A peanut allergy is when a person's immune (infection-fighting) system responds as if peanuts are harmful to the body. Most often, allergic reactions happen from eating peanut or food that contains peanut. Less often, allergic reactions happen when an allergic person breathes in tiny pieces or dust, like from a package of peanuts. Touching peanut can also cause a skin reaction.
Common symptoms include:
The above symptoms usually show up quickly, minutes to hours after eating peanut. A severe allergic reaction is also called "anaphylaxis." When a person has anaphylaxis, they can get very sick, very quickly.
Although uncommon, a peanut allergy also sometimes triggers other symptoms. When this happens, it is usually hours to days after eating peanut. These symptoms include:
Yes. Your doctor or nurse will ask about the foods you eat and the symptoms you have. They will also do a test to check for a peanut allergy. Tests can include:
One blood test looks for IgE to whole peanut. Another test, called "component testing," looks for IgE to several different proteins found in peanuts. These test results can give your doctor more information about your allergy and how best to manage it.
Some people have a test called a "food challenge." This involves gradually eating a serving of peanuts and seeing whether it causes symptoms. For safety reasons, this test is done only in a doctor's office or hospital. Usually, a food challenge is only done if other tests are not clear, or if a doctor wants to check if a person's allergy has gone away.
As of now, there is no definite cure for a peanut allergy. A treatment called "oral immunotherapy" might lower the risk of an allergic reaction if a person is accidentally exposed to peanut. Oral immunotherapy involves giving a child tiny amounts of peanut in a controlled way. The treatment is started in a clinic or hospital, where the child can be monitored and treated if they have a reaction. Then, they continue to take daily doses at home. The goal is to increase the dose of peanut very slowly over time, so the immune system doesn't react to it. Each dose increase is done in the clinic or hospital.
This type of treatment comes with risks and is not likely to make a person's allergy go away completely. But it might be an option in certain situations. If you are interested in learning more about oral immunotherapy, talk with your child's doctor or nurse.
Severe allergic reactions to peanuts are usually treated with medicine called epinephrine. Epinephrine comes in a device called an "auto-injector." This device gives you a shot of epinephrine (picture 3). When your doctor prescribes an auto-injector, they will show you how to use it and give you instructions for when to use it. Keep your auto-injector with you at all times. Most doctors recommend carrying 2 auto-injectors in case you need a second dose.
After you use an auto-injector, call for an ambulance (in the US and Canada, dial 9-1-1). Epinephrine doesn't last very long in the body, and symptoms can sometimes come back as it wears off. In the hospital, doctors can watch you and give you more medicine if needed.
If you think someone is having a severe allergic reaction and you do not have an epinephrine auto-injector, call for emergency medical help right away.
The only way to prevent an allergic reaction is to completely avoid eating peanuts or foods with peanuts in them. To know whether a food contains peanuts, you will need to read its ingredient label. Some countries (including the United States) have laws that make companies clearly list whether a food has peanuts in it.
Some foods have warning labels for food allergies, such as "May contain peanuts." These foods might have been made on machines or in factories that also made other foods with peanuts. Doctors usually recommend that people with a peanut allergy avoid these foods.
Foods that are especially likely to contain peanuts include baked goods and Asian, African, and Mexican foods. If you eat at a restaurant, bakery, or ice cream parlor, be sure to tell your server about your peanut allergy.
People with a peanut allergy:
If your child has a peanut allergy, let his or her caregivers, schools, and camps know. You should:
Most children do not outgrow their peanut allergy, but some do. Your child's doctor will monitor your child's peanut allergy over time to see whether they outgrow it.
Hives are raised, red patches of skin that are usually very itchy. They usually come and go within a few hours, but they can show up again and again in some people.
This photo shows how to use an epinephrine autoinjector. When using an autoinjector, hold it in your fist, with your fingers away from either end. Press it firmly into your outer thigh and hold it in place for at least a few seconds. (Check the directions that come with your autoinjector so you know how long to hold it.)
It is best to sit down and if you feel dizzy, to lie down. If you pass out, another person should lower you to the ground and raise your legs up to help blood flow to your heart and brain.
You can get more information about peanut allergies (and other food allergies) from an organization called Food Allergy Research & Education. Their website is www.foodallergy.org.
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