Psychiatrist Bennett Braun, author of The Treatment of Multiple Personality Disorder, describes the case of Timmy, who also had multiple personalities. One personality was allergic to orange juice, and when this personality drank orange juice, Timmy would break into blistering hives. However, another personality was able to drink orange juice uneventfully. If the allergic personality was in the midst of an allergy attack and he shifted back to the non-allergic personality, the hives would disappear instantly.