A walnut allergy is a type of tree nut allergy. People who develop an allergic reaction to walnuts may or may not be allergic to other tree nuts. Like other types of food allergies, it is also caused by a hypersensitive immune system. People usually develop an allergy to walnuts in their childhood. However, it is also possible to develop this allergy at some later stages of life. Causes and Risk Factors As has been mentioned already, both environmental and food allergies are associated with a hypersensitive immune system. In the case of a food allergy, the immune system mistakenly recognizes the particular food or a substance present in it as a foreign invading particle, and hence triggers the production of antibodies and chemicals like histamine to destroy it. Histamine is mainly responsible for producing the characteristic signs and symptoms of an allergic reaction. Tree nut allergy is caused when the immune system produces an allergic reaction in response to a protein found in tree nuts. A family history of allergies, including food allergy is the most important risk factor for developing an allergy to walnuts. Signs and Symptoms Both adults and children can develop an allergy to walnuts. However, it is more common in children. The symptoms of the allergic reaction can be mild or serious. In general, one can observe the following signs and symptoms that can develop immediately or within a few hours after consuming walnuts.

• Itching and hives
• Unusual swelling of the mouth, tongue, or the lips
• Watery eyes
• A runny nose and sneezing
• Coughing
• Nasal congestion
• Shortness of breath
• Wheezing
• Abdominal cramping
• Nausea and vomiting
• Indigestion and diarrhea
• Rapid pulse
• Dizziness or lightheadedness
• Loss of consciousness

Out of these, shortness of breath, swelling of the throat, tongue, lips, and the mouth, dizziness, and loss of consciousness are the serious symptoms. These symptoms can be caused by a severe allergic reaction to walnuts, which is called anaphylaxis. Anaphylaxis is a life-threatening condition, which can lead to shock. Apart from these, individuals suffering from asthma can experience asthma attacks due to an allergic reaction to walnuts. Diagnosis and Treatment This food allergy is usually diagnosed with the help of a blood test and skin prick test. The best way to prevent this allergy is to avoid walnuts, and any food or product that contains them. As far as the treatment is concerned, antihistamines can be used if the allergic reaction produces symptoms like itching, hives, and allergic rhinitis. However, antihistamines cannot relieve the symptoms of asthma. For treating asthma, physicians usually recommend bronchodilators. For a severe allergic reaction or anaphylaxis, adrenaline injections are used. It is possible to prevent and manage this allergy by avoiding any food or product that contains walnuts. Many times, people having walnut allergy can also develop an allergic reaction to other types of tree nuts, like almonds, cashews, and pecans. The signs and symptoms of this allergy can be mild at times, but they should never be neglected. Even the mild symptoms of an allergic reaction should be properly evaluated with the help of a physician, in order to prevent serious complications. Disclaimer: This Buzzle article is for informative purposes only, and should not be replaced for the advice of a medical professional.