What are allergies?

Allergies occur when your body’s immune system encounters a substance as foreign or harmful and overreacts to it. These substances are called allergens. Your immune system produces antibodies. When you have allergies, the immune system produces these antibodies to identify an allergen as harmful, even though it may not be. When you encounter these allergens, the reaction can inflame several areas of your body. These reactions can range from mild to life-threatening (anaphylaxis).

What are the symptoms of allergies?

Allergy symptoms depend on the substance or allergen involved. It can affect your sinuses, airways, skin, or digestive systems. It also is dependent on the amount of allergen encountered, and how the immune system reacts to it.

Common symptoms of a typical allergy include:

  • Sneezing
  • Runny, stuffy nose
  • Watery, swollen, or red eyes
  • Itching of the eyes, nose, or roof of the mouth

What are the causes of allergies?

An allergy is caused by your immune system mistakenly reacting to a normal, harmless substance. These substances are allergens and are viewed as dangerous by the immune system. Antibodies respond to allergens, and the result is an allergic reaction. Allergens can be ingested, inhaled, or enter through the skin.

Common allergens include:

  • Insects
  • Mold
  • Drug
  • Food
  • Pet
  • Latex
  • Pollen

Can any complications arise if left untreated?

Anaphylaxis is a life-threatening reaction to allergy triggers. It causes all areas of the body to swell, including the throat. It is also characterized by a drop in blood pressure. Other symptoms include difficulty breathing, fever, pain, and nausea. Anaphylaxis is considered emergent and medical treatment should immediately be sought out.

What medications treat allergies?

Allergy treatment can include three approaches: avoiding triggers/allergens, use of medication, or immunotherapy. If you’ve had a bad allergic reaction in the past, medical alert bracelets can help to alert others if you get sick.


Allergies - Asthma and Allergy Foundation of America

Allergies - Mayo Clinic

Allergies and the Immune System - Johns Hopkins

Common medications may include

Allergenic Desensitization Agents
Asthma Therapy - Glucocorticoids
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Asthma Therapy - Inhaled Corticosteroids (Glucocorticoids)
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Cough & Cold or Allergy Combinations
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