What To Do for an Allergic Reaction

How to handle breathing difficulties, rashes, hives and more
Person with rash surrounded by circles featuring small illustrations of food, pets, and plants

Pollen, dust, animal dander, nuts, shellfish and other foods — these can all cause an allergic reaction in susceptible people.

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Symptoms can range from being mildly uncomfortable and annoying to serious and life-threatening. So, it’s good to know what to do if you or someone you’re with has an allergic reaction.

Allergist and immunologist Anuja Kapil, MD, breaks down what to look for in an allergic reaction and how to handle different situations.

Symptoms of an allergic reaction

When you eat, breathe in or touch something that you’re allergic to, your immune system produces histamines to deal with the bothersome substance.

But while your body’s intentions might be good, that natural response can trigger symptoms like:

  • Itching.
  • A rash.
  • Hives (large, pink bumps or swollen areas).
  • Sneezing and watery eyes.
  • Swelling in the mouth or throat.
  • Rapid or difficult breathing.

Treatment options for allergic reactions

Given the range of reactions to allergens, treatment recommendations can vary from immediately calling 911 for help to simple at-home remedies. Different situations require vastly different responses.

So, let’s break it down by some of the more common symptoms.

Difficulty breathing or throat swelling

Don’t delay getting medical attention for anaphylaxis, which is when allergic reactions take a severe turn. Dial 911 — and do it ASAP.

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“Calling 911 is better than driving to the emergency department,” says Dr. Kapil. “Emergency medical technicians in an ambulance have protocols and access to treatments specifically for severe allergic reactions.”

In addition, many people with potentially life-threatening allergies carry an injector that can deliver a dose of epinephrine (adrenaline). This shot of adrenaline — typically delivered in your thigh — can help reverse severe allergic reactions while you await medical care.

Use the epinephrine injector if a reaction is serious. Your or someone’s life may depend on taking quick action.

Food allergies are the most common trigger of anaphylaxis. Severe reactions also can be brought on insect stings, latex or medications.

An allergic reaction that makes it difficult to breathe can create a sense of impending doom, says Dr. Kapil. Understand that an anaphylactic reaction can be an intense situation. It’s important to remain calm.

Skin reactions (itching, redness or a rash)

Wash the affected skin area with mild soap and lukewarm water to remove the allergen. Afterward, apply hydrocortisone cream or lotion. Calamine lotion and cool compresses may also bring relief.

If your itchiness is severe, your rash doesn’t go away or you see signs of infection, call your doctor.

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A few other tips:

  • If you think you know what’s causing your skin reaction — makeup or jewelry, for instance — stop using the product or wearing the item.
  • If the reaction is due to an external source such as poison ivy, poison sumac or poison oak, make sure to wash clothing or other items that may have the irritant on them.


The good news? Hives will subside in time. Meanwhile, it helps to:

  • Apply cool compresses.
  • Avoid hot showers and bathwater.
  • Wear loose clothing to avoid irritating your skin.
  • Sleep in a cool room.

Itching, sneezing and watery eyes

When you have multiple allergic symptoms, a nasal spray or over-the-counter antihistamine such as loratadine (Claritin®) can treat them.

Dr. Kapil advises against using products that have a sedative effect, such as Benadryl®.

Don’t be afraid to seek help

Knowing what causes your allergic reaction can help you avoid future situations. It could even connect the dots to other potential allergens, too. For example:

  • If you’re allergic to latex, it’s possible you’ll also react to avocados, kiwifruit and other tropical fruit.
  • If you’re allergic to birch pollen, it’s possible you’ll also react to apples or peaches.

So follow up with your doctor and ask about allergy testing, advises Dr. Kapil. “Testing can help pinpoint the reason behind your reaction,” he says. “Better yet, it might help keep you away from what triggered it.”

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