This case report illustrates many of the pitfalls in the general recognition and specific diagnosis of allergic headache. It is of further interest in view of the severity of symptoms and the pronounced degree of food sensitization existing in the absence of skin tests. REPORT OF CASE I. K., a graduate nurse aged 24, developed her initial sick headache at the age of 14, one year after the menarche. Symptoms recurred in 1939 at the age of 17. An allergic investigation at this time revealed a negative past and family history for other evidences of allergic manifestations. Cutaneous tests, including foods, were entirely negative. She was placed on a Rowe No. 1 elimination diet for two periods of ten days each. One headache occurred during this interval. At the time of the diet trials she was subject to a headache every three to four weeks. In May 1940 the attacks