According to Food Allergy Research & Education, approximately 4 percent of adults in the United States have a food allergy. Although banana allergies are not among the most common types of fruit allergy, they can cause life-threatening symptoms. See your doctor if you suspect you are allergic to bananas.

Banana Intolerance

While true allergic reactions to the banana fruit are rare, your body may not be able to break down a certain chemical in the fruit. Known as amines, these chemicals require your body to produce an enzyme called diamine oxidase. If your body is unable to produce adequate amounts of this enzyme, you may experience allergy-like reactions. Otherwise known as banana intolerance, these reactions may involve stomach cramps, heart palpitations, headaches, vomiting, diarrhea, nausea, coughing, sneezing, breathing problems, watery eyes and a runny nose.

Banana Allergy

While your allergy-like symptoms may be due to banana intolerance, a true banana allergy arises from your body's inability to break down a protein called chitinase. Also present in kiwis and avocados, this protein may cause a type 1 allergic reaction. This type of reaction is typically severe and nearly instantaneous, with symptoms setting in within minutes of touching or eating the fruit. As reactions vary between minor discomfort and death, your symptoms may or may not include itchy skin, rashes, eye problems, difficulty breathing, runny nose, a variety of stomach issues and a life-threatening allergic reaction called anaphylaxis.

Birch Allergy

As true banana allergies are rare, your allergic reaction to bananas may arise from a broader allergy to birch trees and pollen. These allergies typically cause a symptom combination known as oral allergy syndrome within a few minutes of eating. Common among hay fever sufferers, oral allergy syndrome may lead to tingling, itching and swelling on your lips and in your mouth and throat. As these allergies arise from contact with fresh fruit, cooking or briefly heating up your bananas may prevent this reaction.

Latex-Fruit Syndrome

Bananas contain a protein and potential allergen similar to that found in natural rubber latex. If you experience allergic reactions to surgical gloves, condoms and balloons, for example, your allergy may be due to a condition called the latex-fruit syndrome. This condition can result in itching and hives all over your body, stomach pains, breathing difficulties, vomiting and anaphylaxis. As this potentially life-threatening reaction can occur soon after eating a banana, you should consult immediate medical help if you experience any signs of a severe allergic reaction.