Strawberry allergy. Conceptual image of a woman holding a glass sphere containing strawberries (Fragaria sp.). This could represent 'strawberry allergy'. Strawberries are a fairly common cause of food allergy, particularly among adults. A true food allergy causes an immune response resulting in a rash, itching, swelling and, more severely, breathing difficulties or collapse. Alternatively, the allergy may be more localised, causing redness and itching around the mouth and throat. A delayed allergic reaction to foods can cause diarrhoea, bloating and anaemia, which result in malnutrition. The best form of treatment of food allergy is by identifying and avoiding the cause.