Q. Why do I sneeze when I feel cold?

A. The explosive release of air through the nose and mouth that is a sneeze is a neurological process that usually starts with physical stimulation of the wide-ranging trigeminal nerve. This nerve’s branches are responsible for sensation in the face and surrounding skull areas.

The branches that terminate in the facial skin are sensitive to chemical, mechanical and tactile stimulation, including sensations of pain and temperature. Branches also serve the sensitive lining of the nasal passages.

While irritation of the nasal passages is the most common trigger for a sneeze, the presence of cold, dust-bearing air is not necessary. Simply being cold and shivering, or even moving from one temperature zone to another, can jar the nerve.