First Aid: Allergic Reactions

First Aid: Allergic Reactions

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First Aid: Allergic Reactions

Limited reaction

A limited (localized) reaction affects only the area of contact. Some reactions may not show up for days. Others can occur almost immediately.

Step 1

Stop the source

  • If the person has been stung, scrape the stinger away with the edge of a credit card 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 specific 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 and wash in hot water all clothing that may have plant oils (or any other substance that has caused a reaction) on them. Shower with plenty of soap to wash remaining plant oils (or other allergens) off the skin.

  • Control itching by making a thick paste of baking soda and water. Apply the paste directly to the skin.

Severe reaction

A severe (systemic) reaction affects the entire body. In extreme cases, the airways from mouth to lungs may swell (anaphylaxis). The reaction may happen right away or over several hours.

Step 1

Calm the person

  • Help the person into a comfortable position. Prop up his or her head to aid breathing.

  • Tell the person to remain still and limit talking.

  • If the person carries medicine (epinephrine) to control anaphylaxis, help him or her use it.

  • Prevent any further contact with or exposure to allergen. 

Step 2

Monitor breathing

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

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

Call 911 immediately if the person has any of the following:

  • Trouble breathing

  • A history of airway swelling (anaphylaxis)

While you wait for help:

  • Reassure the person.

  • Treat for shock or provide rescue breathing or CPR, if needed.

An allergic reaction may become more serious over time. Seek medical help if any of the following is true:

  • A rash or hives covers the face, genitals, or most of the body.

  • An entire body part, such as an arm or leg, swells.

  • The tongue or lips begin to swell.