Sesame seed and sesame seed oil contain masked allergens of growing importance.

Sesame seed and sesame seed oil have been thought of as rare causes of food allergy, representing less than 1% of all food allergy cases. We now report nine cases of IgE-dependent allergy to sesame seed and/or sesame seed oil, six of which were diagnosed in 1995 alone. Our skin test results draw attention to the poor quality of a commercial sesame seed extract and the good sensitivity of skin prick tests made with a freshly prepared sesame seed flour extract. The diagnosis of this food allergy was established by double-blind oral provocation tests, with doses of sesame seed flour ranging from 100 mg to 10 g. Allergy to sesame seed oil was also demonstrated in some cases. The sensitivity of the Pharmacia Phadebas CAP System for the detection of sesame seed-specific IgE was only mediocre. We draw attention to the important use of sesame seed in modern cooking, a fact which may explain the growing frequency of this allergy. We underline the particular risk with sesame seed oil. Sesame seed should also be considered a cause of allergic reactions to drug products and cosmetics.