Chocolate allergy symptoms include abdominal upset, stuffy nose, watery eyes, migraines, hives and lightheadedness, according to HowStuffWorks. Symptoms can also manifest as swelling in the mouth, vomiting, diarrhea, sneezing, coughing and fainting. In severe cases, a chocolate allergy can result in life-threatening symptoms, such as difficulty breathing, reduced blood pressure, cardiovascular complications and anaphylaxis.
HowStuffWorks recommends visiting a doctor to be sure that any symptoms related to chocolate consumption are signs of a true food allergy and not a simple food intolerance. There are differences between the two; a food intolerance causes symptoms localized to the gastrointestinal tract, and a food allergy can be potentially dangerous. An allergist is able to perform tests to determine the exact foods or ingredients that are creating allergic reactions in a patient. Most often, people are not affected by chocolate specifically but by an ingredient within the chocolate, such as nuts, eggs, wheat or milk. The Cleveland Clinic explains that the body of an allergic person sees the proteins present within these ingredients as dangerous invaders and reacts to them by releasing histamines to rid the body of the substances. The location of the histamine release coincides with the area in which the symptoms manifest. For example, if histamines are released in the skin, a person's allergic reaction manifests as hives, itching and swelling.