

What is asthma? - Asthma is a chronic inflammatory respiratory disease characterized by periodic attacks of wheezing, shortness of breath, and a tight feeling in the chest.
What types of asthma are there? - Types of asthma include child-onset asthma, adult-onset asthma, exercise-induced asthma, cough-variant asthma, occupational asthma, nocturnal asthma.
What's bronchial asthma? - Bronchial asthma is a disease of the lungs in which an obstructive ventilation disturbance of the respiratory passages evokes a feeling of shortness of breath.
What is exercise-induced asthma? - Exercise-induced asthma is a form of asthma that some people have during or after physical activity. Exercise-induced asthma is common.
What is adult-onset asthma? - Adult onset asthma generally is the onset of asthma for the first time in someone of middle age or older. Adult-onset asthma develops after age 20.
What is status asthmaticus? - Status asthmaticus is a severe asthma episode that does not respond to standard treatment. Status asthmaticus is caused by severe bronchospasm.
What causes asthma? - Asthma is caused by inhaling an allergen that sets off the chain of biochemical and tissue changes leading to airway inflammation, bronchoconstriction, and wheezing.
What're the asthma triggers? - Many risk factors have been linked to triggering asthma attacks. There are two basic types of asthma triggers, allergic triggers, non-allergic triggers.
Asthma and allergy - Asthma attacks (worsening of asthma symptoms) can be triggered by allergies. Allergy is the leading cause of asthma.
What is an asthma attack? - An asthma attack occurs when the small and medium-sized airways become inflamed and constricted after being exposed to a trigger.
Asthma in children - Asthma is the most common chronic condition of childhood. Asthma symptoms can interfere with many school activities for children.
Asthma and pregnancy - During pregnancy, asthma or asthma episodes will become worse for an estimated one-third of pregnant women, particularly women who have severe asthma.
Asthma in adults and older people - Identifying asthma in the elderly can be difficult because asthma symptoms can be confused with symptoms of heart or lung diseases.
What're the complications of asthma? - Uncontrolled asthma in pregnant women puts them at higher risk for complications that can include early labor, hypertension, gestational diabetes.
What are the symptoms of asthma? - The symptoms of asthma include labored breathing, constriction of the chest, coughing and gasping usually brought on by allergies.
What're the warning signs of asthma? - Most people with asthma have warning signs before symptoms appear. There are many warning signs of an asthma episode.
How is asthma diagnosed? - The diagnosis of asthma is made on the basis of typical symptoms and signs. Positive allergy tests support a diagnosis of asthma.
What're the treatments for asthma? - Treatment of asthma is aimed at avoiding known allergens and respiratory irritants and controlling symptoms and airway inflammation through medication.
What quick relief (rescue) medications cure asthma? - Short-acting beta-agonists are the most commonly used asthma rescue medications. Anticholinergics are another class of asthma drugs.
Long-term asthma control medications - Combinations of steroids and other medications are effective for both treating and preventing asthma attacks in patients with moderate to severe asthma.
What're asthma inhalers? - Most asthma drugs are inhaled using special devices or nebulizers. Two common types include dry powder asthma inhalers and metered-dose asthma inhalers.
What're asthma nebulizers? - Asthma nebulizers can be used with all classes of inhaled medications but are most commonly used with short-acting beta2 agonists and ipratropium bromide.
How to control acute asthma attacks? - Acute asthma is an acute exacerbation of wheezing, unresponsive to usually effective therapy and necessitating care in an emergency room or hospital ward.
How to manage chronic asthma symptoms? - The aims of management are to recognize asthma, to abolish symptoms, to restore normal or best possible long term airway function.
What asthma relievers are available? - Asthma reliever is a drug that provides relief from asthma symptoms and is the most commonly used asthma medication.
What asthma preventers are available? - Asthma preventers are to be used twice a day regardless of whether your child has symptoms of asthma.
What's the treatment for childhood asthma? - The goals of asthma therapy are to prevent child from having chronic and troublesome symptoms, to maintain child's lung function.
What's the treatment for asthma in the elderly? - Diagnosis and treatment of asthma can be more complicated in people age 65 and older than in those who are younger.
What can be done to prevent asthma? - Avoiding known allergens and respiratory irritants can reduce asthma symptoms. People with asthma should minimize risk for respiratory tract infections.
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