Allergy Symptoms: Learn more about the many causes of the allergy with the Symptom Checker

Allergy Symptoms

Symptom Checker: Symptoms & Signs Index

Medical Reviewer: Melissa Conrad Stöppler, MD

Allergies are exaggerated immune responses to environmental triggers known referred to as allergens. Allergies are very common, and about 50 million people in North American suffer from allergies. One of the most common forms of allergy is allergic rhinitis ("hay fever"), which produces symptoms like nasal congestion, watery eyes, itching of the eyes and nose, sneezing, runny nose, scratchy throat, and throat clearing from postnasal drip. Other types of allergic reactions can involve the skin (hives and itching). Anaphylactic shock is a severe form of allergic reaction that can be life-threatening. In anaphylactic shock, there is swelling of the throat and difficulty breathing. Asthma is also related to allergies in many cases.

The symptoms of allergies can sometimes resemble those of other conditions. The common cold and the flu can cause respiratory symptoms similar to allergies. Typically, allergy symptoms are associated with a specific time of year or exposure to an allergen. This list focuses on allergies and other types of conditions that may cause some or many of the same symptoms as a cold.

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REFERENCE: WebMD.com. Allergy Types.

Main Article on Allergy

Allergy An allergy refers to a misguided reaction by our immune system in response to bodily contact with certain foreign substances. ...learn more »
Terms related to Allergy:
- Allergic Reaction
- Allergic Symptoms
- Hay Fever Symptoms

Causes of Allergy

Acute Bronchitis Bronchitis is a disease of the respiratory system in which the bronchial passages become inflamed. There are two types of...learn more »
In This Article
Acute Bronchitis Article
- Acute bronchitis facts
- What is acute bronchitis?
- What causes acute bronchitis?
- What are the risk factors for acute bronchitis?
- What are the symptoms of acute bronchitis?
- When does a cold become acute bronchitis?
- How is acute bronchitis diagnosed?
- When should I call my doctor about my cough?
- What are the treatments for acute bronchitis?
- What are acute bronchitis home remedies?
- What are the complications of acute bronchitis?
Adenovirus 14 Adenovirus infection, particularly Ad14, or the "killer cold virus" has been on the increase in the past two years. Symptoms...learn more »
In This Article
Adenovirus 14 Article
- Adenovirus 14 (Ad14) facts
- What is the killer cold virus?
- What are symptoms and signs of an Adenovirus 14 infection?
- What causes an infection with Adenovirus 14 (Ad14)?
- How is an Adenovirus 14 infection diagnosed?
- What is the treatment for an Adenovirus 14 infection?
- What are complications of an Adenovirus 14 infection?
- What is the prognosis for an Adenovirus 14 infection?
- Can an Adenovirus 14 infection be prevented?
- Where can people get more information about the killer cold virus (Adenovirus 14)?
Common Cold The common cold (viral upper respiratory tract infection) is a contagious illness that may be caused by various viruses. Symptoms...learn more »
In This Article
Common Cold Article
- What is the common cold, and what causes it?
- How is the common cold transmitted?
- What are the symptoms and signs of the common cold in adults, children, and infants?
- Does it have anything to do with exposure to cold weather?
- What is the difference between the common cold and influenza (the flu)?
- How is the common cold diagnosed?
- What is the treatment for the common cold? Are there any home remedies for the common cold?
- Are antibiotics a suitable treatment for the common cold?
- When should a physician or other health-care practitioner be consulted?
- How do you prevent the common cold?
- Common Cold At A Glance
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In This Article
Flu (Influenza) Article
- Flu (influenza, conventional, and H1N1) facts
- What is influenza?
- What are the causes of the flu?
- What are flu symptoms in adults and in children?
- How is the flu diagnosed?
- What is the key to flu prevention?
- Are there any flu shot or nasal spray vaccine side effects in adults or in children?
- Why should the influenza vaccine be taken every year?
- What are some treatments an individual can do at home for the flu?
- When should a person go to the emergency department for the flu?
- Who should receive the flu vaccine, and who has the highest risk factors? When should someone get the flu shot?
- What is the prognosis (outlook) and complications for patients who get the flu?
- What is the bird (avian) flu?
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- Is it safe to get a flu shot that contains thimerosal?
- Where can I find additional information about the flu?
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In This Article
Food Allergy Article
- Food allergy facts
- Introduction to food allergies
- How do allergic reactions to food occur?
- What are the symptoms and signs of food allergy?
- Do infants and children have problems with food allergy?
- What are the most common food allergies?
- What is cross-reactivity?
- What is oral allergy syndrome?
- What is exercise-induced food allergy?
- What conditions have mistakenly been attributed to food allergy?
- What conditions mimic food allergy?
- How is food allergy diagnosed?
- What is the treatment for a food allergy?
- Are allergy shots effective for food allergy?
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In This Article
Infectious Mononucleosis Article
- Infectious mononucleosis (mono) facts
- What is infectious mononucleosis?
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- What are the complications of mono?
- How can mono be prevented?
- Conclusion
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In This Article
Measles Article
- Measles facts
- What is measles?
- What is rubeola?
- What is rubella?
- What are other names for measles?
- What is the history of measles?
- What causes measles?
- How is measles spread?
- How does one become immune to measles?
- Who is at risk for getting measles?
- Is measles deadly?
- What is the danger of getting measles while pregnant?
- If I am exposed, how long does it take to develop symptoms and signs?
- What are measles symptoms and signs?
- What are the complications seen with measles?
- What is atypical measles?
- What is modified measles?
- How is the diagnosis of measles made?
- If it is not measles, what else could it be?
- What should I do if I have been exposed to measles?
- Is there any treatment for measles after symptoms and signs develop?
- If measles only rarely occurs in the United States, why should I get vaccinated?
- Do I need to be revaccinated against measles if I am traveling to Europe?
- What is the prognosis for measles?
- How can I prevent contracting measles?
- Is there any truth to the fear of getting autism from vaccines?
- Who should not receive measles vaccinations?
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- What adverse reactions can occur to the measles vaccination?
- Who should be revaccinated against measles?
- Where can I find more information about measles?
Pink Eye Pink eye, also called conjunctivitis, is redness or irritation of the conjunctivae, the membranes on the inner part of the...learn more »
In This Article
Pink Eye Article
- Pink eye facts
- What is "pink eye"?
- What infections cause pink eye, what are infectious pink eye symptoms, and how are they treated?
- What noninfectious conditions cause pink eye, what are noninfectious pink eye symptoms, and how are they treated?
- What are home treatments and care for pink eye?
- How can I prevent the spread of pink eye?
Poison Ivy Poison ivy, oak, and sumac are plants that cause an itchy skin rash and skin inflamation when contacted directly. This poison can...learn more »
In This Article
Poison Ivy Article
- Poison ivy, oak, and sumac facts
- What causes the rash? How do I identify poison ivy, oak, and sumac?
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In This Article
Respiratory Syncytial Virus Article
- Respiratory syncytial virus (RSV) infection facts
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In This Article
Sinus Infection Article
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- Related sinus infection article:
  Sinus infection - on eMedicineHealth
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In This Article
Smoking (How to Quit Smoking) Article
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In This Article
Smoking During Pregnancy Article
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In This Article
Strep Throat Article
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In This Article
Whooping Cough (Pertussis) Article
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