How do I know if I have an allergy to ascorbic acid?

Allergy symptoms. Allergy symptoms are varied and may include hives, itchy, swelling, runny nose, sneezing, coughing, wheezing, throat swelling, shortness of breath, stomach pain, vomiting or diarrhea. When people are allergic to a food most reactions occur soon after ingestion. It is doubtful that someone is allergic to ascorbic acid although it is possible to react to citrus fruits. .