Anaphylactic shock is by far the greatest potential risk associated with an elimination diet. It is a rare, severe allergic reaction that affects the entire body and often begins immediately after an individual has been exposed to a particular allergen. This kind of reaction can be fatal and requires immediate medical treatment.

Occasionally, a patient who consumes a food allergen suffers an anaphylactic reaction. This can also happen during the reintroduction phase of an elimination diet. Without prompt emergency treatment, anaphylactic shock may interfere with a person’s ability to breathe. An emergency dose of epinephrine (adrenaline) is necessary to reverse these symptoms and potentially to save the patient’s life. For this reason, elimination diets should never be tried except under the strict monitoring of a physician.

Patients who begin an elimination diet are at risk of losing key nutrients. A dietician can help patients choose nonallergenic alternatives that replace nutrients lost as a result of excluding certain foods.