What is an Allergic Reaction?

Key Points

  • You can treat allergic reactions with antihistamines, decongestants, and hydrocortisone creams.
  • Allergic reactions can vary from person to person and depend on the type of allergy.
  • Go to the emergency room if you’re experiencing anaphylaxis, even if the symptoms get better.

Your immune system creates antibodies to fight off foreign substances so you don’t get sick. Sometimes your system will identify a substance as harmful even though it isn’t. When this happens, it’s called an allergic reaction. These substances, or allergens, can be anything from food to medication, or environments.

When your body comes in contact with these allergens, it can cause mild symptoms like skin irritation, watery eyes, or sneezing. In some people allergies can cause anaphylaxis. Anaphylaxis is a life-threatening condition that will cause shock, a sudden drop in blood pressure, and trouble with breathing. This can lead to respiratory failure and cardiac arrest. Call 911 immediately if you or someone you know is experiencing anaphylaxis.

What are the Symptoms of an Allergic Reaction?

Your body’s allergic reaction depends on what you’re allergic to. Parts of your body that can react, include your: airways, nose, skin, mouth, digestive system, etc.

Anaphylaxis or Severe Reactions

The most serious allergic reactions can cause anaphylaxis. This reaction occurs minutes to hours after exposure and, if left untreated, can lead to loss of consciousness, respiratory distress, and cardiac arrest. Signs include:

  • Skin reactions such as hives, itching, or pale skin
  • Wheezing or trouble with breathing
  • Light-headedness, dizziness, or fainting
  • Facial swelling
  • Nausea
  • Weak and fast pulse

Get emergency help if you or someone you know is experiencing anaphylaxis, even if symptoms start to improve. Sometimes symptoms can return.

How to Prevent Allergic Reactions

Once you’ve had an allergic reaction, it’s important to identify the source to avoid future contact. For ingredient-specific allergies, check product ingredients before purchase.

If your allergies cause anaphylaxis, make sure your co-workers and friends know about your allergies and where you keep your epinephrine auto injector or Epipen. Teaching your friends how to treat an allergic reaction can help save a life.


Adapted from: Healthline.com