Handedness and allergic response.

Previous reports have linked nonright-handedness with allergies including hay fever, asthma, eczema and urticaria. The present study examined reactions to 20 common allergens (e.g., food, animal fur, dust, drugs, etc.) in a sample of 430 subjects. Individuals who were left-handed or not consistently right-handed showed an elevated frequency of allergic reactions. The criteria used to determine handedness and the existence of allergies are both important factors. The stringent criterion of consistent right-handedness versus nonright-handedness was a more sensitive measure in detecting allergic individuals than was the simple dichotomy of left- versus right-handed. The association with handedness was stronger for individuals with more than one allergy.