Symptoms

First Aid: Allergic Reactions

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Limited reaction

A limited reaction affects only the area of contact. Some reactions may not show up for days. Others can occur almost right away.

Step 1. Stop the source

  • If the person has been stung, calmly move away to prevent more stings. Scrape the stinger away with the edge of a credit card, your fingernail, or the dull edge of a knife. Don’t use fingers or tweezers to remove a stinger. If pinched, the stinger may empty its venom into the skin.

  • If the reaction is caused by eating a food or taking a medicine, the person should not eat or take the substance again.

Step 2. Treat skin irritation

  • Wash insect bites with soap and water.

  • Remove all clothing that may have plant oils. Or any other substance that has caused a reaction. Wash the clothes in hot water. Shower with plenty of soap to wash allergens off the skin.

  • Ask your healthcare provider how to control itchy or irritated skin.


Severe reaction

Anaphylaxis is a severe life-threatening allergic reaction. It needs medical attention right away. In extreme cases, the airways may swell and cause difficulty breathing. The reaction may happen right away or over several hours. Give epinephrine if it's available. Call 911 right away for medical help. Call even if the medicine seems to be helping.

Step 1. Calm the person

  • Help the person lie down with their legs raised. Don't do this if they're vomiting or having trouble breathing. But help them into a comfortable position with their legs raised if possible. Pregnant people should be on their left side.

  • Tell the person to remain still and limit talking. Reassure them that help is on the way.

Step 2. Give epinephrine if available

  • If the person carries an epinephrine auto-injector or epinephrine nasal spray, help them use it.

  • Prevent any further contact with or exposure to allergen.

Step 3. Monitor breathing

  • Watch for signs of airway swelling. For example, wheezing or swollen lips. With an extreme reaction, the person may have trouble getting any breath.

  • Do rescue breathing, if needed. In extreme cases, you may not be able to get air into the lungs.


Call 911

Call 911 right away if the person has any of the following:

  • Trouble breathing, shortness of breath, wheezing, or continued cough

  • A history of airway swelling (anaphylaxis)

  • Continued vomiting

  • Belly pain

  • Severe diarrhea

  • Lips, skin, or nail beds look pale, blue, purple, or gray

  • Feeling faint, dizzy, or confused

  • Weak pulse

  • Throat feels tight or hoarse

  • Trouble swallowing or talking

  • Swelling of the tongue or lips

  • Feeling of doom or feeling something bad is about to happen

  • Hives all over the body or redness

  • Loss of consciousness

© 2000-2026 The StayWell Company, LLC. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.

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