Tree Nut Allergy
When you think of allergies, you might picture lots of sneezing and runny noses. But unlike an allergy to spring flowers, a tree nut allergy can cause trouble breathing and other very serious health problems. That's why it's very important for someone with a nut allergy to avoid eating tree nuts, which can be tough because they're in lots of foods. These are nuts that grow on trees, such as almonds, walnuts, pecans, cashews, hazelnuts, Brazil nuts, and pistachios.
What Happens With a Tree Nut Allergy?
Your immune system normally fights infections. But when someone has a tree nut allergy, it overreacts to proteins in the nut. If the person eats something that contains the nut, the body thinks these proteins are harmful invaders and responds by working very hard to fight off the invader. This causes an allergic reaction.
What Are the Signs & Symptoms of a Tree Nut Allergy?
When someone with a tree nut allergy has something with nuts in it, the body releases chemicals like histamine (pronounced: HISS-tuh-meen).
This can cause symptoms such as:
- wheezing
- trouble breathing
- coughing
- sneezing
- hoarseness
- throat tightness
- stomachache
- vomiting
- diarrhea
- itchy, watery, or swollen eyes
- hives
- swelling
- a drop in blood pressure
- dizziness or fainting
- anxiety or a feeling something bad is happening
Reactions to foods, like tree nuts, can vary. Sometimes the same person can react differently at different times.
In the most serious cases, a tree nut allergy can cause anaphylaxis (say: an-uh-fuh-LAK-sis). Anaphylaxis is a sudden, life-threatening allergic reaction. A person's blood pressure can drop, it can be harder to breathe, and the tongue can swell. People at risk for this kind of a reaction have to be very careful and need a plan for handling emergencies, when they might need to get special medicine to stop these symptoms from getting worse.
What Will the Doctor Do?
If your doctor thinks you might have a tree nut allergy, they will probably send you to see a doctor who specializes in allergies. The allergist (allergy specialist) will ask you about past reactions and what symptoms you have had.
The allergist may also ask whether anyone else in your family has allergies or other allergy conditions, such as eczema or asthma. Researchers aren't sure why some people have food allergies and others don't, but they sometimes run in families.
The allergist may also want to do a skin test. This is a way of seeing how your body reacts to a very small amount of the nut that is giving you trouble. The allergist will use a liquid extract of the nut that seems to be causing you symptoms. During skin testing, a little scratch on your skin is made (it will be just a quick pinch). That's how just a little of the liquid nut gets into your skin. If you get a reddish, itchy, raised spot, it shows that you may be allergic to that food or substance.
Skin tests are the best test for food allergies, but if more information is needed, the doctor may also order a blood test.
Sometimes, the doctor tests for food allergies by carefully exposing you to a very small amount of the food. But do not try this at home! The only place for an allergy test is at the allergist's office, where they are specially trained and could give you medicine right away if you had a reaction.
How Is an Allergic Reaction Treated?
The best way to not have an allergic reaction is to avoid the nut. That means not eating that nut, and also avoiding the nut when it's mixed in foods. (Sometimes these foods don't even taste nutty! Would you believe chili sometimes contains nuts?)
Staying safe means reading food labels and paying attention to what they say about how the food was made. Some foods don't contain peanuts, but are made in factories that make other items that do contain them. The problem is that the equipment can be used for both foods, causing "cross-contamination." That's the same thing that happens in your own house if someone spreads peanut butter on a sandwich and dips that same knife into the jar of jelly.
After checking the ingredients list, look on the label for phrases like "may contain tree nuts" or "produced on shared equipment with tree nuts or peanuts." People who are allergic to tree nuts should avoid foods that have these statements on the label.
Some of the highest-risk foods for people with a tree nut allergy are cookies and baked goods, candy, ice cream, and sauces.
Talk to your allergist about how to stay safe in the school cafeteria or when eating at restaurants.
Have an Emergency Plan
If you have a nut allergy, your allergist will help you and a parent create a plan for how to handle a reaction, just in case. That way your teachers, the school nurse, your basketball coach, your friends — everyone will know what a reaction looks like and how to respond.
To treat anaphylaxis right away, doctors recommend that people with a nut allergy keep 2 doses of epinephrine (say: eh-puh-NEH-frin) with them. Epinephrine comes in an easy-to-carry container. You and your parent can work out whether you carry this or someone at school keeps it on hand for you. You'll also need to identify a person who will give you the medicine.
You might want to have antihistamine medicine with you too for mild reactions. But if anaphylaxis is happening, this medicine is never a substitute for epinephrine.
After getting epinephrine, you must go to the hospital or other medical facility, where they will keep an eye on you for at least 4 hours and make sure the reaction is under control and does not come back.
What Else Should I Know?
If you find out you have a nut allergy, don't be shy about it. It's important to tell your friends, family, coaches, and teachers at school. The more people who know, the better off you are because they can help you stay away from the nut that causes you problems.
Telling the server in a restaurant is also very important because they can help you avoid dishes that contain nuts. Likewise, a coach or teacher would be able to choose snacks for the group that don't contain nuts.
It's great to have people like your parents, who can help you avoid nuts, but you'll also want to start learning how to avoid them on your own.