Citric acid is a naturally-occurring acid which is present in all citrus fruits and may be used in other food items as well. Citric acid is also used as a preservative in various other items, including cosmetics and lotions. A citric acid allergy can be mild enough to only cause a mild skin reaction or be severe enough to cause potentially life-threatening complications. A simple blood test is usually all that is necessary to determine the presence of a citric acid allergy. Any questions or concerns about a potential citric acid allergy should be discussed with a doctor or other medical professional.

Skin reactions are among the most common symptoms of a citric acid allergy. These symptoms are usually mild and typically involve a rash which may or may not itch. This rash is usually found around the mouth if the citric acid was ingested internally or on the area of skin which has come into contact with a product containing this ingredient. In some cases, hives may develop or swelling may be noticed, especially in the facial area of the body. Any potential symptoms of a citric acid allergy should be reported to a doctor right away.

Breathing difficulties may arise due to a citric acid allergy. In milder cases, symptoms may include coughing, sneezing, or nasal congestion. Some people may also develop a runny nose or watery eyes. An over the counter antihistamine may help to combat these milder allergic reactions. Severe wheezing or difficulty breathing could indicate a potentially life-threatening medical emergency and should be reported to a medical professional immediately.

Gastrointestinal disturbances may indicate the presence of a citric acid allergy in some cases. Nausea, vomiting, constipation, or diarrhea are some of the most common symptoms. Gas, bloating, or intestinal bleeding are also potential gastrointestinal responses to this type of allergy. In babies with an allergy to citric acid, these symptoms may involve excessive drooling or spitting up.

Physical and emotional changes may sometimes develop in those who have a citric acid allergy. Muscle pain and severe fatigue are possible symptoms which are often overlooked. Mood changes such as irritability, a feeling of anxiety, or unexplained bouts of crying are sometimes experienced as part of an allergic reaction. For milder symptoms, eliminating citric acid from the diet may be all that is needed. More severe symptoms require immediate medical attention in order to avoid potentially fatal complications.