[clarification needed] At present, many of the allergens of wheat have not been characterized; however, the early studies found many to be in the albumin class.

[9] A recent study in Europe confirmed the increased presence of allergies to amylase/trypsin inhibitors (serpins)[5][10] and lipid transfer protein (LPT),[11] but less reactivity to the globulin fraction.

[12] The allergies tend to differ between populations (Italian, Japanese, Danish or Swiss),[citation needed] indicating a potential genetic component to these reactivities.

The peptides are often 1 kD in size (9 amino acid residues in length) and may increase the allergic response.

[citation needed] Common symptoms of a wheat allergy include eczema (atopic dermatitis), hives (urticaria), asthma, "hay fever" (allergic rhinitis), angioedema (tissue swelling due to fluid leakage from blood vessels), abdominal cramps, nausea, and vomiting.

[20] Rarer symptoms include [citation needed] anaphylactic shock, anxiety, arthritis, bloated stomach, chest pains, depression or mood swings, diarrhea, dizziness, headache, joint and muscle aches and pains (may be associated with progressive arthritis), palpitations, psoriasis, irritable bowel syndrome (IBS), swollen throat or tongue, tiredness and lethargy, and unexplained cough.

[citation needed] Wheat gliadins and potentially oat avenins are associated with another disease, known as wheat-dependent exercise induced anaphylaxis (WDEIA) which is similar to baker's allergy as both are mediated by IgE responses.

[1] In WDEIA, however, the ω-gliadins or a high molecular weight glutenin subunit, and similar proteins in other Triticeae genera, enter the blood stream during exercise where they cause acute asthmatic or allergic reaction.

[1] Wheat may specifically induce WDEIA and certain chronic urticaria because the anti-gliadin IgE detects ω5-gliadins expressed by most of the Gli-B1 alleles, but prolamins extracted from rye or wheat/rye translocates invoke almost no responses.

This indicates that nascent mutations on the B genome of wheat are from a small number of cultivated Triticeae species.

[22] In addition, a gluten-extrinsic allergen has been identified as aspergillus amylase, added to flour to increase its baking properties.

[citation needed] Contact sensitivity,[23] atopic dermatitis,[24] eczema, and urticaria appear to be related phenomena, the cause of which is generally believed to be the hydrophobic prolamin components of certain Triticeae, Aveneae cultivars.

[26] Studies of the wheat-dependent exercise induced anaphylaxis demonstrate that atopy and EIA can be triggered from the ingestion wheat proteins into the blood, where IgE reacts within allergens in the dermal tissues.

Some individuals may be so sensitive that low dose aspirin therapy can increase risk for both atopy and WDEIA.

In a recent study in Turkey, 8 of 20 RA patients had wheat reactivities on the radioallergosorbent test (RAST).

In addition, cross-reactive anti-beef-collagen antibodies (IgG) may explain some rheumatoid arthritis (RA) incidents.

[33] Other studies show that digestion of wheat proteins to about 10 amino acids can increase the allergic response 10-fold.

[citation needed] Triticeae gluten-free oats (free of wheat, rye or barley) may be a useful source of cereal fiber.

Treatment for accidental ingestion of wheat products by allergic individuals varies depending on the sensitivity of the person.