Topics in Allergy
Tree Nut Allergy
Tree nuts (nuts other than peanuts) are a common food causing IgE allergic reactions (see Food Allergy handout). IgE types of food allergies cause immediate and potentially very severe life threatening reactions when even small amounts of the food are ingested. Managing this type of reaction requires awareness of sources of nuts, having adrenalin (usually in the form of an EpiPen) available, and use of Medic Alert bracelets.
Tree nuts are true nuts, not related to peanut which is a legume. The allergic protein is also found in small amounts in nut oils of tree nuts. Many nuts do not cross react allergically (i.e. a person usually reacts to one nut but not necessarily other nuts). Some nuts such as cashew and pistachio do cross react and someone who is allergic to cashew will very likely react to pistachio. Others, such as coconut and walnut, rarely cross react with other nuts. We do not know about all cross reactions between nuts and people who are allergic to one nut should avoid all nuts because of this.
We would also recommend avoiding peanuts even though they are unrelated to tree nuts. If you are allergic to tree nuts, your immune system can become allergic to other foods and it is extremely easy to become allergic to peanuts.
The most common sources of nuts in foods are candies and cookies. We recommend only eating commercial candies and cookies, avoiding homemade sources. Read labels carefully and form a list of candies and cookies that you know are safe. Only eat candies and cookies from your "safe" list. Use extreme caution when trying a new product. Be cautious with restaurants where nuts are added to some dishes. Make sure the dishes and pans have been washed with soap and water before your meal is prepared in them. If one person in a home is allergic to nuts it is best to keep all nut products out of the home. The FOOD ALLERGY NETWORK has additional and frequently updated information about sources of nuts in commercial foods.
Food Allergy Network
10400 Eaton Place, Suite 107
Fairfax, VA 22030-3179
703.691.3179 Fax 703.691.2713
You should carry an EpiPen and know how to use it. Caregivers also need to be instructed. Children can carry an EpiPen at school with a note from our office. EpiPens may be given through clothing. If the EpiPen is used, you need to be seen and observed in an emergency room. Reactions have recurred even 2-3 hours after the initial reaction seemed to be improving.
If you have an anaphylactic reaction to nuts, spit the food out of your mouth, rinse and spit with water or other liquid, and use the EpiPen. USE THE EPIPEN AT THE EARLIEST SIGN OF A REACTION. You should also consider going to an emergency room unless the reaction was very mild. Even then there is a risk it could recur. Do not go to a restroom or other private place to use the EpiPen. Notify someone you are having an allergic reaction, tell them you are giving yourself a shot, and ask them to call 911. Wearing your Medic Alert bracelet is important and lets emergency personnel know what is happening if you are unable to communicate with them.
Patients at risk of anaphylaxis to foods or other materials should avoid beta blocker medications (used for heart, blood pressure, and glaucoma problems) as these will block the effect of the EpiPen.
With these precautions of avoidance, Medic Alert bracelet and availability of EpiPen nut allergy is a manageable problem. Although there have been rare exceptions fatal reactions almost never occur when an EpiPen is available and used early in the event of a reaction. New treatments for nut and similar food allergies may be available within the next few years.