When to Go to the ER for an Allergic Reaction


Wondering when to go to the ER for an allergic reaction? Though allergies are a common chronic condition, allergic reactions can be dangerous or even life-threatening. We cover allergic reaction symptoms and information in-depth below, but here is a quick guide to when to go to the ER for an allergic reaction.

  • Step 1: If you or a loved one experiences any of the severe allergic reaction symptoms noted below, call 911. Do not wait and see if the symptoms go away on their own. 
  • Step 2: If you have an epinephrine autoinjector, use it as soon as possible.
  • Step 3: Even if you can use an EpiPen and the symptoms of a severe allergic reaction recede, you should still head to the nearest emergency room immediately, where doctors can help monitor for additional reactions such as biphasic anaphylaxis.
  • Step 4: After calling 911, refer to our guide to what to do when someone is in anaphylactic shock for information on how to help individuals experiencing a severe allergic reaction.

For information on allergic reactions in children, please see our article: What to Do if a Child has an Allergic Reaction.

What is considered a serious allergic reaction? Recognizing Anaphylaxis symptoms.

Since there are so many different types of allergic reactions, the signs and symptoms of an allergic reaction can range from mild to severe and often vary from one person to the next. Typical allergic reaction symptoms can include irritated eyes, runny nose, sneezing, itching, hives, cough, and swelling. However, more severe reactions with additional symptoms can occur.

Anaphylaxis –– also known as anaphylactic shock –– is considered one of the most dangerous and life-threatening severe forms of allergic reactions. During anaphylaxis, when the person is exposed to the allergen, the immune system releases chemicals to fight off the allergen that can cause the body to go into shock and become hypersensitive. This can lead to heart and/or brain damage, or even death.

Anaphylactic shock can cause the following severe allergic reaction symptoms to occur:

  • Swelling of the lips or tongue that indicates throat closure
  • Shortness of breath
  • Low blood pressure
  • A weak or rapid pulse
  • Severe skin rashes
  • Dizziness or fainting
  • Vomiting or diarrhea
  • Painful cramps

If someone is only showing a few of these symptoms, you may be wondering, “How long does it take for a serious allergic reaction to happen?” The stages of an allergic reaction depend on how severely allergic you are to a particular allergen. In most cases, anaphylactic shock can occur within minutes after contact with the allergen has been made.

Regardless of exactly how quickly a reaction occurs, anaphylactic shock can be very serious and life-threatening if not treated quickly. If you or a loved one are experiencing any of the above symptoms, it is in your best interests to seek immediate medical treatment.

How do they treat allergic reactions in the ER?

Once you’re at the ER, a medical professional at Complete Care can see patients within minutes to treat a reaction. Depending on the severity of the reaction, some patients may require additional adrenaline doses or other types of treatment to help restore oxygen or open breathing airways.

In the case of anaphylactic shock, it’s typical for patients who experience these types of reactions to need up to 4 hours of observation by the medical staff. This can ensure that no other reactions (such as biphasic anaphylaxis) will occur.

Our doctor may also prescribe some additional medications to further improve your condition. These may include inhalers, OTC medication, and antihistamines.

Get 24/7 Emergency Care for Allergic Reactions at Complete Care

Now that you’re more aware of when to go to the ER for an allergic reaction, it’s crucial that you act quickly when someone is experiencing severe allergic reaction symptoms. Complete Care’s emergency facilities are fully equipped with a professional medical staff that can aid you with any allergy-related emergency.

Our doctors can provide treatment for everything from a severe allergic reaction to bug bites to severe lactose intolerance symptoms and more. We’re open 24/7, don’t require appointments, and, unlike hospital-based ERs, can typically see patients within minutes. Visit a Complete Care location near you for the award-winning treatment you need during emergencies.