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Anaphylaxis: Introduction

Anaphylaxis is the most severe form of an allergic reaction. Anaphylaxis, also called an anaphylactic reaction or allergic shock, can be fatal. Anaphylaxis develops rapidly, often within minutes, and is a life-threatening condition that requires immediate emergency care.

Anaphylaxis is an uncommon type of allergic reaction. There are a variety of types of allergies that may in some cases develop into anaphylaxis. Almost any allergen can produce anaphylaxis in a person who is extremely sensitive to that particular substance. Common causes of anaphylaxis in include food allergies, such as an allergy to shellfish, peanuts or other nuts, and allergies to certain insect bites, such as a bee or wasp sting. Another common cause of anaphylaxis is a reaction to a medication, such as to aspirin or penicillin. Allergies to certain substances, such as latex, can in some cases cause anaphylaxis.

Anaphylaxis is caused by a severe over-reaction of the immune system to a particular substance or allergen. The immune system is made up of special cells that circulate throughout the body to defend the body against foreign substances, such as viruses and bacteria. For people with allergies that lead to anaphylaxis, the immune system is overzealous and reacts when they exposed to normally harmless substances, such as peanuts or latex. This results in the release of certain chemicals including histamine. These chemicals cause rapid and severe swelling, inflammation, and itching of tissues. This can result a narrowing or complete blockage of the windpipe and a sudden drop in blood pressure (hypotension). Symptoms include shortness of breath, hives, and rapid pulse. For more information on symptoms and complications, refer to symptoms of anaphylaxis.

Anaphylaxis is often diagnosed quickly in an emergency setting by the symptoms and by taking a quick allergy history and history of recent exposure to possible allergens that commonly cause anaphylaxis.

After a person with anaphylaxis has received emergency treatment and is stabilized, an allergist or specialist in immunology will make a diagnosis of the underlying allergy if they are unknown. This includes performing a complete evaluation that includes a medical history and allergy history, including exposure to common allergens, symptoms, and a physical examination. In some cases, it may not be possible to identify what substance caused anaphylaxis.

Diagnostic testing may include skin patch testing. In a patch test, small amounts of common allergens are applied methodically to the skin to determine what substances are triggering an allergic response that can lead to anaphylaxis. For suspected food allergies, a patient may also be asked to keep a log to record the types of foods that trigger an allergic reaction or to eliminate common food allergens, such as nuts.

It is possible that a diagnosis of anaphylaxis can be missed or delayed because some symptoms can be similar to symptoms of other conditions. For more information on diseases and conditions that can mimic anaphylaxis, refer to misdiagnosis of anaphylaxis.

Patient compliance with a good treatment plan can reduce the risks of developing anaphylaxis or repeat episodes of anaphylaxis. Treatment may include a combination of lifestyle changes, medications, and other measures. For more information on treatment, refer to treatment of anaphylaxis. ...more »

Anaphylaxis: A rare, potentially life-threatening allergic reaction. More detailed information about the symptoms, causes, and treatments of Anaphylaxis is available below.

Anaphylaxis: Symptoms

People who have anaphylaxis can experience a variety of symptoms that can affect the respiratory system, skin, gastrointestinal system, and the cardiovascular system.

Respiratory symptoms include shortness of breath, wheezing, difficulty breathing, and difficulty swallowing or speaking due to swelling of the throat, tongue or windpipe. Swelling ...more symptoms »

Anaphylaxis: Treatments

The most effective treatment plan for anaphylaxis uses a multifaceted approach. Treatment plans are also individualized to best address the specific cause and severity of anaphylaxis, and the patient's age and medical history. In general, the allergies that can lead to anaphylaxis are treatable, although they are generally not curable.

Treatment ...more treatments »

Anaphylaxis: Misdiagnosis

A diagnosis of anaphylaxis may be overlooked or delayed because some symptoms may be can mimic symptoms of other conditions, such as a panic attack or syncope.

The allergies that can cause anaphylaxis can be difficult to diagnose and may be both over-diagnosed and under-diagnosed at different times. A full evaluation by a primary care physician or nurse practitioner in ...more misdiagnosis »

Symptoms of Anaphylaxis

Treatments for Anaphylaxis

Home Diagnostic Testing

Home medical testing related to Anaphylaxis:

Wrongly Diagnosed with Anaphylaxis?

Anaphylaxis: Related Patient Stories

Anaphylaxis: Deaths

Read more about Deaths and Anaphylaxis.

Anaphylaxis: Complications

Review possible medical complications related to Anaphylaxis:

Causes of Anaphylaxis

More information about causes of Anaphylaxis:

Disease Topics Related To Anaphylaxis

Research the causes of these diseases that are similar to, or related to, Anaphylaxis:

Anaphylaxis: Undiagnosed Conditions

Commonly undiagnosed diseases in related medical categories:

Misdiagnosis and Anaphylaxis

Chronic lung diseases hard to diagnose: Some of the chronic lung diseases are difficult to diagnose. Even the well-knowns conditions such as asthma or lung cancer often more »

Anaphylaxis: Research Doctors & Specialists

Research related physicians and medical specialists:

Other doctor, physician and specialist research services:

Hospitals & Clinics: Anaphylaxis

Research quality ratings and patient safety measures for medical facilities in specialties related to Anaphylaxis:

Choosing the Best Hospital: More general information, not necessarily in relation to Anaphylaxis, on hospital performance and surgical care quality:

Anaphylaxis: Rare Types

Rare types of diseases and disorders in related medical categories:

Latest Treatments for Anaphylaxis

Anaphylaxis: Animations

Prognosis for Anaphylaxis

Research about Anaphylaxis

Visit our research pages for current research about Anaphylaxis treatments.

Clinical Trials for Anaphylaxis

The US based website lists information on both federally and privately supported clinical trials using human volunteers.

Some of the clinical trials listed on for Anaphylaxis include:

Statistics for Anaphylaxis

Anaphylaxis: Broader Related Topics

Anaphylaxis Message Boards

Related forums and medical stories:

User Interactive Forums

Read about other experiences, ask a question about Anaphylaxis, or answer someone else's question, on our message boards:

Definitions of Anaphylaxis:

OBSOLETE. Extreme immunological sensitivity of the body or tissues to the reintroduction of an antigen. It is a form of anamnestic reaction and is accompanied by pathological changes in tissues or organs due to the release of pharmacologically active substances. [ISBN:0198506732] - (Source - Diseases Database)

Hypersensitivity reaction to the ingestion or injection of a substance (a protein or drug) resulting from prior contact with a substance - (Source - WordNet 2.1)

Anaphylaxis is listed as a "rare disease" by the Office of Rare Diseases (ORD) of the National Institutes of Health (NIH). This means that Anaphylaxis, or a subtype of Anaphylaxis, affects less than 200,000 people in the US population.
Source - National Institutes of Health (NIH)


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