Relationship of allergy to headache.
D000361:Agammaglobulinemia / Q000150:complications; D000485:Allergens; D005512:Food Hypersensitivity / Q000150:complications; D006261:Headache / Q000209:etiology*; D006801:Humans; D006967:Hypersensitivity / Q000150:complications*; D008881:Migraine Disorders / Q000209:etiology; D012216:Rheumatic Diseases / Q000150:complications; D006255:Rhinitis, Allergic, Seasonal / Q000150:complications; D014653:Vascular Headaches / Q000209:etiology
D000485:Allergens