A wheat allergy is usually a short-lived, but important allergy of childhood. Around 0.4% of children in the USA have a wheat allergy. Almost all children with a wheat allergy can tolerate wheat by adolescence.
More common symptoms are skin reactions such as dermatitis and urticaria (hives) but swelling of the airways and anaphylaxis can occur.
In adults the most common reaction is as a triggered condition known as food dependent, exercise induced anaplylaxis (FDEIA)
Source: Manual of Dietetic Practice, 5th Edition, 2014
Additional Information: Medscape