Allergies can cause symptoms such as sneezing, itchy eyes, watery eyes, itchy skin, stuffy nose, and headaches among other symptoms. Respiratory and immune system hypersensitivity is the most common cause of allergies. When normal communication from the brain to the spinal cord is interrupted, the body cannot function properly. Many people, who do not normally suffer from allergies, have developed allergies after being involved in an auto accident, suffering from a head injury, or having just moved to a new geographical location. For people who experience regular allergies, interrupted communication between the brain and spine may not be the issue. For them, allergies are usually caused by a delicate immune system that is sensitive to dusts and pollen. However, in some instances an adjustment to upper cervical can provide some relief to allergy symptoms. For others, a subluxation may cause a disruption in nerve communication, which can heighten allergy symptoms.