Cashews can make your eyes and inner ears itch if you have an allergy to tree nuts. A tree nut allergy is one of the most common food allergies that can trigger a wide range of symptoms. If you have a tree nut allergy, you may have an allergic reaction to a specific tree nut, such as cashews, or you may be allergic to all tree nuts. Your allergist will determine, through allergy testing, the severity and range of allergies you have to tree nuts.
Cause
Your eyes and inner ears can itch after eating cashews because of increased blood flow, swelling and irritation caused by the chemical, histamine. Histamine helps to protect the body from infection. It is also commonly found in beer, wine, aged cheeses and spinach. If you're allergic to cashews, your body releases high levels of histamine in soft tissues throughout your body. Histamine dilates your blood vessels, increasing blood flow, which, in turn, causes inflammation. Common soft tissues affected by increased histamine include your sinuses, eyes, inner ear, digestive system, skin and lungs.
Effect
When histamine levels increase in the soft tissue in your eyes, you may develop itching eyes, a burning sensation, watery eyes and redness in the white of your eyes. Rubbing the eyes can make the symptoms worse. Your inner ears itch, most likely, from sinus congestion. The sinus cavities can affect various parts of your head when they become inflamed. The swelling can place pressure on your inner ear, leading to minor discomfort and itching.
Testing
Your allergist will perform various testing on your body to determine if the eye and inner ear irritation is the result of an allergic reaction to cashews. Cashew proteins are mixed in with a small amount of fluid that's injected under your skin. If your skin becomes inflamed, red or develops bumps, you may have an allergy. A blood test will confirm if your body creates immunoglobulin E antibodies when cashew proteins are introduced, according to the American Academy of Allergy, Asthma and Immunology.
Treatment
The most effective treatment for a cashew allergy is to avoid consumption of all products that contain the nut. The Food Allergy Initiative states that the federal government requires all packaged foods to contain an allergy warning on the product label if the food contains tree nuts.
